Tex-600-J, Sampling and Testing Hydrated Lime, Quicklime ... · Tex-600-J, Sampling and Testing...

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Texas Department of Transportation 1 01/01 – 01/06 Tex-600-J, Sampling and Testing Hydrated Lime, Quicklime, and Commercial Lime Slurry Contents: Section 1 — Overview..............................................................................................................2 Section 2 — Part I, Sampling Lime Products ...........................................................................3 Section 3 — Part II, Testing Hydrated Lime ............................................................................9 Section 4 — Part III, Testing Commercial Lime Slurry.........................................................23 Section 5 — Part IV, Testing Type C Quicklime ...................................................................28 Section 6 — Archived Versions .............................................................................................32

Transcript of Tex-600-J, Sampling and Testing Hydrated Lime, Quicklime ... · Tex-600-J, Sampling and Testing...

Page 1: Tex-600-J, Sampling and Testing Hydrated Lime, Quicklime ... · Tex-600-J, Sampling and Testing Hydrated Lime, Quicklime, and Commercial Lime Slurry Section 1 — Overview Texas Department

Texas Department of Transportation 1 01/01 – 01/06

Tex-600-J, Sampling and Testing Hydrated Lime, Quicklime, and Commercial Lime Slurry

Contents: Section 1 — Overview..............................................................................................................2

Section 2 — Part I, Sampling Lime Products...........................................................................3

Section 3 — Part II, Testing Hydrated Lime............................................................................9

Section 4 — Part III, Testing Commercial Lime Slurry.........................................................23

Section 5 — Part IV, Testing Type C Quicklime...................................................................28

Section 6 — Archived Versions .............................................................................................32

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Section 1 Overview

Effective Date: January 2001 – January 2006.

This method, divided into four parts, describes the sampling and testing of hydrated lime, quicklime, and commercial lime slurry.

Units of Measurement

The values given in parentheses (if provided) are not standard and may not be exact mathematical conversions. Use each system of units separately. Combining values from the two systems may result in nonconformance with the standard.

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Section 2 Part I, Sampling Lime Products

This part covers the sampling of lime in powdered form as:

♦ Bulk Hydrate, discharged from tank trucks.

♦ Hydrated Lime, as bagged hydrate from bag trucks being loaded, or from bagged shipments after delivery to warehouse or job site.

♦ Quicklime in crushed or pebble form, discharged from tank trucks.

♦ Commercial Lime Slurry, a mixture of hydrated lime solids in water, from sampling port at the plant site or in the distributor truck.

Apparatus

The following apparatus is required:

Bulk Hydrate

♦ paint brush, 51 mm (2 in.) wide

♦ 4 L (1 gal.) bucket with double friction type lid and bail

♦ top hatch sampling device consisting of a 2.8 m (9 ft.) length of 38 mm (1.5 in.) IPS PVC 1120 plastic pipe of SDR 1.10 MPa (26,160 psi), to meet ASTM D 2241-94, "Specification for Poly (Vinyl Chloride) (PVC) Pressure-Rated Pipe (SDR Series)." • This pipe is fitted at one end with a rubber stopper drilled with a 6.4 mm (0.25 in.)

diameter hole. • The stopper may be cemented in place, using a standard adhesive epoxy. • A 76 mm x 51 mm (3 in. x 2 in.) half-round plate of 12-gauge steel, to which a

hook is spot-welded, should be riveted and cemented with epoxy to the rubber stopper end of the pipe.

• The 76 mm (3 in.) long metal hook should be 13 mm x 19 mm (0.5 in. x 0.75 in.), doubled over section, with a 6.4 mm (0.25 in.) slot.

• The opening of the hook should face away from the rubber stopper. • The hook will catch the bucket bail, so the bucket and pipe can be lowered to the

ground. This allows the sampler to alight from the truck safely.

♦ bottom sampling tube consisting of two concentric plastic pipes: • The outer pipe is a 3.2 m (126 in.) long, 38 mm (1.5 in.) inside diameter IPS PVC

plastic pipe fitted at one end with a tip made from a 191 mm (7.5 in.) length of solid aluminum round stock 41 mm (1 5/8 in.) in diameter tapered to a point along 165 mm (6.5 in.) of its length, inserted 25 mm (1 in.) into the tube and fastened with two screws through the wall of the pipe into tapped holes on either side of the tip.

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• The point of the tip should be rounded to a 13 mm (0.5 in.) diameter point for safety.

• An adhesive epoxy may be used to mold an epoxy tip in a metal, foil or cardboard mold.

• The inner pipe is a 32 mm (1.25 in.) IPS PVC plastic pipe 3.0 m (10 ft.) long. • Slip this pipe inside the outer pipe. It will extend beyond the outer pipe at the upper

end, forming a handle to allow the sampler to rotate the inner tube within the outer tube.

• Cut a 32 mm (1.25 in.) wide by 305 mm (12 in.) long sampling port through both pipes 38 mm (1.5 in.) from the lower, plugged, end.

• Create index marks on the outside of the outer and inner pipes at the upper end labeled "open" and "closed," to indicate the relative position of the opening in the inner pipe to that of the outer.

Bagged Lime

♦ paint brush, 51 mm (2 in.) wide

♦ 4 L (1 gal.) bucket with double friction type lid and bail

♦ bag sampling tube made from 19 mm (0.75 in.) diameter steel electrical conduit 1 m (3 ft.) long. The opening at one end shall be tapered with a 102 mm (4 in.) diagonal cut.

Quicklime

♦ safety goggles

♦ respirator

♦ rubber gloves

♦ paint brush, 51 mm (2 in.) wide

♦ 4 L (1 gal.) bucket with double friction type lid and bail

♦ device designed to hold a sample bucket between the wheel path of a bulk transport discharging quicklime without allowing the bucket to turn over, but permitting safe, easy removal of the container from the windrow with the sample intact. One suggested design: • From 19 mm (0.75 in.) plywood, cut three pieces, one 457 mm (18 in.) square,

another 356 mm (14 in.) square and the third 254 mm (10 in.) square. • Cut holes to closely fit the 4 L (1 gal.) sample bucket in the centers of the smaller

two plywood squares. • Center the 254 mm (10 in.) board on the 356 mm (14 in.) board and fasten them

together. • Center these two on top of the 457 mm (18 in.) board and fastened together. • To a corner of this unit fasten a 2.4 m (8 ft.) length of 3.2 mm (1/8 in.) diameter

flexible steel cable.

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• To the other end of the cable attach a 254 mm (10 in.) length of steel conduit or wooden dowel as a "T" handle, used to slide the filled bucket from wind-rowed quicklime.

♦ plastic sample bag 457 mm x 241 mm (18 in. x 9.5 in.) - General Warehouse No. 2005000.

