Canadian Journal of Chemical Engineering, Vol.97, No.10, 2717-2726, 2019
Environmentally benign catalytic synthesis and hydro-refining of linear alkylbenzenes
The synthesis technology of linear alkylbenzenes (LABs) was studied through the preparation of an Al-SBA-15 catalyst, the optimization of alkylation conditions, and the regeneration of deactivated catalyst. The hydro-refining over the Pd/Al2O3 catalyst was carried out to remove unsaturated hydrocarbon impurities from the LAB. The results of the alkylation reactions over the Al-SBA-15 catalyst in a liquid fixed bed reactor showed that the olefin conversion remained above 98 % for time on stream of 3000 h, and the LAB selectivity was above 93 % under the following conditions: temperature of 260 degrees C; pressure of 5.0 MPa; weight hourly space velocity (WHSV) of 1.0 h(-1); and the molar ratio of benzene to olefin of 25:1. Through the burning coke regeneration, the catalytic performance of the deactivated alkylation catalyst was satisfactorily restored. The quality of the LAB synthesized through alkylation and hydro-refining was better than that of the industrial LAB produced using the hydrofluoric acid catalytic process.