分子筛催化剂催化合成聚甲氧基二甲醚  

Synthesis of polyoxymethylene dimethyl ethers over zeolite catalysts

作　　者：曹健[1,2] 朱华青[1] 王辉[1] 黄立志[1,2] 秦张峰[1] 樊卫斌[1] 王建国[1] 

机构地区：[1]中国科学院山西煤炭化学研究所 煤转化国家重点实验室,山西太原030001 [2]2中国科学院大学,北京100049

出　　处：《燃料化学学报》2014年第8期979-986,共8页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金(21273264);国家重点基础研究发展规划(973计划,2011CB201403,2011CB201406)

摘　　要：以甲醇、甲缩醛和三聚甲醛为原料,考察了分子筛孔道结构、晶粒粒径、酸性及反应体系对合成聚甲氧基二甲醚反应性能的影响,并筛选出最佳反应条件.结果表明,HMCM鄄22分子筛具有良好的催化性能.在最佳反应条件下,以甲醇与三聚甲醛为原料,DMM2～8的选择性为65.1%;而以甲缩醛和三聚甲醛为原料,DMM2～8的选择性则达到90.6%.NH3鄄TPD结果表明,弱酸位有利于三聚甲醛解聚为甲醛,中强酸位促进长链分子生成,而强酸位导致DMM为主要产物.Synthesis of polyoxymethylene dimethyl ethers was carried out on HMCM-22, A1-YNU-1 and MOR zeolites by the condensation of trioxane and methanol or methylal. The crystal structures and surface acidity of the catalysts were characterized by XRD, SEM and NH3-TPD. It was found that DMM2～8 selectivity was influenced by the acid strength and density of zeolites and reaction conditions. HMCM-22 showed much higher selectivity to DMM2_8 than A1-YNU-1 and MOR. Under the optimal conditions, the DMM2_8 selectivity reached 65.1% and 90.6% in ME/TRIox and DMM/TRlox systems respectively. It was shown that the moderately strong acid sites were probably responsible for the werefor DMM. formation of long chain DMMn, while the strong acid sites

关 键 词：HMCM鄄22 聚甲氧基二甲醚 甲缩醛 甲醇 三聚甲醛 

分 类 号：O634[理学—高分子化学]