Evaporation occurs when liquid molecules escape from surface into gas phase. Only fraction of liquid molecules have enough energy to escape. Evaporation reduces liquid temperature through evaporative cooling. Process continues until equilibrium between evaporation and condensation
Ultrafiltration separates solutes through semipermeable membranes using pressure or concentration gradients. Retentate contains high molecular weight solids, permeate contains low molecular weight solutes. Process works in cross-flow or dead-end mode
Ernest Solvay developed modern ammonia-soda process in 1860s. Process replaced Leblanc method, which was more expensive and polluting. Worldwide soda ash production reached 42 million tonnes in 2005
Chemical engineers convert raw materials into products using chemistry and basic sciences. Term appeared in print in 1839, suggesting mechanical engineering knowledge in chemical industry. Edward Charles Howard (1774-1816) considered first eminent chemical engineer
Smelting extracts metals from ores using heat and reducing agents. Carbon monoxide is commonly used as reducing agent. Sulfide ores are roasted before smelting to convert to oxides. Fluxes like limestone remove impurities from ore
Hydrogenation is the addition of hydrogen to compounds using catalysts. Process typically involves adding hydrogen pairs to alkenes. Requires catalysts like nickel, palladium or platinum for usable reactions. Hydrogenation reduces double and triple bonds in hydrocarbons