The influence of the textural and acidic properties of γ-Al2O3, (γ+χ)-Al2O3, and α-Al2O3on the catalytic activity, selectivity, and stability of direct H2S oxidation has been studied. A comparison of the H2S-to-S conversion effectiveness of aluminas with their acidic properties (identified by Fourier transform infrared spectroscopy and temperature programmed desorption of NH3) shows that H2S adsorption occurs predominantly on weak Lewis acid sites (LAS). γ-Alumina samples containing a χ-phase and/or modified Mg2+ ions have a greater concentration of weak LAS and exhibit greater catalytic activity. When alumina is treated with a sulfuric acid solution, strong LAS appear and the number of LAS decreases significantly. Modification of alumina with hydrochloric acid has a limited effect on LAS strength. Weak LAS are retained and double in number compared to that present in the unmodified alumina, but the treated sample has Al﹣Cl bonds. Alumina samples modified by sulfate and chloride anions exhibit poor catalytic activity in H2S oxidation.%考察了γ-Al2O3,(γ+χ)-Al2O3和α-Al2O3的结构性质和酸性对其催化H2S直接氧化反应性能(活性、选择性和稳定性)的影响.采用红外光谱(FTIR)与氨-程序升温脱附(NH3-TPD)方法对氧化铝作用下H2S转化为S的反应性能与其酸性进行了比较.结果显示,H2S吸附主要发生在弱Lewis酸位.含有χ相和/或Mg2+修饰的γ-Al2O3样品具有更高浓度的弱Lewis酸位,并表现出更高的催化活性.当氧化铝样品用硫酸溶液处理后,表现出强Lewis酸位性质,且Lewis酸位点数量显著下降.而当用HCl对氧化铝进行修饰时,其对Lewis酸位强度的影响很小,保持着弱Lewis酸位的性质,且其Lewis酸位数量与未修饰的样品相比增加了二倍,但处理过的样品中含有Al?Cl键.用硫酸盐和氯离子修饰过的氧化铝样品在H2S氧化反应中的催化性能均较低.
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