天然气和二氧化碳转化制合成气的研究──Ⅱ．催化剂失活与再生

Studies of reforming natural gas with carbon dioxide to produce synthesis gas ──Ⅱ. Catalyst deactivation and reactivation

采用ＸＲＤ，ＸＰＳ技术，配合比表面、孔结构测定和催化微反技术，研究了天然气和ＣＯ２转化制合成气催化剂失活机制和再生条件。发现催化剂失活主要是由于活性中心Ｎｉ０聚集并形成晶相，因而降低了催化剂表面活性中心数，其次是由于部分活性中心形成难还原的ＮｉＡ１２Ｏ４物种和催化剂比表面降低。找到了一种催化剂再生的最佳条件，通过使用晶相分散剂Ｂ可以使催化剂恢复到新鲜催化剂的活性。

The deactivated mechanism and the reactivated conditions for the catalysts used in reforming natural gas with carbon dioxide to produce syngas have been studied by using XRD, TPR, XPS techniques, together with determinations of specific Surface area and pore structure, and the micro catalytic reactor. It was found that the main reason of catalytic deactivation is the formation of NiOcrystal thus reducing the number of activity site on the catalyst Surfaces, and the secondary reason is the decrease of surface area and the formation of NiA12O4. on a part of active sites. The optimum conditions for catalyst reactivation were found. The activity can be renewed to the fresh one by the treatment with crystal disperser B.