Comparison between Comparison between filtration and centrifugation filtration and centrifugation

processprocess

Course: Bio-separationInstructor: Dr Nguyen Van Toan

(PhD)Presented by Group 7

GROUP’S MEMBERSGROUP’S MEMBERS

Pham Anh Vu BTIU08

ContentContentI. Introduction to Liquid-Solid Separation

techniquesII. Two common techniques1. Filtrationa. Fundamental of filtrationb. Types of filtrations2. Centrifugationa. Fundamental of centrifugationb. Types of centrifugations

III. Comparison between Filtration and Centrifugation

IV. Discussion

WHAT IS HE DOING ???

I. Introduction to Liquid-Solid I. Introduction to Liquid-Solid SeparationSeparation

Solid-Liquid Separation is a major unit operation that exists in almost every industrial bioseparation.

It is the removal of insoluble solids from the fermentation beer.

The concentration and size of these insolubles are different

We have two common techniques: filtration and centrifugation

II. Two common techniquesII. Two common techniques11. Filtration. Filtrationa. Fundamentala. Fundamental

- Filtration is a technique used either to remove impurities from an organic solution or to isolate an organic solid

oversize particles in the feed cannot

pass through the lattice structure

of the filter, while fluid and small particles pass through,

becoming filtrate

b. Types of Filtrationb. Types of Filtration

The two types of filtration commonly used in organic chemistry laboratories are gravity filtration and vacuum or suction filtration.

Gravity FiltrationThe method of choice to remove solid

impurities from an organic liquidThe "impurity" can be a drying agent or an

undesired side product or leftover reactantFiltration separates solids from a liquid by

forcing the liquid through a solid support or inter-medium.

Gravity filtration can be used to collect solid product, although generally vacuum filtration is used for this purpose because it is faster.

Procedure for standard gravity filtration

1)Select and fold the filter paper

1 2

2) Filter the solution

Vacuum filtrations- Is used to collect a desired solid- Particle size: greater than 10 µm,

yeast, mold, animal or plant cells. - EX: the collection of crystals in a re-

crystallization procedure.

- The solvent or solution and air is forced through the filter paper by the application of reduced pressure

- Faster than gravity filtration

The reduced pressure requires special equipments

Buchner or Hirsch funnel Heavy-walled, side arm filtering flask Rubber adaptor or stopper to seal the

funnel to the flask when under vacuum Vacuum source

Recommendation of using Recommendation of using filtrationfiltrationGravity filtrationThe mixture is hot

(above room temperature)

The liquid is saturated with one or more reagents

The solvent is very volatile (chloroform, alcohols, ethers).

Vacuum filtrationThe conditions

where gravity filtration is recommended are NOT present

A quick separation is required

Some others types of Some others types of FiltrationFiltration

Microfiltration is a filtration process which removes contaminants from a fluid (liquid & gas) by passage through a microporous membrane. Use pressure as a means of forcing water to go from low pressure to high pressure. ◦ Particle size: 0.1 - 10 µm, bacterial and yeast

cells.

Ultrafiltration is a variety of membrane filtration in which hydrostatic pressure forces a liquid against a semipermeable membrane.

- Suspended solids and solutes of high molecular weight are retained, - Water and low molecular weight solutes pass through the membrane

Particle size: 10-200 Å, Cell debris, macromolecules

II. CentrifugationII. Centrifugationa. Fundamental

- Centrifugation is a process that involves the use of the centrifugal force for the separation of mixtures- Centrifugation utilizes the density difference between the solids and the surrounding fluid. - More-dense components of the mixture migrate away from the axis of the centrifuge- Less-dense components of the mixture migrate towards the axis

Supernatant liquid

Precipitate (pellet)

2. Types of centrifugation2. Types of centrifugation

a. Differential centrifugation- Based on the size of the particles- Commonly used in simple pelleting

and in obtaining partially-pure preparation of subcellular organelles and macromolecules

- Ex: For the study of subcellular organelles, tissue or cells are first disrupted to release their internal contents. (Figure below)

b. Density gradient centrifugation- To purify subcellular organelles

and macromolecules- Density gradient separation can

be classified into two categories. + Rate-zonal (size) separation. + Isopycnic (density) separation.

+ Rate-zonal (size) separation. Rate-zonal separation takes advantage of particle size and mass instead of particle density for sedimentation

Ex: Antibody classes all have very similar densities, but different masses.

-> separation based on mass will separate the different classes, whereas separation based on density will not be able to resolve these antibody classes.

Isopycnic separationA particle of a particular density

will sink during centrifugation until a position is reached where the density of the surrounding solution is exactly the same as the density of the particle

EX: separation of nucleic acids in a CsCl gradient

III. III. Comparison between Filtration and Centrifugation Comparison between Filtration and Centrifugation processesprocesses

SIMILARITIES

Chemical Unit

Operation

Separated Objects

Suspended solids from the fluid phage

Separate Water by using Force

DifferencesDifferencesFiltration Centrifugation

1 Gravity or vacuum Centrifugal force

2 Simple More complicated

3 Insolubles are dilute, large, and rigid

size ranges from microorganisms (d=1µm) to insoluble nutrients(d=1mm)

4 Cheaper Expensive

5 Lower solid concentrate produced by filtration

Higher solid concentrate produced by filtration

6 Lower concentrated suspension

More concentrated suspension.

7 Filtration produces a relatively dry cake

Not produce dry cake

SummarySummary

DISCUSSION

In 2007, At An Binh I Primary in Can Tho City, there are 18 pupils were poisoned after drinking water which are

purified at the school

3 Hours

WHY???

REFERENCESREFERENCES D. Khanh. 2007. Ngo doc nuoc. [Internet]. [Cited: Oct

8, 2010]. Available from: http://vietbao.vn/Suc-khoe/Uong-nuoc-loc-18-hoc-sinh-nhap-vien/62187918/248/

Cole-Pamer. Technological Library. Basic of Centrifugation. [Internet]. [Cited: Oct 8, 2010]. Available from: http://www.coleparmer.com/techinfo/techinfo.asp?htmlfile=basic-centrifugation.htm&ID=30

GEA Filtration. Cross-flow membrane filtration systems and replacement membranes . [Internet]. [Cited: Oct 8, 2010]. Available from: http://www.geafiltration.com/index.asp

Thank you for your kindly listening!!!