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Structure of the Chemical IndustryEconomic FactorsDifferences between lab. & industryConversion & selectivity v.s yieldReactor TypesCatalyst Use and Material BalanceThe Chlor-alkali Industry

Raw material sources and SynGas.T-metal Catalysed Processes

CH304 Industrial Chemistry 2008 -2009 P.McArdle

The following topics will be covered

Sources:Principles of Industrial Chemistry, C.A. Clausen & G. Mattson, Wiley 1978Industrial Chemistry, C.A. Heaton, Blackie 1992.C & E News, (Weekly) American Chemical Society.

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Structure of The Chemical Industry

Before 1920 The Heavy Chemical Industry was mainly Inorganic

Important Large Scale Inorganic Processes

S + O2/catalyst = SO3 + H2O = H2SO4

N2 + 3H2 = 2NH3 ( + O2/catalyst = HNO3)

NaCl(soln.) electrolyse = Na + Cl2↑ Na hydrolysis = NaOH

The most Important Organic Industry in the early 20th century wassmall scale. Some aromatics were extracted from coal tar andconverted into dye stuffs. (Perkin)

Even as late as the 1930s Benzene was rare. Papers publishedinvolving benzene from that time usually thank the local Gas Works foraromatics obtained from coal tar. Benzene/toluene are now commonand are produced (by synthesis & distillation of oil) on a huge scale.

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The current position is very different. The production of organics is nowis now a very important industrial sector -Three important reasons for this change are -

1. A shortage of traditional materials during 1939-1945e.g. Natural Rubber supply to U.S.A was cut off by theJapanese invasion of Malaya. In response for exampleW.O.Carruthers, at Dupont, invented neoprene and nylon-6,6.

2. Availability of Cheap Arab Oil (especially Saudi Arabian oil)forced a change from Coal to Oil as a raw material.This led to the growth of the Petrochemical Industry.

3. Rise of the Pharmaceutical Industry. Elaborate Synthesis arenow carried out on a huge scale.E.g. Roche in Clarecastle in Co. Clare for many years used 1 tonne

of Mg (Grignard) per Naproxen. RMgX is an expensive reagent.

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nanaPhiladelphia88.15.9$7,837.00 Rohm and Haas111024.3$1,330.80 Allentown, Pa.87.913.9$8,820.30 Air Products9917.1$2,557.00 Danbury, Conn.10013$9,402.00 Praxair88

-16.7$523.70 Salt Lake City100-9.2$9,650.80 Huntsman Corp.672.9$1,411.00 Pittsburgh89.513.8$10,025.00 PPG Industries76

-43.2$820.00 The Woodlands, Texas1005.9$12,534.00 Chevron Phillips55-27.3$827.00 Houston56.5-17.1$16,165.00 Lyondell Chemical4414.2$4,153.00 Wilmington, Del.99.57.2$29,218.00 DuPont334.1$4,563.00 Irving, Texas9.48$36,826.00 ExxonMobil22

-18.5%$3,887.00 Midland, Mich.100%8.90%$53,513.00 Dow Chemical11

HEADQUARTERSCOMPANY20062007

Cge06Profits%ChemCge06Chem.salesRank

Top 10 US Chemical Companies

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898967971961Aluminum sulfate2,6032,6362,7262,604Ammonium sulfate4,1134,6185,3014,180Hydrochloric acid6,3017,6386,5585,733Ammonium nitrate6,6366,7106,4666,747Nitric acid, 100%7,9938,5199,6188,793Sodium hydroxide

10,24810,27512,32610,359Chlorine10,35910,14110,93710,466Ammonia10,70411,43711,51111,324Phosphoric acid, P2O5

35,95437,14738,02137,373Sulfuric acid2006200520042003

Thousands of Metric TonsTop 10 U.S. Inorganics

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3,4453,1663,7723,660Ethylene oxide

3,5593,5093,7363,397Cumene

4,8275,0425,3945,167Styrene

5,2865,2515,7795,578Ethylbenzene

5,4315,2675,7565,783Urea

7,6427,5748,7817,926Benzene (thousands of liters)

9,73211,30812,1639,994Ethylene dichloride

15,65015,49015,34513,939Propylene

25,02023,97425,68222,976Ethylene

2006200520042003

Thousands of Metric TonsTop 10 U.S. Organics

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Factors which push chemicals to the top ofproduction lists

Inorganic Chemicals Chemicals which are Involved in fertilizersor the chloralkali industry

Organic Chemicals which are involved in the production ofpolymers/plastics and use oil as feedstock.

