Solid-Liquid Extraction

Question 1

it is used to separate the desired solute constituent or
remove an undesirable solute from the solid phase

Answer 1

leaching

Question 2

4 other terms for leaching

Answer 2

1. Percolation
2. Infusion
3. Lixiviation
4. Washing

Question 3

2 applications of leaching

Answer 3

1. Biological substances
2. Inorganic materials

Question 4

4 examples of leaching agent

Answer 4

1. Water
2. Acids
3. Alkali
4. Aqueous Salt Solutions

Question 5

The solute diffuses through the mixture to the surface of the solid

Answer 5

Intraparticle diffusion

Question 6

solid-liquid stream that denser and in solid phase

Answer 6

Underflow (slurry) stream

Question 7

liquid phase that passes over the top and contains the solvent and the dissolve solute

Answer 7

Overflow stream

Question 8

Amount of solution retained with the solids (underflow)
depends upon:

Answer 8

1. Viscosity
2. Density
3. Concentration of solute in the solution

Question 9

2 types of leaching

Answer 9

1. Variable underflow
2. Constant underflow

Question 11

solution underflow is not constant (retained solution varies from stage to stage)

Answer 11

Variable underflow

Question 12

solution underflow is constant (retained solution is the same from stage to stage)

Answer 12

Constant underflow

Question 13

2 types of variable underflow

Answer 13

1. Rectangular diagram or coordinates
2. Right triangle/Triangular diagram

Question 14

the number of stages in constant underflow can be determined by

Answer 14

1. Absorption factor
2. Tiller-tour equation

Question 15

2 types of constant underlow

Answer 15

1. Constant solvent retention
2. Constant solution retention

Question 16

6 selection/design of a leaching process

Answer 16

1. Temperature
2. Choice of Solvent
3. Terminal Stream Compositions and Quantities
4. Leaching Cycle and Contact Method
5. Extractor-Sizing Calculations
6. Type of Extractor

Question 17

linked to the production capacity of the leaching plant

Answer 17

Terminal Stream Compositions and Quantities

Question 18

degree of solute removal and the concentration of the
extract stream chosen are those that maximize process
economy

Answer 18

Terminal Stream Compositions and Quantities

Question 19

depends on the size and nature of extraction

Answer 19

Leaching Cycle and Contact Method

Question 20

3 classifications of leaching equipment according to contacting method

Answer 20

1. By Percolation
2. By Dispersed-Solids Leaching
3. By Screw-Conveyors

Question 21

3 types of leaching equipment by percolation

Answer 21

1. Heap leaching
2. In situ leaching
3. Batch percolators

Question 22

this type of leaching equipment is the least expensive and applied to the ores of Cu, Au and other precious metals

Answer 22

Heap leaching

Question 23

This type of ñeaching equipment is used for halite (NaCl) and uranium extraction, and also for removal of toxic constituents from soil or groundwater

Answer 23

In situ leaching

Question 24

a type of leaching equipment which is a batch tank with a false bottom and a vat leaching

Answer 24

batch percolators

Question 25

it is series of pressure tanks operating with countercurrent solvent flow

Answer 25

diffusion/extraction battery

Question 26

4 types of continuous percolators

Answer 26

1. Bollman extractor 2. Rotocell extractor 3. Endless-belt extractor 4. Kennedy extractor