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采用溶胶 -凝胶法 ,制备了不同钴含量的钴钼超细粒子氧化物 ,将其与 K2 CO3干混后进行硫化 .使用 X-射线衍射 (XRD)和扩展 X光吸收精细结构 (EXAFS)对样品进行结构表征 ,同时测试硫化态样品的 CO加氢合成低碳混合醇性能 .结构表征结果表明 ,不含钴的氧化态样品 ,主要以颗粒度较大的 Mo O2 物种存在 ;添加钴后 ,样品粒子的颗粒度大幅度降低 ,钴钼组分主要以 Co Mo O3物种的形式存在 ,当钴含量增加时 ,Co Mo O3的晶形趋于改善 .硫化态样品中钼以类似于 Mo S2 物种的形式存在 ,但粒子尺寸较小 .同时 ,体系中还存在 Co- Mo- S和Co9S8物种 .XRD和 EXAFS结果表明 ,适量钴的添加 ,有利于样品的硫化 .活性测试表明 ,钴的加入 ,明显促进了超细粒子催化剂合成醇的活性及 C2 +醇选择性的提高 ,其中 Co/Mo比为 1 .0 0的样品 ,活性最好 ,产物中 C2 +醇的含量也最高 .结合结构表征结果 ,认为钴是以协同作用的方式参与反应 .
Cobalt-molybdenum ultrafine particle oxides with different cobalt contents were prepared by sol-gel method and then mixed with K2 CO3 for sulfidation.Using X-ray diffraction (XRD) and extended X-ray absorption fine structure (EXAFS) The structure of the sample was characterized and the properties of low-carbon mixed alcohol (CO) hydrogenated by CO hydrogenation in the sulfided samples were also tested.The results of structural characterization showed that the cobalt-free oxidized samples mainly existed as Mo O2 species with larger particle size, , The grain size of the sample particles is greatly reduced, the cobalt and molybdenum components are mainly in the form of Co Mo O 3 species, and the shape of the Co Mo O 3 crystal tends to improve as the cobalt content increases. The molybdenum content in the sulfide sample is similar to that of the Mo S2 species But the size of the particles is small.At the same time, there are Co-Mo-S and Co9S8 species in the system.XRD and EXAFS results show that the addition of appropriate amount of cobalt is conducive to the vulcanization of the sample.The activity tests show that the addition of cobalt, The activity of synthesizing alcohol and the selectivity of C2 + alcohol were obviously promoted by ultrafine particle catalyst. The sample with Co / Mo ratio of 1.0 was the best and the content of C2 + alcohol in the product was the highest. As a result, cobalt is considered In a synergistic way to participate in the reaction.