钴源对费托合成Co@AC催化剂的影响

Fischer Tropsch Synthesis:Precursor Pair Co@AC Effect of Catalyst

以硝酸钴、醋酸钴和氯化钴三种钴源为前驱体,以自制的活性炭(AC)为载体,利用浸渍法制备了钴催化剂,使用X射线衍射和程序升温还原技术对催化剂进行了表征,并进行了费托合成反应测试,分析了前驱体对催化剂构效关系的影响。结果表明,虽然以氯化钴为前驱体的催化剂上出现高活性hcp晶相,但分散度和还原度都是最差,所以活性最低;以醋酸钴为前驱体的催化剂,尽管分散度不如以硝酸钴为前驱体的催化剂,但还原度较高,所以活性最高,而且气态副产物选择性最低,这与以SiO_(2)和Al_(2)O_(3)为载体的传统钴催化剂呈现出不同的规律。

Cobalt catalysts were prepared by impregnation method with cobalt nitrate,cobalt acetate and cobalt chloride as precursors and self-made activated carbon(AC)as carrier.The catalysts were characterized by X-ray diffraction and temperature programmed reduction technology.The Fischer Tropsch synthesis reaction was tested,and the effect of precursors on the structureactivity relationship of the catalysts was analyzed.The results show that although HCP crystal phase with high activity appears on the catalyst with cobalt chloride as precursor,the dispersion and reduction degree are the worst,so the activity is the lowest;On the catalyst with cobalt acetate as precursor,although the dispersion is not as good as that with cobalt nitrate as precursor,the reduction degree is higher,so the activity is the highest and the selectivity of gaseous by-products is the lowest,which shows a different rule from the traditional cobalt catalyst with SiO_(2) and Al_(2)O_(3) as support.