The invention is a method for improving the hydrothermal stability of silicon based mesoporous materials. Silicon based mesoporous materials and ionic liquids were placed in a closed reactor. The amount of ionic liquids was 5 times of the weight of silicon based mesoporous materials. The reaction kettle was treated at the temperature of 100 and 150 degrees centigrade for 8 times for 12 hours, and then filtered and dried after the end of the reactor. At the end, it was baked for 4 and 6 hours at 500 600. The method is used to treat silicon based mesoporous materials by two times with environmentally friendly ionic liquids, and the dehydration and condensation of silicon hydroxyl on the surface of the porous material on the silicon based mesoporous material under high temperature conditions of ionic liquids, the crosslinking degree of the hole wall is improved and the structural stability of the material is increased, and then the silicon substrate is improved. The purpose of the hydrothermal stability of the porous material. The SBA series silicon based mesoporous materials treated by this method are still able to maintain a good ordered mesoporous structure after 900 C and 100% steam treatment for 17h, and have a larger specific surface and Kong Rong, showing excellent hydrothermal stability. One
【技术实现步骤摘要】
一种改善硅基介孔材料水热稳定性的方法
本专利技术属于介孔材料改性
,具体涉及一种改善硅基介孔材料水热稳定性的后处理方法。
技术介绍
硅基介孔材料,例如MCM-41、MCM-48、SBA-15和SBA-16等,因其具有规则有序的介孔孔道,高比表面和大孔体积等优势,使其在许多领域有着广泛的应用前景,特别是在催化领域,不同类型的硅基介孔材料被人们用作催化剂载体,表现出了良好的载体性能。然而,不同于晶态的沸石材料,硅基介孔材料的孔壁多是由无定型的SiO2构成,骨架硅物种缩合不够完全,孔壁表面存在大量的未交联硅羟基,使得其水热稳定性较差,在高温水热条件(>800℃)下特别容易产生骨架崩塌,从而导致整个材料结构的破坏。正因为当前硅基介孔材料较差的水热稳定性,从而严重限制了其实际应用范围,特别是对一些高温并有水或者水蒸汽存在的诸如催化裂化等催化反应体系。因此,如何改善硅基介孔材料的水热稳定性,已成为目前人们关注的热点之一。目前,提高硅基介孔材料水热稳定性的报道较多,例如在硅基介孔材料的合成体系中引入NaCl、NaF和EDTA等盐类,利用这些盐的“盐效应”,达到增加所合成硅基介孔材料孔壁厚度的目的,从而增加硅基介孔材料的骨架稳定性,提高其水热稳定性;或者对硅基介孔材料表面进行硅烷化处理,提高硅基介孔材料孔壁表面的疏水性,从而减缓水热条件下水分子对硅基介孔材料骨架结构的侵蚀作用,提高硅基介孔材料的水热稳定性。与上述方法相比,增加硅基介孔材料孔壁交联度即增加硅基介孔材料孔壁表面硅羟基的缩合度,是一种更为实际、有效的方法。有文献报道(ChemMater,20 ...
【技术保护点】
1.一种改善硅基介孔材料水热稳定性的方法,其特征在于:采用离子液体对硅基介孔
【技术特征摘要】
1.一种改善硅基介孔材料水热稳定性的方法,其特征在于:采用离子液体对硅基介孔材料进行高温二次处理,利用离子液体对硅基介孔材料表面硅羟基的脱水缩合作用,促进孔壁的交联度,提高硅基介孔材料的结构稳定性,进而改善硅基介孔材料的水热稳定性,具体步骤如下:将硅基介孔材料和离子液体置于密闭反应釜中...
【专利技术属性】
技术研发人员:袁程远,张忠东,潘志爽,谭争国,廖翼涛,曹庚振,孙雪芹,苏怡,孙艳波,张晨曦,张海涛,段宏昌,
申请(专利权)人:中国石油天然气股份有限公司,
类型:发明
国别省市:北京,11
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