Commercial Lime Slurry

♦ safety goggles

♦ 2 L (1/2 gal.) large-mouth (89 mm [3.5 in.] diameter) polyethylene bottle and a polypropylene or phenolic screw cap – Nalge Company No. 2234-0020

♦ plastic electrical tape, PVC 19 mm (0.75 in.) wide

♦ cloth rag or shop towel.

Sampling Procedures

♦ Hydrated Lime • from loaded tank trucks

CAUTION: These trucks are pressurized for unloading, and attempts to open a pressurized top hatch could be fatal. Therefore, the contractor should make the load available for sampling prior to pressurization, with top hatches open. If the truck is offered for sampling pressurized, it shall be the responsibility of the contractor to bleed off the pressure and open the top hatches.

The following describes the sampling procedure for hydrated lime in powdered form as bulk hydrate.

Sampling Hydrated Lime from Loaded Tank Trucks Step Action

1 Collect a 2 L (1/2 gal.) sample for analysis. To avoid contamination by moisture or other materials, take samples from the truck prior to unloading. CAUTION: These trucks are pressurized for unloading, and attempts to open a

pressurized top hatch could be fatal. Therefore, the contractor should make the load available for sampling prior to pressurization, with top hatches open. If the truck is offered for sampling pressurized, it shall be the responsibility of the contractor to bleed off the pressure and open the top hatches.

2 The preferred sampling method is rodding material from the top of the truck through open hatches.

3 If the material in the truck cannot be sampled prior to unloading, then various optional sampling methods may be used, provided the sample is representative, and is not allowed to become contaminated by moisture or mixing with base or other road material. Less desirable methods include: ♦ scoop samples obtained through open top hatches ♦ as discharged from tank trucks ♦ hose discharge ♦ dry application "catch-pan" method.

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4 Do not scoop samples from material applied on roadway due to likelihood of contamination.

Bulk hydrated lime should be sampled at the rate of one sample per 181.44 Mg (200 tons), unless otherwise directed. This represents roughly one trailer of every ten shipped. The trailer to be sampled should be selected at random and identified on the sample ticket by seal number, name of producer and date sampled. The seal numbers of the other nine loads need not be listed. Samples shall not be combined.

Lime becomes contaminated by exposure to the atmosphere. To preserve the quality of samples, use the paintbrush to clear the sample bucket rim of lime collected during sampling, so an effective seal is obtained.

Two bulk samplers are listed. The top hatch device samples the upper portion of the load through the top hatches of a bulk transport. The unit is inserted with the air hole in the rubber stopper open. When withdrawing the tube, hold the hole shut with a thumb.

The bottom sampler is designed to obtain bottom samples, but may be used to take samples at various levels within the truck, or for other sampling tasks. The device is inserted at the sampling level desired with its port closed. Then the port is opened, the tube is slid back and forth, the port is closed, and the tube is removed. Lime is released from the tube by tapping the device and allowing the lime to exit from the top end into a sample bucket.

• from bag trucks

The following procedure describes sampling for hydrated lime in powdered form as bagged hydrate from bag trucks being loaded.

Sampling Hydrated Lime from Bag Trucks Step Action

1 Sample at least six sacks to represent each truck being shipped. 2 Sample at least four to six sacks from each lot being inspected and combine the material

to form a composite sample representing that lot. 3 Samples may be taken from the separate lots that comprise the whole if the entire lot

consigned for an individual truck is from several different warehouse lots. 4 ♦ Insert the bag sampling tube through the sack loading spout and take sufficient

diagonal roddings to insure a representative portion from each sack, without significantly reducing the volume.

♦ Take care not to puncture the sack with the sampling tube.

• from bagged shipments after delivery to warehouse or job site

The following procedure describes the sampling of hydrated lime in powdered form as bagged hydrate from warehouse or job site.

Sampling Hydrated Lime from Bagged Shipments after Delivery to Warehouse or Job Site Step Action

1 Use the bag sampling tube described in the equipment list to obtain a 2 L (1/2 gal.) sample from at least six sacks of material.

2 Select sacks for sampling from various points in the load or shipment, to collect a

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representative sample. 3 ♦ Insert the bag sampling tube through the sack loading spout and take sufficient

diagonal roddings to insure a representative portion from each sack, without materially reducing the poundage.

♦ Take care not to puncture the bottom or sides of the sack with the sampling tube.

♦ Quicklime in Crushed or Pebble Form

CAUTION: Quicklime is extremely hazardous and capable of inflicting severe caustic burns to skin, lung damage, and/or eye injury and blindness, if handled improperly. Personnel handling, sampling or testing quicklime should wear proper protective clothing, respirators, dust-proof goggles and waterproof gloves. • discharged from tank trucks

The following procedure describes sampling of quicklime in crushed or pebble form as discharged from tank trucks.

Sampling Quicklime (in Crushed or Pebble Form) as Discharged from Tank Trucks Step Action

1 Instruct the truck to pass over a collection device while unloading. CAUTION: Quicklime generates fines in transit. Since air-blown quicklime fines are

hazardous, quicklime is usually unloaded at the job site by gravity feed through ports at the bottom of each compartment on the truck. Most trucks will be equipped with 3 or 4 such compartments, which are usually opened to discharge simultaneously.

2 Collect samples from the midpoint of the unloading of the truck. NOTE: Specifications limit the amount of fines in the sample and include sizing

requirements. The sizing and gradation of the sample taken shall be representative of the load. Quicklime fines tend to settle to the bottom of the compartments and the initial discharge usually contains a higher percentage than the remainder of the load. The top of the load tends to contain the coarsest material. The center of the discharge run represents the entire load.

3 ♦ The sampler should pick up the collection device and carefully transfer the entire sample to a plastic sample bag.

♦ Close and seal the bag with tape or rubber band and place in a sample bucket for transport.

♦ The bucket should be marked "caustic" and "quicklime." 4 Ship samples by motor freight only.

NOTE: Do not ship by bus, parcel post, air, or rail. This is hazardous material, which, upon contact with water and combustibles, can cause fires. For this and other safety-related reasons, the carriers listed have refused to accept the material for shipment.

• from tank trucks

The following procedure describes the sampling of quicklime in crushed or pebble form from tank trucks.

Sampling Quicklime (in Crushed or Pebble Form) from Tank Truck Step Action

1 ♦ Collect samples from the top of the trucks. ♦ Dig below the surface of the pebble quicklime at least 203 mm (8 in.) and dip a

sample with a 4 L (1 gal.) bucket.

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Sampling Quicklime (in Crushed or Pebble Form) from Tank Truck Step Action

♦ A sample should be a minimum of 3 L (3/4 gal.). 2 ♦ Carefully transfer the entire sample to a plastic sample bag.

