A professional who controls agitator tank to wash (mix) benzol, benzene, toluene, and xylene with sulfuric acid and caustic soda to remove impurities. Respnsibilities include:

• Turns valves and starts pumps to charge agitator vessel with specified amount of benzol or derivatives.
• Drains measured quantity of acid into vessel and starts agitator to mix contents for specified time.
• Stops agitator to allow acid and sludge to settle.
• Draws sample of washed product for laboratory colorimetry test to determine need for further washing.
• Opens valve, using wrench, to drain excess acid and sludge, adds caustic soda solution to neutralize remaining acid, and measures alkalinity, using standard titration test.
• Adds water, agitates mixture to wash out traces of caustic, and drains off water after contents have settled.
• Pumps washed benzol or derivatives into storage tank.
• Turns valves to admit steam to sludge kettle, solidifying sludge.
• Lifts kettle cover, using chain hoist, and removes sludge from kettle.
• May distill washed benzol in batch still.
• May remove impurities from crude ethylbenzene by adding lime and water and agitating mixture.