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7.89.3$40,881.00$29,687.00$37,926.00$27,160.00Spain

6.23.7$44,856.00$31,139.00$42,250.00$30,041.00Italy

16.51.6$70,620.00$74,932.00$60,612.00$73,776.00U.K.

12.913$56,241.00$82,305.00$49,794.00$72,840.00Netherlands

7.92.8$75,063.00$88,281.00$69,568.00$85,877.00France

0.060.082$111,248.00$136,077.00$104,938.00$125,789.00Belgium

10.313.1$131,139.00$179,973.00$118,867.00$159,114.00Germany

IMPORTSEXPORTSIMPORTSEXPORTSIMPORTSEXPORTS$ MILLIONS

CHANGE, 2006-0720072006

European Chemical Trade

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BELGIUMSolvay €9,797

FINLANDKemira €3,151

FRANCEAir Liquide €11,662Rhodia €6,569

GERMANYBASF €46,89Bayer €29,484Degussa €13,985Lanxess €7,529

NETHERLANDSAkzo Nobel €16,036DSM €,642

SWITZERLAND (S.fr)Ciba $9,654Clariant $6,864Givaudan $2,156Lonza $1,756Syngenta, $7,269

UNITED KINGDOMBOC £8,431ICI £10,267

PHARMACEUTICALSFRANCESanofi-Aventis €31,615

SWITZERLAND (S.fr)Novartis $28,247Roche $25,163

UNITED KINGDOMAstra Zeneca £21,426GlaxoSmithKline £37,318

European Chemical Companies 2004 x 106

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3,7774,2574,3043,574Phosphoric acid 4,0103,5653,4063,082Sodium sulfate5,4026,0025,1653,784Hydrochloric acid

7,5756,9566,6093,874Sodium carbonate

7,6559,8299,9947,937Sodium hydroxide

10,29610,38210,3969,525Chlorine11,57711,25110,6908,962Hydrogen (mcm)

15,50016,60916,58412,746Sulfuric acid (c)20,92927,82427,11222,554Oxygen (mcm)21,00022,45722,32617,807Nitrogen (mcm)

2006200520042003

Thousands of Metric TonsTop 10 Europe Inorganics

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2,2162,0052,059724Phenol3,1653,2482,8782,009Methanol 3,7304,2764,262911Ethylbenzene4,1274,2824,382626Xylenes4,1744,0574,0173,295Formaldehyde 4,6604,9636,2203,215Styrene 5,5386,6466,0443,374Ethylene dichloride 6,0507,0897,9316,535Benzene

15,29115,40615,12314,708Propylene 21,19221,60021,40820,686Ethylene

2006200520042003

Thousands of Metric TonsTop 10 Europe Organics

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619.4TOTAL EMPLOYEES x 100017.0 Ireland (total)19.5Syngenta (Switzerland)29.3Solvay (Belgium)20.6Rhodia g (France)28.9Merck (Germany)5.7Lonza (Switzerland)

19.7Lanxess (Germany)9.7Kemira (Finland)

33.8ICI (U.K.) 5.9Givaudan (Switzerland)

24.5DSM (Netherlands)44.6Degussa (Germany)24.8Clariant b (Switzerland)19.3Ciba (Switzerland)43.4BOC International (U.K.)93.3Bayer (Germany) 82.0BASF (Germany)61.5Akzo Nobel (Netherlands)35.9Air Liquide (France)

EmploymentInEuropeanChemicalIndustry

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A Brief History of the Oil IndustryOriginally interested in converting the home lighting market fromwhale oil to kerosene. Gasoline was worthless until the internalcombustion engine was developed.Standard Oil 1868 (monopoly owned by J.D. Rockefeller)broken up by the U.S. government in 1911 into a series of smallercompanies. As share prices went up after the breakup Rockefellerwealth actually increased. Some of the new companies were:St.Oil N.J. = Exxon (Esso), St. Oil N.Y. = Mobile, St. Oil Cal. = SOCALetc. etc.

For many years the Saudi Arabian oil concession was run byAramco = (Exxon+Texaco+Socal) now called Saudi Aramco.The global oil industry was run for many years by“the seven sisters” Exxon, Texaco, Socal, Mobile, Gulf, Shell, B.P.Recently Exxon and Mobile have merged.