♦ Close and seal the bag with tape or rubber band and place in a sample bucket for transport.

♦ The bucket should be marked "caustic" and "quicklime." 3 Ship samples by motor freight only.

NOTE: Do not ship by bus, parcel post, air, or rail. This is hazardous material, which, upon contact with water and combustibles, can cause fires. For this and other safety-related reasons, the carriers listed have refused to accept the material for shipment.

♦ Commercial Lime Slurry • from the truck

The following procedure describes the sampling of commercial lime slurry from the truck.

Sampling Commercial Lime Slurry from the Truck Step Action

1 Draw the sample from the permanent sampling port located concentrically at the rear of the truck. NOTE: The sampling port shall consist of a 13 mm (0.5 in.) minimum, quick acting valve

fitted to a 19 mm (0.75 in.) diameter pipe and outlet spout. 2 Open the sampling valve quickly and completely during sampling. 3 Half fill the plastic sample jug, to permit agitation and testing. 4 Tightly seal the jug and tape the cap to avoid leakage during transport.

NOTE: The sampling, capping and sealing of the slurry sample shall be the sole responsibility of the truck driver by direct request from a TxDOT representative. • from the plant

The following procedure describes the sampling of commercial lime slurry from the plant.

Sampling Commercial Lime Slurry from the Plant Step Action

1 Collect sample from the sampling valve in the vertical riser from the slurry tank to the loading spout.

2 Observe the same consistency and sampling precautions as outlined above, in 'Sampling Commercial Lime Slurry from the Truck.'

3 Take a sample (1 per truckload) to represent a truckload. 4 Sampling must be witnessed by a TxDOT representative.

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Section 3 Part II, Testing Hydrated Lime

This part discusses the method for testing High Calcium Type Hydrated Lime, Type A, and is based on the presence of the following constituents in the product: calcium hydroxide, calcium oxide or water, calcium carbonate and inert matter as silica dioxide.

Apparatus

The following apparatus is required:

♦ electric muffle furnace at 1093 ± 11 °C (2,000 ± 20 °F)

♦ platinum crucibles, low-form, wide-bottom type, 30 cc capacity

♦ tongs for use with muffle furnace, 508 mm (20 in.) length

♦ hard-surfaced temperature resistant board

♦ vacuum desiccator

♦ indicating type silica-gel desiccant

♦ analytical balance, for rapid weighing, with a minimum weighing capacity of 100 g. Balance must meet the requirements of Test Method "Tex-901-K, Verifying the Calibration of Weighing Devices Used in Laboratory Tests"

♦ top loading balance, for rapid weighing, with a minimum weighing capacity of 2000 g. Balance must meet the requirement of Test Method "Tex-901-K, Verifying the Calibration of Weighing Devices Used in Laboratory Tests"

♦ weighing boats

♦ spatula

♦ balance brush, camel's hair type

♦ tall form beakers, 400 mL (13.5 fl. oz.), borosilicate type glass

♦ buret 100 mL (3.4 fl. oz.) capacity, of borosilicate glass, with a 50 mL (1.7 fl. oz.) bulb at the top and 50 mL (1.7 fl. oz.) graduated tube. Burets must comply with requirements in ASTM E 287-94

♦ buret, 50 mL (1.7 fl. oz.) capacity, to have 0.1 mL (0.003 fl. oz.) subdivisions

♦ magnetic type stirrer

♦ stopwatch to register up to 30 minutes

♦ plastic tubing, 9.5 mm (3/8 in.) ID, 3 mm (1/8 in.) wall thickness, of suitable length. fitted with a Bunsen "fan-type" burner attachment at the outlet end of the hose

♦ 0 to 0.207 MPa (0 to 30 psi) water pressure gauge, 76 mm (3 in.) diameter face, with 9.5 mm (0.375 in.) IPS female thread fitting

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♦ set of standard U.S. sieves with the following sizes: No. 6 and No. 30 which meets the requirements of Test Method "Tex-907-K, Verifying the Accuracy of Wire Cloth Sieves"

♦ pH meter having an accuracy of ± 0.1 pH unit or better, with automatic temperature compensator jacks for automatic temperature control

♦ pH meter electrode, standard combination type

♦ pH meter reference electrode filling solution, KCl, 4 M saturated with AgCl.

Materials

The following materials are needed:

♦ potassium hydrogen phthalate

♦ bromophenol blue, 3', 3", 5', 5" Tetrabromophenolsulfonephthalein, to meet ACS specifications

♦ hydrochloric Acid (HCL), 36.5 to 38.0 % to meet ACS specifications

♦ phenolphthalein powder, to meet ACS specifications

♦ sodium borate, 10-hydrate, crystal or other to meet ACS specifications

♦ sodium hydroxide, 50% solution.

Special Solution Required

1.0 ± 0.0005 N sodium hydroxide solution.

Preparing 1.0 N Sodium Hydroxide Solution

The following procedure describes the preparation of a 1.0 N sodium hydroxide solution.

Preparing 1.0 N Sodium Hydroxide Solution Step Action

1 Fill a 19 L (5 gal.) plastic container 1/2 to 2/3 with de-ionized water. 2 Add 967.6 mL (32.72 fl. oz.) of 50% NaOH.

NOTE: Add the caustic to a sizable portion of water so the heat evolved is dissipated without being concentrated to avoid hazardous spattering.

3 Mix for 5 to 10 minutes. 4 Bring to 18.5 L (4.8 gal.) mark on the container. 5 Stir for at least 6 hours; preferably 12 hours. 6 Standardize with potassium hydrogen phthalate.

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Standardizing 1.0 N Sodium Hydroxide Solution

The following procedure describes the standardization of a 1.0 N sodium hydroxide solution.

Standardizing 1.0 N Sodium Hydroxide Step Action

1 Transfer 50 mL (1.7 fl. oz.) of the Sodium Hydroxide solution to a 50 mL (1.7 fl. oz.) Class A buret.

2 Weigh 7.5 to 8.5 g of potassium hydrogen phthalate onto a weighing boat. 3 Transfer the weighed material to a 400 mL (13.5 fl. oz.) tall-form beaker. 4 Add 185 mL (6.3 fl. oz.) of deionized water and mix. 5 Add five drops of phenolphthalein indicator solution. 6 Titrate with the sodium hydroxide solution to a visual end point of light pink, which will persist for

at least 60 seconds. 7 Record the amount of sodium hydroxide used. 8 Calculate the normality.

Calculations

The following calculations describe how to adjust the Sodium Hydroxide solution to achieve a 1.0 N Sodium Hydroxide solution.

. ( ).

