Ru/Ba-MgO氨合成催化剂模板棉纤维的盐酸处理对催化性能的影响OA北大核心CSTPCD

The cotton fibers were pretreated with different concentrations of hydrochloric acid and then used as biological templates to prepare fibrous strip biomimetic Ru/Ba-MgO ammonia synthesis catalysts.The effect of cellulose hydrogen bonding in cotton fibers on Ru/Ba-MgO catalysts was investigated by characterization techniques such as XRD,FTIR,FE-SEM,EDS,BET,H2-TPR and TG for cotton fibers,Ba-MgO carriers and Ru/Ba-MgO catalysts.The results showed that H+ in hydrochloric acid solution would break the intra-cellulose molecular hydrogen bonds in cotton fibers,which exposed a large number of highly reactive hydroxyl groups within the cellulose and enhanced the adsorption of Mg2+and Ba2+,and the specific surface area of the Ba-MgO carriers increased significantly and the pore size decreased significantly.Pretreatment of cotton fibers with suitable concentrations of hydrochloric acid can effectively regulate the particle size of the active component Ru in the catalyst and its dispersion,while the incorporation of co-catalyst Ba inhibited the production of RuOx and improved the reduction performance of Ru/Ba-MgO catalyst,which ultimately led to the improvement of ammonia synthesis activity and thermal stability of Ru/Ba-MgO catalyst.When cotton fibers were pretreated with 3mol/L hydrochloric acid solution,the prepared Ru/Ba-MgO-3 catalyst had the best activity at 425℃,10MPa and 10000h-1 reaction conditions with an outlet ammonia volume concentration of 18.37%.