Functionalisation of porous silica powders in a fluidised-bed reactor with glycidoxypropyltrimethoxysilane (GPTMS) and aminopropyltriethoxysilane (APTES)

This work deals with the use of a new solventless process for chemical grafting of solid particles. The process was previously used (Lazghab et al., 2008) to hydrophobise silica supports with conventional silanisation reagents such as octadecyltrichlorosilane (OCDTS) and trimethylchlorosilane (TMCS). The aim of the present work was to extend the applicability of this process to other types of surface functionalisation treatments in addition to hydrophobisation.Porous silica powder was treated using two commonly used coupling reagents: glycidoxypropyltrimethoxysilane (GPTMS) and aminopropyltriethoxysilane (APTES). The results showed that the chemical grafting can be performed successfully by the new process in the complete absence of any organic solvent. The two reagents were successfully anchored on a silica surface and achieved high surface coverage in only a few minutes. The hydrophobic effect provided by the treatment was also analysed and discussed.