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Spindletop is a salt dome oilfield located in south Beaumont,Texas. On January 10, 1901,a well at Spindletop struck oilmarking the birthdate of themodern petroleum industry.At 100,000 barrels (16,000 m³)of oil a day, the gusher tripled U.S.oil production overnight. Some of thecompanies chartered to exploit thewealth of Spindletop, such as Gulf Oiland Texaco, are part of today'sChevron Corporation.

The First Oil Gusher

Hughes rotarygear drill head

The Latest PCDToothed drill head has black PolyCrystallineDiamond teeth

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Petrochemical Industry

Since oil Refineries produce a range of oil products from ethyleneto heavy diesel oil it became economic to locate chemical plantsclose to oil refineries. The oil refineries then supplied feedstockto chemical plants. This led to the development of PETROCHEMICAL complexes

Oil company Chemical companyOil well → Oil Refinery Chemical plants

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Economic Factors and The Chemical industry

To set up a Chemical Plant Resources are needed -1. To acquire the knowledge necessary to build plant2. To build plant3. To operate plant

1 + 2 = Capital Cost

3 = Production Cost

Capital Cost will be increased by the following1. Multiple reaction stages2. Extensive separation of product/ by product

N.B. distillation more expensive than filtration.3. Extremes of T & P4. The use of corrosive materials5. Solids handling more expensive than liquids or gases.

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Depreciation of Capital Investment

A chemical plant with large equipment and automatic controlwill in general not have a high labour cost for a high outputbut the plant will have a high obsolescence and depreciation characteristic.

The plant may have a short lifetime.

Production Cost (€/kg)Production cost will appear as € or cent /kg. Raw material (feedstock)cost is by far the most important contributor to production cost.The contribution of labour cost to production cost is small. Even a smallraw material price increase can have a very adverse effect on theprofitability of a chemical plant.

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Research and Development (R&D)The more money that is spent on R&D the better the final process.However there is no way to estimate optimum R&D spending.Scale will determine R&D.

Even a minor change in a large scale process could have hugeconsequences.Conclusions1. Small tonnage processes are not and will never be

highly developed.2. There are niche markets for small scale processes which

will never attract large companies.3. There is a very great incentive to build a huge plant.

N.B. R&D does not tend to happen in Ireland.Loctite (now owened by Henkel)– is an exception cyanoacrylate(super glue) was invented and developed in Dublin.The pharmaceutical companies do some Process Development in Ireland.

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Choice of a Process

The choice of process is not a simple matter as there are manyinter-related factors.

1. Selectivity of the process (Yield).2. Cost of Raw Material3. Cost of energy4. Can any by products be sold?

As and example consider Phenol production.

In general remember that laboratory type procedures are oftennot suitable for industry.No large scale process uses KMnO4 or K2CrO4 as oxidizingagents free air or Nitric acid are the more popular oxidizing agents.

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Industrial Chemistry v.s. Laboratory Chemistry

We can best illustrate the difference between lab. scale and industrial operations using examples.Consider the hydration of ethene (ethylene) to give ethyl acohol.

Lab. procedure1. Bubble ethene into 98% H2SO4.2. Dilute and warm to hydrolyse the sulphate ester3. Distil to separate the ethanol.

Industrial processA stream of Ethene is mixed with steam at 325°C and 1000psiand passed over a solid catalyst consisting of phosphoric acidabsorbed on diatomaceous earth.The process is run continuously in a flow reactor.

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Phenol Production

Cl

ClO OH

+ Cl2 + HCl

+ NaOH

Na+-

+ HCl + NaCl

Lab. TypeProcess

97% yield overall but it converts expensive Cl2 into worthless NaClCl

OH

+ HCl + 1/2 O2 + H2O350 ºC

Cat.

300 ºC Cat.

Industrial TypeProcess

< 10% per passbut recycle is possible

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Most Lab. Procedures are:1. Liquid phase batch type processes2. Conducted at low temperature and pressure3. Rarely use flow reactors.

Yield is a familiar concept in Lab. Work but other terms are oftenused in industry.

The most important are Conversion and Selectivity or Efficiency

Conversion is a % = amount converted / amount charged (put in)

Efficiency or Selectivity is a % = amount converted to desired prod. /amount converted

Yield can be ambiguous when applied to industrial processeswith recycling streams.