Wt of Potassium Hydrogen Phthalate in gNormality of NaOHmL of NaOH required 0 204228

NOTE: The sodium hydroxide solution may need to be adjusted, by dilution with deionized water or addition of 50% sodium hydroxide, to reach a normality of 1.0000 ± 0.0005 N. If the normality is not within these limits, adjust.

♦ If Base is TOO Weak: • For example, if 18.5 L (4.9 gal.) of 0.9907 N solution needs to be strengthened to

1.0000 N, calculate how much 50% sodium hydroxide to add: • 18.500 x 0.991 = 18.334 • 18.500 - 18.334 = 0.166 • x 52.3 = 8.68 mL (0.29 fl. oz.) of 50% NaOH solution needed.

♦ If Base is TOO Strong: • For example, if the 18.5 L (4.9 gal.) of 1.021 N sodium hydroxide solution needs to

be weakened to 1.0000 N, calculate how much deionized water to add: • 18.500 x 1.021 = 18.888 • 18.888 - 18.500 = 0.388 L or 388 mL (13 fl. oz.) of deionized water needs to be

added.

After all adjustments have been made, standardize the resulting solution.

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Special Solution Required

1.0 ± 0.0005 N hydrochloric acid solution compared with the standardized sodium hydroxide solution.

Preparing 1.0 N Hydrochloric Acid Solution

The following procedure describes the preparation of a 1.0 N Hydrochloric Acid solution.

Preparing 1.0 N Hydrochloric Acid Solution Step Action

1 Fill a 19 L (5 gal.) plastic container 1/2 to 2/3 full with deionized water. 2 Add 1625 mL (55.0 fl. oz.) of concentrated hydrochloric acid. 3 Add sufficient water to bring the total volume to 19 L (5 gal.).

NOTE: Add the acid to a sizable portion of water so the heat evolved is not being concentrated in a small volume of liquid. Such concentration can cause hazardous spattering of hot acid, fuming, etc.

4 Stir the solution at least 4 hours; preferably 12 hours. 5 Standardize against the sodium hydroxide.

Standardizing 1.0 N Hydrochloric Acid Solution

The following procedure describes the standardization of a 1.0 N hydrochloric acid.

Standardizing 1.0 N Hydrochloric Acid Solution Step Action

1 Transfer 40 mL (1.4 fl. oz.) of the acid solution into a 400 mL (13.5 fl. oz.) tall beaker using a buret for accuracy, and record the volume.

2 Add 140 mL (4.7 fl. oz.) of deionized water. 3 Add five drops of phenolphthalein indicator. 4 Titrate with the sodium hydroxide solution to a visual end point of light pink, which will persist

for at least 60 seconds. 5 Calculate the normality.

Calculations

The following calculations describe how to adjust the hydrochloric acid solution to achieve a 1.0 N hydrochloric acid solution.

mL of NaOH required N of NaOH usedNormality of HCLmL of HCL used

×=

NOTE: The hydrochloric acid solution may need to be adjusted by dilution with deionized water or addition of concentrated HCl to achieve a normality of 1.0000 ± 0.0005 N. If the normality is not within these limits, adjust.

♦ If Acid Solution is TOO Weak:

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• For example, if 19.7 L (67 fl. oz.) of 0.9908 N solution needs to be strengthened to 1.0000 N, calculate how much concentrated HCl to add:

• 19.700 x 0.991 = 19.523 • 19.700 - 19.523 = 0.177 • 0.177 x 82.5 = 14.6 mL (0.49 fl. oz.) of concentrated HCl needed.

♦ If Acid Solution is TOO Strong: • For example, if 19.7 L (1 gal.) of 1.024 N solution needs to be weakened to 1.0000

N, calculate how much deionized water to add: • 19.700 x 1.024 = 20.1732 • 20.173 - 19.700 = 0.473 L or 473 mL (16.76 fl. oz.) of deionized water needs to be

added.

Special Solution Required

♦ pH Buffer Solution • pH value 4.01 at 25 °C (77 °F), 0.05 M potassium hydrogen phthalate solution.

Preparing pH Buffer Solutions

♦ pH Value at 4.01 at 25 °C (77 °F), 0.05 M potassium hydrogen phthalate solution

The following procedure describes the preparation of a 4.0 pH Buffer solution.

Preparing 4.0 pH Buffer Solution Step Action

1 Weigh 10.21 ± 0.05 g of primary standard reagent grade potassium hydrogen phthalate. 2 To a 1000 mL (34 fl. oz.) volumetric flask add 500 mL (16.9 fl. oz.) deionized water. 3 Transfer and dissolve the reagent in the volumetric flask. 4 Dilute to 1000 mL (34 fl. oz.).

The pH of the potassium hydrogen phthalate solution at various temperatures should be:

pH of Potassium Hydrogen Phthalate Temperature °C (°F) pH of 0.05 M Potassium Hydrogen

Phthalate Solution 15 (59) 3.999 20 (68) 4.002 25 (77) 4.008 30 (86) 4.015 35 (95) 4.024 40 (104) 4.035

♦ pH Value 9.18 at 25 °C (77 °F) , 0.01 M NaB4O7 (Borax) Solution

The following procedure describes the preparation of a 9.0 pH Buffer solution.

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Preparing 9.0 pH Buffer Solution Step Action

1 Weigh 3.81 ± 0.01 g of reagent-grade sodium tetraborate decahydrate. 2 To a 1000 mL (34 fl. oz.) volumetric flask add 500 mL (16.9 fl. oz.) deionized water. 3 Transfer and dissolve the reagent in the volumetric flask. 4 Dilute to 1000 mL (34 fl. oz.).

The pH of the borax solution at various temperatures should be:

pH of Borax Solution Temperature °C (°F) pH of 0.01 M Borax

Solution 15 (59) 9.276 20 (68) 9.225 25 (77) 9.180 30 (86) 9.139 35 (95) 9.102 40 (104) 9.068

Special Solution Required

Phenolphthalein Indicator Solution

Preparing Phenolphthalein Indicator Solution

The following procedure describes the preparation of a phenolphthalein indicator solution.

Preparing a Phenolphthalein Indicator Solution Step Action

1 Weigh 0.5 g of powdered phenolphthalein, ACS grade. 2 In a 200 mL (6.8 fl. oz.) beaker, dissolve the phenolphthalein in 50 mL (1.7 fl. oz.) of 200 proof

(absolute) ethyl alcohol. 3 Add 50 mL (1.7 fl. oz.) of deionized water and stir.

Special Solution Required

Bromophenol Blue Indicator Solution

Preparing Bromophenol Blue Indicator Solution

The following procedure describes the preparation of Bromophenol Blue Indicator Solution.

