colorless orthogonal edges or flake - like cylinder body. A small amount of water into the presence of liquid. With water dissolved by any proportion. Water formed azeotropic mixture (21.76% water). Difficult dehydration. Degeneration system for alcohol, spices, fruit sperm and also used as paint solvents. Sulfuric acid from isobutene after esterification and hydrolysis in the system. Also available ion exchange resin or sulfuric acid as the catalyst directly from iso-type system in which hydration.