METHOD OF PREPARING OLEFINIC C-C HYDROCARBONS Russian patent published in 1999 - IPC

FIELD: chemical industry. SUBSTANCE: method of preparing olefinic C₃-C₅ hydrocarbons by dehydrogenation of corresponding paraffinic hydrocarbons is carried out in reactor-regenerator system containing fluidized alumochromium catalyst bed and comprises recuperation of heat of the resulting contact gas and regeneration gas and isolation therefrom of spent catalyst recycled to system. Isolation of spent catalyst and its recycle are carried out in dry form at 30-450 C. Catalyst is recycled to reactor and/or regenerator to height which constitutes 15-85% of height of fluidized catalyst bed. EFFECT: increased yield of the desired product such as olefins, lower consumption of catalyst and improved ecology of the process. 4 ex, 2 tbl