O_2,H_2S和SO_2对氧硫化镧催化性能影响的原位IR研究  

In situ IR Study of COS Hydrolysis over Lanthanum Oxysulfide:Effect of O_2,H_2S and SO_2

作　　者：金杏妹[1] 马建新[2] 周围[2] 

机构地区：[1]华东理工大学化学与分子工程学院,上海200237 [2]同济大学新能源汽车工程中心,上海200092

出　　处：《高等学校化学学报》2009年第6期1194-1198,共5页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:20173016)资助

摘　　要：对比研究了O2,H2S和SO2对La2O2S和γ-Al2O3催化剂上羰基硫(COS)水解反应的影响,与传统的氧化铝催化剂相比,氧硫化镧显示出良好的抗氧性能和一定的耐硫能力.一定量的O2或O2与H2S共存气体对La2O2S的活性几乎没有影响,但却使γ-Al2O3的活性明显下降;SO2的存在会导致两种催化剂活性有不同程度的降低,但在La2O2S上随着温度的上升其影响程度逐渐减弱.利用原位IR技术表征了La2O2S表面物种,用程序升温脱附(TPD)技术分别考察了O2,H2S,SO2单独组分及混合组分在两种催化剂上的吸附行为.研究发现,由于各组分在两种催化剂上的吸附行为不同,使COS在γ-Al2O3和La2O2S催化剂上具有不同的水解反应机理,氧硫化镧催化剂上COS水解反应遵循Rideal机理.由于SO2本身对La2O2S中的晶格S2-起输送作用,因而稀土氧硫化物催化剂具有良好的抗SO2中毒性能.The effect of the presence of O2, H2S and SO2 in the feed on the COS hydrolysis was studied comparatively over La202 S and γ-Al2O3. Compared to the traditional γ-Al2O3 catalyst, La2 O2S was observed to be obviously superiosity in resistance to the poisoning of oxygen and sulfide at higher temperature. A certain amount of O2 or H2S ＋ O2 has no effect on the activity of La2O2S, while decrease the activity of γ-Al2O3 significantly. The presence of SO2 would decrease the activity of both catalysts,but the impact on La2O2S weakens as the temperature rises. The analysis of TPD and in situ IR reveals that O2, H2S and SO2 shows different adsorption characteristics over La2O2S and γ-Al2O3. Hence, COS proceed the two catalysts via different reaction mechanisms. Spectroscopies of H2S, O2 in situ IR reveal that La2O2S hydrolyze via Eley-Rideal mechanism. The rare-La2O2 S catalyst displays an excellent poisoing performance, because SO2 can transfer the lattice S^2- inside the La2O2S.

关 键 词：羰基硫 水解 原位IR 稀土氧化物 稀土氧硫化物 程序升温脱附 

分 类 号：O643[理学—物理化学]