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本文研究了CO、H_2S和C_4H_4S在Ni/γ-Al_2O_3上的化学吸附过程。实验证明,用CO在-72℃的化学吸附测定催化剂的金属表面积,是一个可行的方法。CO不吸附在被毒物掩盖的表面上。S复盖度在0.4以下,毒物S对CO在未复盖的镍表面上的吸附没有影响;复盖度超过0.4.随着复盖度增加,S明显地阻碍CO的吸附。10Vpm~(?)H_2S在H_2中的混合气体,在300—500℃下,经过约20小时的化学吸附,形成饱和吸附层,S与表面Ni原子比例为0.53,0.1%(V/V)C_4H_4S在H_2中的混合气体,在20℃经过约20小时的吸附,形成饱和吸附层。表面Ni原子与C_4H_4S分子比例为4.95。噻吩以非解离方式占据着4.95个表面Ni中心。中毒催化剂在600℃,H_2气流下经过约50小时,可以完全再生。
In this paper, the chemisorption processes of CO, H 2 S and C 4 H 4 S on Ni / γ-Al 2 O 3 were studied. Experiments show that the determination of the metal surface area of the catalyst by chemisorption of CO at -72 ° C is a viable method. CO is not adsorbed on surfaces covered with poisons. S coverage was below 0.4 and poison S had no effect on the adsorption of CO on uncovered nickel surface; the coverage exceeded 0.4. S significantly inhibited the adsorption of CO as the coverage increased. The mixed gas of 10Vpm H 2 S in H 2 formed a saturated adsorption layer by chemical adsorption at 300-500 ℃ for about 20 hours. The ratio of S to surface Ni atom was 0.53, 0.1% (V / V) C 4 H 4 S The mixed gas in H 2 was adsorbed at 20 ° C for about 20 hours to form a saturated adsorption layer. The ratio of surface Ni atom to C_4H_4S molecule is 4.95. Thiophene occupies 4.95 surface Ni centers in a non-dissociated manner. The poisoning catalyst can completely regenerate after passing through H 2 at 600 ℃ for about 50 hours.