钾促进型Co-Mo系耐硫变换催化剂性能研究  

Studies on Catalytic Performance of Potassium-Promoted Co-Mo Based Sulfur-Tolerant Shift Catalyst

作　　者：纵秋云[1] 余汉涛[1] 郭建学[1] 张新堂[1] 孙海燕[1] 

机构地区：[1]齐鲁石化公司研究院,山东淄博255400

出　　处：《催化学报》2002年第6期521-524,共4页

摘　　要：采用常压微反色谱评价装置 ,TPR ,XRD和SEM等技术 ,考察了钾对Co Mo系耐硫变换催化剂活性及抗水合性能的影响 .结果表明 :在原料气中H2 S含量大于 0 0 5 %的条件下 ,钾的加入量存在一个最佳范围 ;在原料气中H2 S含量小于 0 0 5 %的条件下 ,增加催化剂中的钾含量 ,可以提高催化剂“捕硫”的能力 ,从而能提高催化剂耐“低硫”的能力 .在高于露点温度 18～2 0℃的苛刻条件下 ,钾的加入能促进γ Al2 O3 载体与水蒸气的水合反应 ,使催化剂的抗水合性变差 .还探讨了催化剂发生水合反应后对其活性的影响 .结果表明 ,γ Al2 O3 载体发生水合相变后能引起催化剂活性大幅度下降 ,而钾的加入加剧了催化剂发生水合反应的程度 ,导致其催化活性进一步下降 .The catalytic performance of potassium-promoted Co-Mo based catalyst for water-gas shift reaction was investigated by using micro-reactor chromatograph, temperature-programmed reduction, X-ray diffraction and scanning electron microscope techniques. The results showed that when phi (H2S) > 0.05% in feed gas, the catalyst activity at various temperatures can be obviously increased with potassium contents if w(K2O)less than or equal to6.0%, the catalyst activity was hardly varied if w (K2O) = 8.0% similar to 10.0%, and the catalyst activity decreases with the increase of potassium content if w(K2O)greater than or equal to12.0%, showing that there is an optimum range for potassium content. When phi(H2S)<0.05% in feed gas, increasing the potassium content in the catalyst, the ability of the catalyst to snatch sulfur can be enhanced under lower sulfur-level in feed gas, so that the catalyst function of tolerating lower H2S contents can be increased. The ability of various catalyst samples to react with water steam was, studied under the condition of exceeding the dew point temperature by 18similar to20 degreesC. It was found that all the samples with different K2O contents before hydration have gamma-Al2O3 phase, showing that the potassium is highly dispersed on the support surface. After the experiment of hydration, the structural property of the samples was changed. The gamma-Al2O3 phase virtually disappeared and a lot of new hydrated AlOOH phase grew, showing that the hydration of gamma-Al2O3 support has occurred during the experiment. With the increase of potassium content, the content of AlOOH phase was also increased, showing that the potassium promoted the hydration between gamma- Al2O3 support and water steam, and resulting in that the anti-hydration of the catalyst was weakened. The catalyst activity after hydration was reduced because of the hydration of gamma-Al2O3 support, and the hydration extent of the catalyst was intensified by potassium so that the catalyst activity was reduced obviously.

关 键 词：氧化钾 氧化钴 氧化钼 耐硫变换催化剂 低硫活性 抗水合性 催化活性 

分 类 号：O643.3[理学—物理化学]