Preparing Bromophenol Blue Indicator Solution Step Action

1 Weigh 0.1 g of powdered Bromophenol blue.

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2 In a 250 mL (8.5 fl. oz.) volumetric flask, dissolve the Bromophenol blue in 7.5 mL (0.25 fl. oz.) of 0.02 N NaOH solution.

3 Dilute the mixture to 250 mL (8.5 fl. oz.) and stir.

Preparing Hydrated Lime Sample

The following procedure describes the preparation of Hydrated Lime.

Preparing Hydrated Lime Step Action

1 Mix the sample well for one to two minutes. 2 Invert and shake again at least three times. 3 Remove the bucket lid and scoop out enough material to fill a sample vial ½ to 3/4 full. 4 After sample withdrawal, close the bucket and sample vial to minimize atmospheric

contamination.

NOTE: Moisture in the air tends to air slake calcium oxide, converting it to calcium hydroxide, which tends to react with carbon dioxide in the air to form calcium carbonate, thus degrading the quality of the sample by reducing the active lime content.

Testing Procedures

♦ Titrimetric Analysis of Hydrated Lime

The following procedure describes the titrimetric analysis of various alkaline components of the Hydrated Lime sample.

Titrimetric Analysis of Hydrated Lime Step Action

1 ♦ Weigh out on an analytical balance 2.804 ± 0.0050 g of lime from the sample vial. ♦ Reseal the vial.

2 Add 150 mL (5.1 fl. oz.) of deionized water to a 400 mL (13.5 fl. oz.) tall-form beaker. 3 Quantitatively transfer the weighed sample to the 400 mL (13.5 fl. oz.) tall-form beaker.

NOTE: To minimize loss of sample, transfer material slowly. 4 Add a stirring magnet and slowly stir the sample mixture for 30 to 90 seconds. 5 Calibrate the pH meter using the 4.0 and 9.0 buffer solutions. 6 Titrate the sample with the first 50 mL (1.7 fl. oz.) of the 1.0 N HCl solution to an end point

of less than 9.0 on the pH meter. Titrate as rapidly as the reaction rate of the sample will allow. NOTE: The rate of addition is dictated by the response or reaction time indicated by the

sample. Lime samples will vary in response to additions of titrant. An excess of titrant will cause localized pooling of titrant. Carbon dioxide gas may be observed from the reaction of acid with calcium carbonate. This reaction occurs at a pH of less than 5.4. In the titration to pH 8.3, rapidly add the titrant, but slow enough to keep the pH greater than 6.0 at all times. With addition of titrant the pH will drop and then, in most cases, recover or rise to a higher value as more solids dissolve and enter into the reaction.

7 Decrease the rate of titration to a rapid drop rate until a pH of between 6.0 and 9.0 is reached and persists for at least 30 seconds.

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8 Use smaller increments of titrant to maintain a pH slightly less than 8.3. As the pH increases, add more titrant until 8.3 or slightly less persists for 60 seconds. NOTE: The end point for the titration to pH 8.3, or slightly less, is the point at which the

addition of one two-drop increment of titrant produces a pH meter indication of 8.3, or slightly less, when observed exactly 60 seconds after addition.

9 Record the volume of titrant required to reach this end point. 10 Continue to add HCl to the sample in the beaker to a point where a total of 100 mL (3.4 fl.

oz.) of titrant has been added to the sample since the start of titration. NOTE: The sample mixture contains a "measured excess" of HCl.

11 Record the total volume of acid added. The volume will always be 100 mL (3.4 fl. oz.).

♦ Back-Titration to pH 4.4 with NaOH

The following procedure describes the back-titration to pH 4.4 with NaOH.

Back-Titration to pH 4.4 with NaO Step Action

1 Titrate sample with excess hydrochloric acid with the 1.0 N NaOH solution to a pH of 4.4, or slightly greater than 4.4 when observed exactly 10 seconds after a one-drop addition of titrant.

2 Record the NaOH volume at the first occurrence of the end point.

♦ Determining Percent Loss on Ignition for Hydrated Lime

The following procedure describes determining Percent Loss on Ignition in a Hydrated sample.

Determining Percent Loss on Ignition for Hydrated Lime Step Action

1 Weigh a platinum crucible using an analytical balance, record the weight, then tare balance. 2 Weigh out a 2.9 to 3.1 g sample in a tared platinum crucible. 3 Place in an electric muffle furnace at 1093 ± 11 °C (2,000 ± 20 °F) for a minimum of three

hours. 4 Remove the crucible from the muffle furnace and place it on a hard-surfaced asbestos board. 5 Transfer the crucible to a vacuum desiccator for cooling. Allow 20 minutes for cooling.

NOTE: If several samples are run simultaneously, remove all samples from furnace and place on the asbestos board, then transfer to the desiccator and replace the lid with the vacuum stopcock open. The heated air will expand through the opening for several seconds, then the stopcock should be closed.

6 Weigh cooled sample as rapidly as possible to prevent hydration of residue, and record weight to the nearest 0.01 g.

Screen Analysis

The following procedure describes the Screen Analysis in a Hydrated Lime Sample.

Screen Analysis for Hydrated Lime Step Action

1 Weigh the remainder of the sample in the 4 L (1 gal.) sample bucket and screen the entire sample. 2 Weigh the screen analysis sample to the nearest 0.1 g.

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3 Water wash the sample through the No. 30 sieve. NOTE: Apply the wash water in a fantail spray pattern from the 9.5 mm (3/8 in.) ID plastic tubing

fitted with a Bunsen "fan type" burner attachment at the outlet. Monitor the water pressure with a water gauge at 83 ± 2 kPa (12 ± 0.3 psi).

4 Continue washing until the water coming through the sieve is clear. NOTE: Continue washing up to 30 minutes if milkiness persists.

5 Oven-dry the residue on each sieve for a period of one hour at a temperature of 100 ± 5 °C (212 ± 10 °F).

6 Remove screen from oven and weigh on an analytical balance to the nearest 0.01 g.

Calculations

Limits for Sample Weight and Titration Solutions:

Sample Wt. 2.804 ± 0.0050 g,

♦ Acid 1.000 N ± 0.0005 N

♦ Base 1.000 N ± 0.0005 N.

Use the following tables to convert milliliters (ounces) of acid or base to component equivalents with a worksheet that may be used.

Procedure

The following procedure describes how to complete a Hydrated Lime sample worksheet.

♦ Milliliters of HCL to pH 8.3 is equivalent to the hydrate alkalinity. Record this value and the corresponding uncorrected Ca(OH)2 from the 'Uncorrected Calcium Hydroxide Value' table.

♦ Total milliliters HCL added, 100, less the milliliters of NaOH required to obtain a pH of 4.4 is equal to the total alkalinity. Record this value and subtract hydrate from total alkalinity to give carbonate alkalinity. From the 'Calcium Carbonate Value as CaCO3' table obtain equivalent calcium carbonate and record this value.

