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Anonymous users2024-02-06This is a commonly used method of separation and impurity removal:
Separation, impurities.
The so-called separation is to separate the components of the mixture one by one and keep the original unchanged. The so-called removal of impurities (purification) refers to the removal of impurities, and at the same time, the purified substances shall not be changed, and new impurities shall not be introduced. If the impurities cannot be converted into the required substances, the impurities are generally converted into gases or precipitated to be removed.
List of common operations and principles of separation and impurity removal:
1. Scope of application: solid-liquid separation (solids are insoluble in filtrate).
Principle: The solid insoluble matter particles are large and cannot pass through the filter paper or filter membrane; The filtrate can pass through it smoothly.
2. Evaporation and crystallization.
Scope of application: solid-liquid separation (not suitable for solids that are easy to sublimate, decompose and hydrolyze when heated) Principle: (1) The liquid is evaporated into the environment by heating, resulting in the gradual reduction of solvent and the gradual precipitation of solid substances; (2) The boiling point of a solid is higher than the boiling point of a liquid.
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Anonymous users2024-02-05Ethylene (SO2, H2O) soda lime washing gas.
Ethane (ethylene) bromine water scrubbing.
Bromobenzene (bromine) dilute NaOH solution Separate solution.
Nitrobenzene (NO2) dilute NaOH solution Dispensing.
Toluene (phenol) NaOH solution Separate solution.
Acetaldehyde (acetic acid) saturated with Na2CO3 solution Distilled.
Ethanol (water) freshly made quicklime distilled.
Phenol (benzene) NaOH solution, CO2 separation, ethyl acetate (acetic acid), saturated Na2CO3 solution.
Ethyl bromide (ethanol) distilled water dispensing.
Soap (glycerol) table salt filtered.
Glucose (starch) semi-permeable membrane dialysis if you are satisfied, hope, thank you.
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Anonymous users2024-02-04Ethylene (SO2, H2O) soda lime washing gas.
Ethane (ethylene) bromine water scrubbing.
Bromobenzene (bromine) dilute NaOH solution Separate solution.
Nitrobenzene (NO2) dilute NaOH solution Dispensing.
Toluene (phenol) NaOH solution Separate solution.
Acetaldehyde (acetic acid) saturated with Na2CO3 solution Distilled.
Ethanol (water) freshly made quicklime distilled.
Phenol (benzene) NaOH solution, CO2 separation, ethyl acetate (acetic acid), saturated Na2CO3 solution.
Ethyl bromide (ethanol) distilled water dispensing.
Soap (glycerol) table salt filtered.
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Anonymous users2024-02-031.Ethane is mixed with ethylene.
Commons: gas, density is greater than air, insoluble in water, all flammable different points: alkanes: can not fade potassium permanganate, can not react with bromine water, olefins: can make potassium permanganate fade, can react with bromine water.
Impurity removal method: Ethylene can be removed by washing gas with bromine water.
2.Ethane is mixed with hydrogen sulfide.
Commonalities: gas, density greater than air, ethylene slightly soluble in water, hydrogen sulfide in 1: soluble in water at different points:
Ethane is an alkane, and alkane has a relatively stable structure, chemical properties are relatively stable, and it does not react with strong acids and alkalis, nor does it react with strong oxidants. Hydrogen sulfide is a weakly acidic gas, and weak acids can react with bases. At the same time, the sulfur in hydrogen sulfide is the lowest, reducible, and can react with oxidants.
Removal method: 1Wash gas with alkali; 2.Wash gas with a strong oxidizing agent 3Sulfur dioxide is mixed with ethane.
The method and principle are the same as in question 2. (Sulfur dioxide is dissolved in water at 1:40) II, converting impurities into raw substances.
For example, carbon dioxide is mixed with carbon monoxide.
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