O_2和SO_2对稀土氧硫化物上羰基硫水解反应的影响

Effect of O_2 and SO_2 on Hydrolysis of Carbonyl Sulfide over Rare Earth Oxysulfides

研究了O_2和SO_2对氧硫化镧和氧硫化钕催化剂上COS水解反应的影响.结果表明,当φ(O_2)<2.0%时,稀土氧硫化物显示出了良好的抗氧性能,而且温度增加有利于提高催化剂的抗氧能力.一定量的SO_2会导致催化剂活性的降低,但这种失活是可逆的,可能是由于SO_2和COS在催化剂表面的竞争吸附所致.

The effect of the presence of O2 and SO2 in the feed on the COS hydrolysis was studied over lanthanum oxysulfide and neodymium oxysulfide. When O2 concentration was below 2.0%, the activity was not affected and at the O2 concentration of 2.0% a conversion of over 90% could be obtained over both catalysts when the temperature was over 150 ℃. Thus, the rare earth oxysulfide catalysts showed to be obviously superior to the traditional Al2O3 or TiO2based catalysts with respect to the resistance to the poisoning of oxygen. The presence SO2 would cause the reversible poison. The reversible deactivation of catalyst may be related to the competitive adsorption between SO2 and COS on the catalyst surface.