♦ Calculate the loss on ignition of the sample. The inert value can now be calculated by subtracting the sum of the loss on ignition and the total alkalinity from 100. Record the inert value (or an average or assumed inert value based on previous analysis of lime from a given source).

♦ The uncorrected Ca(OH)2, CaCO3, and the inert value are then totaled. If the total is less than 100%, the difference is free water. If the total is greater than 100%, quicklime is present. The following examples demonstrate each situation: • Example where CaO is present:

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Uncorrected Ca OHCaCOAssumed inert

SubtotalCaCO x

Uncorrected Ca OHCa OH Correction Value

Analysis is shown asCa OHCaCOCaO

Total

( ) ...

.

. .% . . .

( ) .( ) .

.:( ) .

..

.

2

3

2

2

2

3

94 83 12 2

100 1

100 1 100 0 10 1 3 11 0 3

94 80 4

94 4

94 43 10 3

100 0

===

− == =

== −

===

=

• Example where H2O is present:

Uncorrected Ca OHCaCOAssumed Inert

TotalH O

Analysis is shown asCa OHCaCOAssumed InertH O

Total

( ) ...

.% . .

:( ) .

...

.

2

3

2

2

3

2

93 04 610

98 6100 98 6 14

93 04 61014

100 0

===

== − =

====

=

♦ If free water is present, the uncorrected hydrate alkalinity will be actual hydrate alkalinity as Ca(OH)2

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♦ For uncorrected Calcium Hydroxide value:

Uncorrected Calcium Hydroxide Value mL (fl. oz.) of Acid and

Hydrated Alkalinity % Ca(OH)2

68.0 (2.29) 89.8 69.0 (2.33) 91.2 70.0 (2.37) 92.5 71.0 (2.40) 93.8 72.0 (2.43) 95.1 73.0 (2.47) 96.4 74.0 (2.50) 97.8 75.0 (2.54) 99.1

factor = 1.32126

♦ For Calcium Carbonate Value As CaCO3 • Whole mL difference between two end points:

Calcium Carbonate Value as CaCO3 Carbonate Alkalinity CaCO3

0.0 0.0 1.0 1.8 2.0 3.6 3.0 5.4 4.0 7.1

factor = 1.78479

♦ For correction for calcium hydroxide value when CaO is present:

Correction for Calcium Hydroxide Value (Subtotal-100%) (Ca[OH]2 Correction

Value) 0.1 0.4 0.2 0.8 0.3 1.2 0.4 1.6 0.5 2.1 0.6 2.5 0.7 2.9 0.8 3.3 0.9 3.7 1.0 4.1 1.1 4.5 1.2 4.9

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Amount of subtotal over 100%

♦ For %Quicklime: • When quicklime is present – % CaO = (Subtotal - 100%) x 3.11

♦ For %Free water: • When free water is present – 100%-Subtotal

Proportional Parts mL (fl. oz.) acid %Ca(OH)2

0.1 (0.0034) 0.1 0.2 (0.0068) 0.3 0.3 (0.0101) 0.4 0.4 (0.0135) 0.6 0.5 (0.0169) 0.7 0.6 (0.0203) 0.8 0.7 (0.0237) 1.0 0.8 (0.0271) 1.1 0.9 (0.0304) 1.3

factor = 1.32126

Use this chart to obtain a corrected calcium hydroxide value by subtracting the Ca(OH)2 correction value obtained from the uncorrected calcium hydroxide value.

Proportional Parts Fractional Carbonate

Alkalinity CaCO3

0.1 0.2 0.2 0.4 0.3 0.5 0.4 0.7 0.5 0.9 0.6 1.1 0.7 1.3 0.8 1.4 0.9 1.6

factor = 1.78479

Use the above chart if the sub-total (uncorrected calcium hydroxide value + calcium carbonate value + assumed inert value) is greater than 100%. This means that CaO is present and not free water.

If the sub-total is less than 100%, then the uncorrected calcium hydroxide value is assumed correct. Calcium hydroxide and free water are present.

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Optional Indicator Method for the Titrimetric Analysis of Various Alkaline Components of the Sample

Use this method in lieu of the prescribed pH meter method. However, for all referee tests, or in cases of dispute, the prescribed pH meter method will be considered the official method.

In some cases, impurities such as aluminum compounds will prevent or hinder the appearance of the color change in the back-titration portion of this optional method. If such a difficulty is encountered with a particular sample, use the prescribed pH meter method.

The following procedure uses the optional indicator method. A few exceptions apply.

Titration Procedures

♦ Phenolphthalein End Point with HC1

The following procedure describe the Titration to Phenolphthalein End Point with HCl.

Titration to Phenolphthalein End Point with HCl Step Action

1 At the start of titration add five drops of phenolphthalein indicator to the sample mixture. 2 Titrate to the point where the color of the solution changes temporarily from pink to clear. 3 Wait for the pink color to return. 4 Add titrant until the color change appears imminent. 5 Add acid in four-drop increments until the pink coloration disappears for 35 seconds. 6 Add acid in two-drop increments until the end point described below is reached.

NOTE: The end point is the failure of the mixture to regain its pink coloration during 60 seconds after the last addition of the titrant. Once the end point has been reached, the reappearance of pink color is ignored. The phenolphthalein end point is the equivalent to the pH 8.3 end point described in the official pH meter method of titration.

♦ Titration to "Measured Excess" of HC1

The following procedure describes the titration to "measured excess" of HC1.

Titration to "Measured Excess" of HC1 Step Action

1 After the end point has been reached, add a "measured amount" of hydrochloric acid. 2 Add Titrant to a total volume of 100 mL (3.4 oz).

♦ Back Titration to the Bromophenol Blue end Point with NaOH

The following procedure describes the back titration to the Bromophenol blue end point with NaOH.

Back Titration to the Bromophenol Blue End Point with NaOH Step Action

1 To the sample mixture, add 2.0 mL (0.07 fl. oz.) of Bromophenol blue indicator.

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2 Titrate until the color of the mixture changes from yellow to blue with a slight tinge of purple and maintains the blue color for 10 seconds after a one-drop addition of titrant.

3 Record the end point. NOTE: The endpoint shall be recorded at pH 4.4, when using a pH meter.

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Section 4 Part III, Testing Commercial Lime Slurry

This part discusses the method for testing high calcium type commercial lime slurry, Type B, and assumes that the principal constituents present in the product are calcium hydroxide water, calcium carbonate, and inert matter such as silica dioxide.