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Conversion and Efficiency of the Hydration of Ethene

6.00 moles of ethene and 10 moles of water are fed into areactor . The reactor effleunt contained:0.244 moles of ethanol,9.750 moles of water and5.748 moles of ethene.

The conversion of ethene is 100(6.00 – 5.748) /6.00 = 4.2%

The efficiency of the process, or the selectivity of the catalyst, is100(0.244)/(6.00-5.748) = 97%

The yield of ethanol based upon ethene converted is100(0.244)/(6.00-5.748) = 97%

The yield of ethanol based upon ethene charged (put in) is100(0.244) /6.00 = 4.07%Yield is not used as it may be ambiguous.

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Products

Reactants

E(act)

E(act) Cat.

Effect of a Catalyst

N.B. A catalyst can reduce the activation energy of a reactionand thus speed the rate at which the reaction reaches equilibrium.A catalyst cannot alter the ratio of reactants / products presentat equilibrium.

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Two types of process can be considered.

Batch Process

Add reactants + Cat.Monitor extent of reaction,stop the reaction and empty reactor.Reactants are processed in Batch.The catalyst may be homogeneous or heterogeneous

Reactantsand Cat.

R in

P out

Hetero cat.

Flow or Continuous Process

A continuous flow reactoris favoured if it is possibleto use one.The catalyst must be heterogeneous if it is to remain in the reactor.

R in

P out

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A Batch Reactor is used when:1.The starter is of variable composition.(e.g. margarine production oil +H2 → Solid fat)

2.The reaction difficult to control. (polmerization reactions which have a chainmechanism)

Continuous or Flow Reactor is used when:1. The reaction is reproducible2. The reaction is easy to control.

(The hydration of ethene can be carried outin a flow reactor).

Choice of Reactor Type

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Homogeneous v.s Hetergenous Catalysis

Homogeneous catalysts have:1. Higher actity and less is required2. More even reaction across the reactor.3. A more difficult separation of Product/Catalyst.4 A reaction mechanism that can be studied in detail.

Heterogeneous catalysts have:1. Limited contact with the reactants.2. No problem separating Product/Catalyst3. More empirical methods since the reaction mechanism is difficult

to study.4. Possibile difficulties when reactions have bimolecular

mechanisms.

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Interconnected Reactors are a Feature of Large Chemical Plant.

Phosphate Rock Froth floatation will be used to illustrate some ofthe general features. Two interlinked floatation units.

R

F PQ

W

FL1 FL2

Stream %wt (P2O5 on dry basis)F=5% W=1%R=10%Q=12%P=20%

If all streams are 30% SolidCalc. P & W if F = 100 tons/Hr.

Use Material Balance i.e. what goesinto a box (real or imaginary) mustcome out.

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Material Balance

Total Phosphate Balance

This will work because there is phosphate is in all streamsUsing F, P and W and what goes in must come out.

F= P + W and if P = x100= x + 100-x

Convert this to solids100*0.3=x*0.3 + (100-x)0.3

Converting to P2O5 gives5*0.3 = x*0.3*0.2 + (100-x)0.3 *0.011.5 = 0.06x + 0.3 – 0.003xx = 21.06 tons/Hr.P = 21.06 W= 78.95

Box 1 F + R = Q+WBox 2 Q = P + RTotal F = P + W

F = 100 tons/hrP = 21.05W = 78.95Q = 105.25R = 84.2

N.B. Recycle streams are much largerthan product stream

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Crystallization of NaHCO3

Crystallization of NaHCO3 from a 15% solution.Calculate the rate of H2O removal per hour andCalculate crystalline NaHCO3 production per hour.

evapororator

crystallizer

Feed1000kg/hr

H2O

Crystals/kg 0.98 NaHCO30.02 H2O

Recycle 30%

Notice that all NaHCO3 leaves in crystals(1000 kgF * 0.15) / 0.98 =153.1 kg crystals / hr.

