柠檬酸对Co/AC催化剂氨合成性能的影响

Co/AC催化剂中钴的分散度低，催化剂低温活性差，利用柠檬酸改性的方法提高钴的分散度，改善钴基氨合成催化剂的低温活性。活性测试结果表明，随着柠檬酸含量的增加，催化剂活性〖JP3〗先增加后降低,柠檬酸质量分数12%(以活性炭的质量为基准)的催化剂催化活性最佳。在425 ℃、10 MPa和10 000 h^-1条件下，用质量分数12%的柠檬酸处理六水硝酸钴所得的催化剂活性约是未处理的150%，柠檬酸处理前驱体使催化剂活性显著提高。柠檬酸对Co/AC催化剂活性的影响主要是通过改善钴的分散度起作用。

Effects of citric acid on the performance of Co/AC catalyst for ammonia synthesis

Co/AC catalysts had low cobalt dispersion and poor catalytic activity in low temperature.The modification method of citric acid for Co/AC catalyst were carried out in order to enhance the dispersion of cobalt and catalyst activity in low temperature.The results of activity evaluation showed that the activity of the catalyst increased first and then declined with the increase of the content of citric acid.Compared with the untreated catalyst,the activity of the catalyst treated with 12wt% citric acid was increased 150% under the condition of 425 ℃,10 MPa and 10 000 h^-1.The activity of the catalyst was remarkably enhanced by treating the precursor with citric acid.Citric acid had the influence on the activity of Co/AC catalyst mainly by improving cobalt dispersion.