摘要
以CaSO4为钙源,采用浸渍法对HMCM-22分子筛进行改性,并用XRD、TPD、FT-IR等对催化剂进行了表征,发现HMCM-22分子筛负载CaSO4后仍具有原有的结构和特征,弱酸位的酸强度与酸量变化不明显,但强酸位的酸量略有降低,弱碱与强碱的碱强度略有增加,并且在等摩尔磷酸与月桂醇绿色合成单十二烷基磷酸酯的反应中磷酸转化率得到了显著的提高,表明了CaSO4协同HMCM-22分子筛催化剂酸中心促进了酯化反应。该催化剂具有优良的催化性能。在CaSO4负载量为3.0%,催化剂用量为总反应物质量的2.0%,反应温度为80℃条件下,反应9 h磷酸的转化率达到80.0%,单酯选择性为99.8%。Ca/HMCM-22复合分子筛是一种良好的新催化材料。
The HMCM-22 catalysts were modified by impregnation with CaSO4 which was used as the calcium source of the modification, and then the composite catalysts prepared were characterized by XRD, TPD, FT-IR and so on. The results show that the samples remain the structure and characteristic of the molecular sieve MCM-22. A little variation in the strength and content of the week acid sites, a little decrease on the content of strong acid sites and a little enhancement on the strength of the strong and week basic sites occur after the modification of the HMCM-22 by CaSO4. The Ca/HMCM-22 catalysts exhibit a fine catalytic performance for the synthesis of MPA （monododecylphosphate） by esterification of phosphoric acid with equimolar lauryl alcohol. The conversion of phosphoric acid over the Ca/HMCM-22 catalysts enhances significantly, which indicates that the CaSO4 and the acid site of the HMCM-22 catalyst cooperatively promote the esterification. Under the reaction temperature of 80℃, the catalyst with 3.0% CaSO4 loading and the amount of the used catalyst equals 2.0% of the total mass, the conversion of phosphoric acid and the selectivity of MAP could reach 80.0% and 99.8%, respectively after esterification of 9 hours. It shows that the Ca/HMCM-22 molecular sieve is a kind of good novel catalytic material.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2012年第6期971-976,共6页
Journal of Chemical Engineering of Chinese Universities
基金
材料化学工程重点实验室开放项目
国家重点基础研究规划(973项目
2009CB724701)