Apparatus

All equipment listed under 'Part II, Testing Hydrated Lime' are required for the testing of slurry, with these additions:

♦ eyedropper, large bore polyethylene

♦ stainless steel weight-per-gallon cup with tare weight

♦ 480 mL (1 pt.) polyethylene bottles with 28 mm (1.10 in.) screw caps.

Materials

Use chemical solutions listed for the testing of bulk hydrate or powdered lime in “Part II, Testing Hydrated Lime' of this procedure.

Procedures

♦ Preparing Lime Slurry Sample

The following procedure describes the preparation of a lime slurry sample.

Preparing Lime Slurry Sample Step Action

1 Set the slurry jug in a roller and agitate for 3-4 hours. 2 Immediately pour a representative sample into a 480 mL (1 pt.) polyethylene bottle with a

screw top. NOTE: Clean the threaded portion of the bottles and the inside threads of the cap. If slurry is

allowed to remain on these places, an air tight seal will not be obtained and the slurry may be subjected to dehydration.

♦ Determining Lime Slurry Bulk Density

The following procedure describes bulk density determination.

Determining Lime Slurry Bulk Density Step Action

1 From the 480 mL (1 pt.) bottle, rapidly pour slurry into a tared 4 L (1 gal.) weight-per-gallon cup to minimize settling. Fill the cup 1.6 mm (0.063 in.) from the top rim. NOTE: If final increments of slurry are added to the weight-per-gallon cup, recap the pint

bottle and re-agitate the sample before making the final addition. 2 Tap the bottom of the filled cup against a hard surface to remove air bubbles.

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3 ♦ Place the lid on the cup, gently pressing it into place. Excess slurry will flow out the small center opening in the top.

♦ Clean off top. 4 Place the weight-per-gallon cup on a top loader balance and weigh the cup and its contents to

the nearest 0.1 g. 5 Subtract the tared value of the cup and lid. Divide the result by 10. 6 Report this value as the bulk density of the slurry expressed in kg/L (lbs./U.S. gal.).

Selection of the Appropriate Amount of Slurry Sample for Titrimetric Analysis: • Use 'Range of Sample Weights for Analysis of Slurries – No.1, No. 2, and No. 3

to determine the amount of slurry lime needed for titrimetric analysis from the bulk density of the slurry. This quantity will contain the equivalent of 2.9 to 3.1 g (0.10 ± 0.11 fl. oz.) of dry lime.

Figure Error! No text of specified style in document.-1. Range of Sample Weights for Analysis of Slurries - No. 1.

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Figure Error! No text of specified style in document.-2. Range of Sample Weights for Analysis of Slurries - No. 2.

Figure Error! No text of specified style in document.-3. Range of Sample Weights for Analysis of Slurries - No. 3.

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Selection of the Appropriate Amount of Slurry Sample for Determining Loss on Ignition: • Use 'Range of Sample Weights for Analysis of Slurries – No. 1.' to determine the

range of sample weights needed to determine loss on ignition. This quantity will contain the equivalent of 2.9 to 3.1 g of dry lime.

♦ Titrimetric Analysis of Various Alkaline Components of Lime Slurry

The following procedure describes the titrimetric analysis of various alkaline components of the Lime Slurry Sample.

Titrimetric Analysis of Various Alkaline Components of Lime Slurry Step Action

1 Pour the required weight of slurry sample, as determined above, in a 400 mL (13.5 fl. oz.) tall-form beaker.

2 Slowly add enough distilled water to bring the volume of mixture to 150 mL (5.0 fl. oz.). Add a stirring bar and place the beaker on a stirring plate.

3 ♦ Insert a pH probe and titrate immediately, adding the first 50 mL (1.7 fl. oz.) of 1.0 N HCl rapidly.

♦ Continue to add titrant at a rapid drop rate until the pH indication of 9 or slightly less is obtained.

NOTE: A suitable rapid drop rate is approximately 12 mL/min (0.41 fl. oz./min.). 4 After a momentary pH indication of 9 is reached, add titrant at the rate of approximately 2

mL/min (0.07 fl. oz./min.) until the pH is close to 8.5. 5 Now add acid in four-drop increments to a pH of 8.3 or less for approximately 35 seconds. 6 Then add two-drop increments until the end point of 8.3 or slightly less for 60 seconds is

reached. NOTE: End point is reached when the addition of one two-drop increment of titrant reaches a

pH of 8.3 or slightly less for exactly 60 seconds. The first occurrence is the final end point.

7 Record the volume of titrant used to reach the end point.

♦ Titration of Lime Slurry to "Measured Excess" of HCl

The following procedure describes the titration to "measured excess" of HCl.

Titration of Lime Slurry to "Measured Excess" of HCl Step Action

1 After the 8.3 end point has been reached, add an excess of HCl to the sample for a total of 100 mL (3.4 fl. oz.) of titrant.

2 Record the total volume of titrant added to the sample since the beginning of the titration. It will always be 100 mL (3.4 fl. oz.).

♦ Back-Titration of Lime Slurry to pH 4.4 with NaOH

The following procedure describes the back-titration to pH 4.4 with NaOH.

Back-Titration of Lime Slurry to pH 4.4 with NaOH Step Action

1 Titrate the sample mixture plus the "measured excess" of HCl with 1.0 N NaOH to a pH of 4.4 or slightly greater.

2 When the pH of 4.4 is observed for 10 seconds, end point has been reached.

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♦ Determining Percent Loss on Drying and Subsequent Ignition of Lime Slurry

The following procedure describes the determination of percent loss on drying and subsequent ignition of a slurry sample.

Determining Percent Loss on Drying and Subsequent Ignition of Lime Slurry Step Action

1 Tare weight a platinum crucible and add the appropriate amount of slurry. Record that weight to the fourth decimal place.

2 Place the platinum crucible with slurry into a 100 °C (212 °F) drying oven for one hour. 3 Remove sample from oven and place in a muffle furnace at 1093 °C (2,000 °F) for two

hours. 4 Use long tongs and a glove to remove the crucible. Place it on an asbestos board and transfer

it to a desiccator to cool. 5 Allow to cool for 30 minutes. 6 Weigh the crucible and report.

♦ Screen Analysis of Lime Slurry

The following procedure describes the screen analysis of a Lime Slurry Sample.

Screen Analysis of Lime Slurry Step Action

1 Pour 2 L (2 qt.) of the well-mixed slurry from the two-gallon polyethylene bottle into a previously tared mixer bowl.

2 Weigh the slurry and record. 3 Under a hood, water wash the slurry through a No. 6 sieve, then a No. 30 sieve

simultaneously. 4 Follow the wet screen analysis method and equipment requirements described in the

screening of dry lime samples.

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Section 5 Part IV, Testing Type C Quicklime

This part discusses the method for testing of Quicklime, Type C.

