Good Luck on the Exam

National University –SUDA Faculty of Clinical and Industrial Pharmacy

Second Year (Batch-PA-13)-Semester Four

Professional Skills-2- Laboratory Skills-1

(PA-SKILL-221)

Course Coordinator: Us. Ghada Mustafa Eltayeb, Phone Number (00249-912242444 / 00249-990997710).

Assistant Coordinator: Us. Maria M. Elamin Hamid,

Phone Number (00249-913714903 / 00966567560185)

Ghada

FILTRATION

Practical, No-6

Objectives

1. To identify filtration 2. To determine the factors affecting in rate of filtration 3. To classify the filtration 4. Recognize the mechanism of filtration 5. To know the advantages and dis advantages of each type of

filtration

By the end of this lesson the student is expected ………..

Factors affecting Rate of Filtration

Thickness of the Filter medium (L, m)

Viscosity of the Fluid (μ, Pa s)

Pressure difference (∆P, Pa)

Area (A, m2)

The chosen filtration process must remove the contaminants from the product

• At an acceptably fast rate

• Economically

Aulton’s Pharmaceutics

Methods used to increase the Rate of Filtration

• Increase the area available for

filtration

Increase the pressure difference across

the filter cake

Decrease the viscosity of the filtrate

Decrease the thickness of the filter

cake

Increase the permeability of the cake

Cooper and Gunn’s Tutorial pharmacy

Filter Aids:

Filtration is the separation of solids from liquids by forcing the liquid to flow

through a porous medium and depositing the solids on the medium. A filter aid

(finely divided material added to the liquid to be filtered) helps control flow and

solids removal. an agent consisting of solid particles (as of diatomite) that improves

filtering efficiency (as by increasing the permeability of the filter cake) and that is

either added to the suspension to be filtered or placed on the filter as a layer

through which the liquid must pass.

Classification of Filtration (machinery)

There are Four types of Filtration based on their external force namely-

Gravity Filtration

Vacuum Filtration

Centrifuge filtration

Pressure Filtration

Filtration

Gravity Filtration:

Gravity filtration is the method of choice to remove solid impurities from an organic liquid. The impurity can be a

drying agent or an undesired side product or leftover reactant. It can be used to collect solid product.

A filtration procedure called "hot gravity filtration" is used to separate insoluble impurities from a

hot solution. Hot filtrations require fluted filter paper and careful attention to the procedure to keep the apparatus

warm but covered so that solvent does not evaporate.

To perform a standard gravity filtration, first select the size of filter paper that, when folded, will be a

few millimeters below the rim of your stemmed funnel. Fold the paper into a cone by first folding it in half, and

then in half again, as shown.

Next, support the glass funnel in a ring or place it in the neck of an Erlenmeyer flask. Wet the filter paper

with a few milliliters of the solvent to be used in the following procedure. Wetting the paper holds it in place

against the glass funnel. Pour the mixture to be filtered through the funnel, in portions if necessary.

Vacuum Filtration:

Vacuum filtration is used primarily to collect a desired solid, for instance, the collection of crystals in a

recrystallization procedure. Vacuum filtration uses a Buchner funnel and a side-arm flask. Vacuum filtration is

faster than gravity filtration. Do not use vacuum filtration to filter a solid from a liquid if it is the liquid that you

want, and if the liquid is low boiling.

To perform a vacuum filtration, clamp the flask securely to a ring stand.

Add a Buchner funnel with a rubber funnel adaptor.

Connect the side arm flask to a vacuum source.

Always use thick-walled tubing , since tubing

Will collapse under reduced pressure.

Wet the paper with a small amount of the solvent to be used in the

filtration. Make sure the paper is secure on the filter, that air is

being drawn through the paper, all of your apparatus is securely clamped.

Pour the mixture to be filtered onto the filter paper. The vacuum

should rapidly pull the liquid through the funnel. If this happens,

start over and carefully pour portions of the solution onto the

very center of the paper.

Carefully disconnect the rubber tubing.

Remove the filter paper and the collected solid that is on it.

Usually you will need to set the product on a watch glass

and let it air dry for a while.

Centrifuge filters:

Centrifugal filters are used in laboratory settings to manipulate peptides, proteins, oligonucleotides, DNA, and RNA

samples. The devices successfully clean up labeling and PCR reactions, isolate specific sections, buffer exchange,

clarify samples, and remove particulates. The centrifugal filters will meet concentration, purification, separation and

desalting procedure requirements.

Pressure Filtration:

Pressure type filter holders can be used for ultra cleaning or sterilizing liquids and gases. Advantege holders have

been designed to maximize flow rates and to minimize holder resistance and can be used in either batch or continuous

filtration procedures.

Pressure filters may be grouped as shown in the tree to the right.

The sizes for standard equipment are as follows:-

Filterpress up to 1000 m2 and 20 m3 cake.

Horizontal Plate Filter up to 60 m2 and 4 m3 cake capacity

Vertical Leaf Filter up to 100 m2 and 7 m3 cake capacity in vertical pressure vessels and up to 300 m2 and 20

m3 cake capacity in horizontal vessels.

Nutsche Filter up to 16 m2 and 8 m3 cake capacity.

Automatic Filter up to 120 m2.

Candle Filter up to 120 m2.

Pneumatic Filter up to 90 m2

Application… Pharmaceutical industry :

Enzymes, amino acids, antibiotics, pharmaceutical intermediates, bulk drugs, medicine, blood products, antibiotics calcium phytate, Chinese inositol, growth derived sand, organic phosphorus, glucoamylase.

Chemical industry:

Dyes, pesticides, silicic acid, glycerin, white carbon, busy, sodium carbonate, additives, basic chemicals, chemical filler, pigment, white alumina, manganese, caustic soda, soda ash, alkali salts mud, saponin, graphite.

Food industry :

Wine filter press, yeast, fruit juice filter press, edible oil, vegetable oil, soy sauce, sugar mills, rice wine, white wine, fruit juices, soft drinks, beer, yeast, citric acid, vegetable protein, plant density sweetener, glucose.

Environmental Engineering :

Chemical waste water, wastewater filter press, mining wastewater filter press, domestic wastewater, waste water, waste steel, waste removal, leather waste water, ports silt, mud, salt mud wastewater.

Clay industry :

Kaolin, bentonite, activated clay, clay, electronic ceramics clay.

ADVANTAGES…

Construction of the filter press is simple and variety of materials can be used.

It is provided a large filtering area in the relatively small floor space.

The sturdy construction permits the use of the considerable pressure difference.

Efficient washing of the cake is possible.

It produces dry cake in the form of slab.

DISADVANTAGES…

inefficient and the cake is

It is a batch filter so there is a good deal of down time which is non productive.

The filter press is an expensive filter.

Operation is critical as the frames should be full other wise the washing is difficult to remove.

The filter press is used for the slurries containing less than 5% solids.

For more informations please watch video P-7