Synthesis of thiophene from furan and H2S over A12O3 catalyst

Synthesis of thiophene from furan and H2S over alumina catalysts calicined at different temperatures was studied. High yield to thiophene (90.2%) was achieved from furan and hydrogen sulfide over alumina calcined at 550°C under conditions of: LHSV 0.2 h-1, n(H2S):n(furan) 10 and temperature 500°C Crystal structure and specific surface area of the catalysts were characterized by means of XRD and BET. Crystal form of the alumina transformed from γ-Al2O3 to α-Al2O3 with rising of calcinations temperature to about 1300°C and dramatically decreasing of specific surface area from 226.13 m2/g to 2.22 m2/g. Acid sites on alumina surface were determined by FTIR with pyridine adsorbed on alumina calicined at different temperatures. Reaction mechanism of furan and H2S over alumina was discussed. Lewis acid sites are active sites for thiophene synthesis from furan and hydrogen sulfide over Al2O3.