✍ Scribed by Yang Jian-Ming; Lü Jian
No coin nor oath required. For personal study only.
Phenylsulfonic acid functionalized mesoporous silica was synthesized by condensation of tetraethylorthosilicate with phenyltrimethoxysilane, and then sulfonation using 30% fuming sulfuric acid. The material was characterized using FT-IR, DSC, XPS, TEM and N 2 adsorption/desorption measurements. DSC revealed that sulfonic acid group of the catalyst was decomposed at 354.8 ℃, indicating that the catalyst exhibited high thermal stability. XPS showed that there existed three kinds of different silicon species on surface of the catalyst. The catalytic performance of the catalyst was evaluated using transetherification of alcohols with dimethoxymethane. It was found that among primary alcohols, the selectivities of the two long-chain alcohols for n-dedocanol and n-tetradecyl alcohol were higher than 97.0% at the conversions of 43.6% and 65.3%, respectively, while the selectivities of the short-chain alcohols except for n-hexanol were less than 90.0% at the conversions of over 80.0%. Due to steric barrier, the secondary alcohols such as iso-butanol and cyclohexanol afforded conversions of 79.4% and 60.5%, and the selectivities of the two alcohols were more than 90.0%. The sequence in conversion of the substituted phenols is as follows: p-nitrophenol＞p-fluorophenol≥p-bromophenol＞p-cresol＞m-cresol.
📜 SIMILAR VOLUMES
## Abstract Heteropoly acids (HPA), such as tungstophosphoric acid (H~3~PW~12~O~40~ · __x__H~2~O) (HPW), molybdophosphoric acid (H~3~PMo~12~O~40~ · __x__H~2~O) (HPMo) and tungstosilicic acid (H~4~SiW~12~O~40~ · __x__H~2~O) (HSiW) were supported on mesoporous silica such as MCM‐41, FSM‐16 and SBA‐15