Green manufacturing process of chromium compounds

Chromium compounds are important basic chemicals essential to many industries. In the traditional process for manufacturing these compounds, the utilization efficiency of resources and energy is quite low. Large amounts of chromium-containing toxic solid wastes and exhaust gas are discharged, resulting in serious pollution problems. A green manufacturing process of chromium compounds has been developed by the Institute of Process Engineering, Chinese Academy of Sciences in Beijing, China. With the design objective of eliminating pollution at the source, this green process achieves higher resource utilization efficiency and zero emissions of chromium-containing waste residue by alteration of process chemistry, change of reactor and operation, regeneration and recycle of reaction media, and comprehensive use of resources. By use of the green process, a demonstration plant with an annual production capability of 10,000 tons has been built and operated in Henan Province, China. The green process exhibits a promising prospect for the industrial production of chromium compounds. (c) 2004 American Institute of Chemical Engineers Environ Prog,