稀土氧硫化物上的羰基硫水解反应

Hydrolysis of COS over Rare Earth Oxysulfides

研究了一种新型的羰基硫水解催化剂——稀土氧硫化物 .考察了稀土系列氧化物硫化后的水解活性 ,发现其活性顺序为 La≈ Pr≈ Nd≈ Sm >Eu>Ce>Gd≈ Ho>Dy>Er. XRD物相分析表明 ,各种稀土氧化物经水合及硫化后呈现出不同的物相变化特性 ,稀土氧硫化物是 COS水解的活性物质 .在氧硫化镧和氧硫化钕催化剂上研究了 O2 和 SO2 对羰基硫水解反应的影响 ,与传统的氧化铝基和氧化钛基水解催化剂相比 ,稀土氧硫化物显示出良好的抗氧化性能 ,而 SO2 对催化活性的影响是可逆的 .

The hydrolysis of carbonyl sulfide was studied over a novel type of rare earth oxysulfides catalyst. The order of catalytic activity of the rare earth oxysulfides was in the sequence: La≈Pr≈ Nd≈ Sm>Eu>Ce>Gd≈Ho>Dy>Er. The analysis of XRD reveals that the catalytic activity could be well related to the easiness of the sulfidation from their oxides to the corresponding oxysulfides and the rare earth oxysulfide is the active phase for the hydrolysis of COS. The effect of the presence of O 2 or SO 2 in the feed was investigated over La 2O 2S and Nd 2O 2S, respectively. At the O 2 volume fraction below 1.5% there was not any effect on the COS conversion and at 2% a COS conversion of higher than 90% was obtained at temperature over 150 ℃. The catalytic activity of COS hydrolysis decreased in the presence of SO 2 at a temperature below 300 ℃. The poisoning effect of SO 2 was reversible and may be caused by the competitive adsorption between SO 2 and COS on the surface of rare earth oxysulfides.