H2O / hr = F – crystals = 1000 – 153.1 = 846.9 kg H2O / hr

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Chlor-Alkali IndustryOld chemical reactions and the evolution of early inorganicsprincipally Soda (Na2CO3) and Caustic Soda (NaOH) ledto the development of the chlor-alkali industry.Soda and Caustic had the following inter-related uses:

(1) Soap making required alkali (NaOH)NaOH + RCOOH = NaR (Soap) + H2O (fat saponification)

(2) Glass was made from Silica & Soda (Soda Glass i.e. soft glass)(3) Alkali could be made from soda using a cheaper base and the

insolubility of CaCO3Na2CO3 + Ca(OH)2 = 2NaOH + CaCO3↓

Soda occurred naturally but artificial production started in Francedue to war. In 1783 a prize was promised to leBlanc (2400 livres)for a suitable process (leBlanc was cheated and died in poorhouse).leBlanc processNaCl + H2SO4 = Na2SO4 (saltcake)+ 2HCl (fumes)Na2SO4+CaCO3+ 2C→ Na2CO3+CaS + 2CO2

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The leBlanc process was appalling, a terrible source of pollutionand the Alkali Inspectorate was setup in the UK in 1863.This was the first emission control legislation.

You can get some idea of how bad this was from a letter in theLiverpool Mercury 5th Oct 1827“Muspratt’s works pour out such volumes of sulpherous smoke as todarken the whole atmosphere in the neighbourhood so much that thechurch of St. Martin in the fields now erecting can not be seen from thehouses at about 100 yds. distance, the stones of which are alreadyturned a dark colour from the same cause.The scent is almost insufferable….”

The leBlanc process was last operated in the 1920s in the UK.

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Solvay ProcessNH3 + H2O+ CO2 = NH4HCO3NaCl+ NH4HCO3 = NaHCO3↓+ NH4Cl2NaHCO3 = Na2CO3 + H2O+CO2NH3 is recovered2NH4Cl+Ca(OH)2 = CaCl2 (by product)+2NH3+2H2O

CaCO3 (limestone) = CaO +CO2CaO + H2O→Ca(OH)2

Notice there are no HCl fumes here.

The Solvay Process was a huge improvement. This is based on the lower solubility of NaHCO3 relative to NH4HCO3in H2O

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Electrolylic processes started in early 1900s and became dominantin alkali production in 1930s

Electrolytic routes to NaOHThese all rely on electrolysis of brine

Na+ + Cl - = Na(calthode) + ½ Cl2↑ (anode)Na + H2O→ NaOH + ½H2↑

Overall reactionNaCl / H2O = NaOH + ½H2 + ½Cl2

Two types of cells are used1. Mercury electrode cells2. Diaphragm and membrane cells

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Cathode (Hg) reactionNa+ + e = Na + Hg = Na/Hg (amalgam)

Outside cell (denuder)Na/Hg + H2O = NaOH + 1/2H2

AnodeCl- - e = 1/2Cl2

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The mercury or long cell (up to 50 feet long)

The cathode is flowing Hgand the anode is Ti coated steel.

Hg falls into denuderwhere it reacts with H2O.To keep the Hg flowingan Archimedean screwpump is used.

Na dissolves in HgTo give a liquid amalgamup to 3% (wt.) at R.T.

1966-225,000Amp 1976-400,000AmpNaOH→ 40% (wt)However Hg is toxic andbrine<20-40ppm Ca<1ppm MgNo new Hg cellsare being constructed.

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In the diaphragm cell the anode and cathode are separated by anasbestos diaphragm.

Anode Reaction : Na+ Cl- ions in equilibriumCl- loses e- = ½Cl2↑Na+ containing solution flowsthrough diaphragm to cathode.

Cathode Reaction2H2O +2e=H2+2OH-

Hydraulic pressure usedto prevent OH- moving to Cl2 sectionThus NaOH builds up inCathode compartment. Currents up to 120,000Aare possible.NaOH conc. 15% max.

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Membrane cellsThe membrane replaces the diaphragm. The membrane is a very thincation exchanger allowing Na+ ions only to move through.To withstand the corrosive conditions in the cell the membranemade from Nafion as follows (Nafion is a Dupont trademark).

(CF2CF2)n-CF-(CF2CF2)n-⎥O⎥CF2CF ⎯CF3⎥O⎥CF2CF2SO3

- Na+

Similar to a polystyrene cation resin This is a cation exchanger and will allowNa+ anode → cathode and inhibitsOH- → anode there is no need forhydraulic pressure

Much better NaOH is provided by thisprocess as there is far better control ofNa+ ions.NaOH 30-35% (only a few ppm NaX)Typical cells 100,000A 1000kg Cl22400 kw/tonne Cl2

Uses of Cl2 vinyl chloride production, solvents CH2Cl2, CHCl3,propylene oxide production Hg 36% chloromethanes Dia 49%,inorganic chemicals membrane 10% and paper production.