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Five different types of silica catalyst (SBA-15, SBA-15-PO3H2, and three different Si/Al ratio of commercial zeolites (30, 80 and 280) were used to study the transformation of methanol to hydrocarbon (MTH). The aim of this study was to investigate the effect of pore diameter and acidity in the structure of silica catalysts on the process performances in terms of methanol conversion and hydrocarbon selectivity. The mesoporous silica catalysts were prepared by co-condensation method. The catalysts samples were characterized by GC-MS, XRD, BET, and NH3-TPD techniques. The catalytic performance of synthesized and commercial catalysts for MTH process was evaluated using a homemade fixed bed reactor at temperature (300°C). It was found that the liquid hydrocarbon product provided by zeolite catalysts is aromatic hydrocarbons-rich. High Si/Al zeolites with larger pore size lead to higher selectivity and yield to paraffins (C1-C7). In contrast to commercial zeolite catalyst, SBA-15 and its modification with phosphorus species showed no conversion under studied condition. These results indicate that both pore diameter and acidity influence the product distribution in methanol to hydrocarbon process.

Magnesium silicate hydrate was synthesized for using as an adsorbent for different commercial organic dyes. X-ray diffraction (XRD) confirmed the crystalline phase of magnesium silicate hydrate. Some characteristic absorption bands of the magnesium silicate hydrate structure were observed in the Fourier transform infrared spectroscopy (FTIR) spectrum which supported the result identified from XRD data. Analysis of surface area and porosity by surface area analyzer showed that the synthesized magnesium silicate had high surface area of 634.63 m2/g and also showed the average BJH pore size of 3.72 nm. Insight into the sorption isotherm curve, the hysteresis characteristic was clearly observed suggesting a presence of mesopores within the obtained material. Dye adsorption study revealed that the synthesized adsorbent had the strongest affinity to the cationic dye (methylene blue) on account of the negative charge on the surface of the adsorbent. Hence, the adsorption of methylene blue was reached the equilibrium at the fastest time. In all, the results showed a possibility to apply this prepared magnesium silicate materials as a selective adsorbent for cationic dyes.