CAUTION: Quicklime is extremely hazardous and capable of inflicting severe caustic burns to skin, lung damage, and/or eye injury. It can cause blindness if handled improperly. Personnel handling, sampling, testing, or working around quicklime should wear proper protective clothing, respirators and dust proof goggles to prevent injury.

Apparatus

All equipment items listed under 'Part II, Testing Hydrated Lime,' are required to test quicklime, with the following additions:

♦ laboratory grinder

♦ mechanical shaker, with timer, to accommodate 203 mm (8 in.) diameter sieves

♦ mixer with 4 L (1 gal.) capacity mixing bowl

♦ wire whip, Type D

♦ mechanical convection oven, with a capacity to maintain 100 ± 1 °C (212 ± 2 °F)

♦ sample splitter, (alternate slot type), two catch pans of appropriate size, and one pour pan

♦ sieves, (Nos. 6 and 30)

♦ Erlenmeyer flasks, 500 mL (16.9 fl. oz.)

♦ rubber stoppers, No. 10 size, no hole

♦ ointment type cans, 170 g, with lids.

Solutions

The following solutions are needed:

♦ sugar solution, freshly prepared, for each lime slurry sample

♦ phenolphthalein indicator solution

♦ deionized or distilled water

♦ hydrochloric acid, 1.0000 N ± 0.0005. Standardize with sodium hydroxide, 1.0000N. according to 'Part II, Testing Hydrated Lime.'

Preparing Solutions

♦ Sugar Solution

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The following procedure describes the preparation of a sugar solution for each lime slurry sample.

Preparing a Sugar Solution Step Action

1 Dissolve 60 g of granulated cane sugar in 120 mL (4.0 fl. oz.) of deionized or distilled water using a large stirring bar.

2 Add one (1) drop of phenolphthalein indicator. 3 Add 1.0 N sodium hydroxide, drop-wise, until a faint pink color is observed.

♦ Phenolphthalein Indicator Solution

The following procedure describes the preparation of a Phenolphthalein Indicator Solution.

Preparing a Phenolphthalein Indicator Solution Step Action

1 Dissolve 0.1 g of powdered phenolphthalein, ACS grade, in 50 mL (1.7 fl. oz.) of absolute ethyl alcohol.

2 Add 50 mL (1.7 fl. oz.) of deionized or distilled water.

Procedures

♦ Preparing Quicklime Sample

The following procedure describes preparing a quicklime sample.

Preparing a Quicklime Sample Step Action

1 Divide 4 L (1 gal.) of the sample into two portions through the splitter. 2 Cover and set aside one of the portions. 3 Measure 300 g of the remaining portion. 4 ♦ Grind the 300 g portion for chemical analysis.

♦ Transfer to a 170 g can and close tightly. 5 Measure 800 g from the remainder of this portion. 6 Cover and set aside. 7 Boil 100 mL (3.53 fl. oz.) deionized or distilled water for each sample.

NOTE: Protect all portions from contamination. Samples that contain flint or other extremely hard material should be crushed to pass through a 3.35 mm (1/8 in.) sieve in a jaw-type crusher prior to grinding.

♦ Chemical Analysis of Quicklime

The following procedure describes the chemical analysis of a quicklime sample.

Chemical Analysis of Quicklime Step Action

1 Weigh 2.8040 ± 0.0050 g of the ground sample in a weighing boat. 2 Transfer sample to a 500 mL (16.9 fl. oz.) Erlenmeyer flask containing 10 mL (0.34 fl. oz.)

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freshly boiled water. 3 Add an additional 50 mL (1.7 fl. oz.) boiled water to flask. 4 Stopper the flask with a No. 10 rubber stopper and swirl for a few seconds. 5 Place sample on a hot plate and boil for 2 minutes. 6 Remove sample from hot plate and cool to room temperature. 7 Add 150 mL (5 fl. oz.) sugar solution to the flask, stopper, and let stand for 15 minutes. Swirl

every 5 minutes. 8 Add 5 drops of phenolphthalein indicator solution. 9 Titrate the sample with the 1.0000 N hydrochloric acid until the first instance of pink color

disappears. 10 The amount of acid used is the percent by weight of "Active CaO" contained in the sample.

Report it to the nearest 0.1 %.

♦ Dry Sieve Analysis of Quicklime

The following procedure describes the dry sieve analysis of a quicklime sample.

Dry Sieve Analysis of Quicklime Step Action

1 Pass the 800 g portion, previously reserved, through a nest of sieves (No. 6 and No. 30) into a catch pan, in 200 g increments, while shaking the sieves. NOTE: Perform this operation under a hood, while wearing a dust/mist mask.

2 Weigh the amount caught in each sieve to the nearest 1 g, then recombine them for wet sieve analysis.

♦ Wet Sieve Analysis of Quicklime

The following procedure describes wet sieve analysis of a quicklime sample.

Wet Sieve Analysis of Quicklime Step Action

1 Add 2600 mL (87.9 fl. oz.) tap water to the mixer bowl, return to the mixer and attach the wire whip.

2 Weigh 800 g of quicklime, in increments of 80 g, into 10 tin containers. 3 ♦ Lower the wire whip, turn on the mixer and add one of the increments.

♦ Lower the shield. ♦ Let stir for 3 minutes.

4 Keep adding increments every 3 minutes. 5 Rinse the wire whip when finished. 6 ♦ Wash, with tap water, the reacted sample onto a No. 6 sieve.

♦ Be sure that none of the slurry sample is lost over the sides of the sieve. ♦ Water pressure must be 97 - 124 kPa (14 - 18 psi).

7 Continue to wash the sample for 30 minutes or until the wash water is clear, whichever occurs first.

8 After washing, place the sieve in the oven at a temperature of 100 °C (212 °F) for 1 hour. 9 After drying, cool the residue to room temperature and weigh it on a top loading balance to

the nearest 0.1 g.

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Calculations

The following describe data calculation for Sieve Analysis.

♦ For Wet Sieve Analysis

Report values to the nearest whole percent.

% .. limresidue retained on sieve in gwt of residue after slaking 100

wt in g of quick e being sieved= ×

♦ For Dry Sieve Analysis • Wt. in g of quicklime

% lim Re. lim

retained on sieveQuick e tained on Sieve 100wt in g of quick e being dry sieved

= ×

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Tex-600-J, Sampling and Testing Hydrated Lime, Quicklime, and Commercial Lime Slurry Section 6 — Archived Versions

Texas Department of Transportation 32 01/01 – 01/06

Section 6 Archived Versions

Archived versions of Test Method "Tex-600-J, Sampling and Testing Hydrated Lime, Quicklime, and Commercial Lime Slurry" are available through the following links:

♦ Click on 600-0899 for the test procedure effective August 1999 through December 2000.