By employing a sodium silicate + titanium tetrabutoxide + trimethylmyristylammonium bromide system, it has been possible to obtain mesoporous titanosilicateTt-MCM-41-type molecular sieves containing systematically varying titanium contents. The samples obtained possessed a high BET specific surface area and exhibited the perfect hexagonal mesoporous structure characteristic for MCM-41 materialseven when the titanium fraction present was as great as 20 mol%. It has been shown that most of the titanium can be expelled from the structure when the materials are treated with sulphuric acid solution. However. such treatment does not destroy their inherent hexagonal structure, thereby suggesting that the titanium is preferentially localized in the mesopore surface layer.The structure/sorption properties of the materials were investigated by X-ray diffractionmethods and by the adsorptionof n-hexaneand water vapour. A possible mechanism for the formation of such MCM-41-type molecular sieves is proposed which suggests that the use of organometallic ethers M(OR)n' accompanied by ether solubilization with organic micellar templates. leads to the preferential localization of M in the mesopore surface.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.