(1) The raw materials for today's dyes are mainly aromatic hydrocarbons: benzene, toluene , naphthalene, anthracene, pyrene, and others.(2) Toxic chemicals such as benzene, toluene and methyl benzene were included in the list.(3) In a second method, toluene is mixed with nitric acid and oxidized to produce benzoic acid.(4) In combination with nitric acid, toluene gives trinitrotoluene.(5) The powdered bark can also be treated with solvents, such as toluene , or amyl alcohol to extract the quinine.
