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Potassic rocks are rapidly activated and converted to cancrinite (CAN) zeolites in NaOH solution via microwave-assisted hydrothermal (MH) method. The conditions of zeolization process via MH method are optimized, and the mechanism is illustrated. The phase transition process of potassic rocks is obtained as follows: decomposition of the potassic rocks→zeolite sodalite→zeolite CAN. In this process, the microwave exerts a reinforcement effect by generating the cleavage cracks on the surface of potassic rocks and accelerating the dissolution and crystallization processes. The synthesized zeolite CAN exhibits the maximum adsorption capacity of 6.5 mg g−1 for methylene blue. In addition, the filtrate is further used to prepare linda type A (LTA) zeolites by conventional hydrothermal synthesis method. The synthesized zeolite LTA presents the cubic morphology with rounded corners, and its Ca2+ ion exchange capacity could reach 335.6 mg CaCO3 g−1.

A series of Zr-containing Mg-Al hydrotalcite-like (HTl) precursors were prepared using co-precipitation method with Zr4+: (Al3+ + Zr4+) from 0 to 0.7. It was demonstrated by X-ray diffraction that the yield of the HTl phase declined on increasing of Zr content. Then, Mg-Al-Zr mixed oxide (CHT-Zr) catalysts were obtained by calcining of the corresponding HTl precursors and they all exhibited mesoporous structure after heat treatment. Based on systemic characterization, it was observed that the amount of Zr additive showed a great effect on the structure and acidic-basic property of CHT-Zr samples. Meanwhile, such CHT-Zr catalysts were effective catalysts for the glycerol carbonate (GLC) synthesis from glycerol and urea. Afterwards, the function of acidic and basic sites in each reaction path identified in this research was elucidated based on the reactant conversion and product selectivity. It proved that the acidic sites were inclined to promote the reaction towards GLC synthesis, while all the paths towards the by-products were significantly catalyzed by the basic sites. However, the catalysts with extra strong acidity did not facilitate the GLC production due to poisoning of surface active sites by urea adsorption. So, a well-balanced acidic-basic property was important to obtain high GLC yield with good selectivity. Among all the catalytic samples, the catalysts with Zr4+: (Al3+ + Zr4+) = 0.3 showed the best catalytic performance with 87.8% yield of GLC. Moreover, different reaction parameters such as reaction temperature, reaction time, catalyst amount and vacuum degree were investigated and optimum conditions were established. Additionally, this catalyst could be readily recycled and reused for at least four times without any activation treatment, while still possessing high activity.

A series of mesoporous nano-MgO-ZrO2 with various Mg:Zr atomic ratios were prepared via simple co-precipitation process without addition of a template. It was demonstrated by XRD, N2 adsorption-desorption and TEM that these samples still kept well mesoporous structure even after calcination at 600 °C. During the preparation process, divalent Mg2+ ions could be incorporated into tetragonal ZrO2 lattice to form a solid solution. More important, the surface basic density of these catalysts closely depended on their Mg content. Then, the resulting MgO-ZrO2 catalysts were used as basic catalysts for the dipropyl carbonate (DPC) synthesis via transesterification of n-propanol and dimethyl carbonate. The relationship between the basic property of solid base and their catalytic performance was clarified in detail. Among all the materials, the catalyst with Mg:Zr atomic ratio = 0.5 showed the best catalytic performance. Under the suitable reaction conditions, the yield of DPC could reach 98.5% with 100% selectivity. In addition, based on the reusability test and catalyst characterization, this catalyst exhibited extraordinary structure stability and it could be reused at least four times without obvious loss of reactivity.

A series of Mg-Al-Y mixed oxides (CHT-Y) with different Y 3 + :(Al 3 + + Y 3 + ) atomic ratios were obtained by thermal decomposition of Y-containing hydrotalcite-like compounds. Then, they were characterized using XRD, TGA, XPS, SEM, ICP, CO 2 -TPD and N 2 adsorption-desorption measurement. Meanwhile, all the mixed oxide catalysts were evaluated for the synthesis of diethyl carbonate (DEC) from ethyl carbamate (EC) and ethanol. The results showed that the texture, structure, basic property as well as catalytic activity of CHT-Y were closely associated with the content of Y in the catalyst. Importantly, the role of basic sites was studied in overall reaction and in every comprising reaction path identified in this research. It was found that the reaction of EC and ethanol could be improved by the moderate and strong basic sites of catalyst, while the side-reactions towards undesired products were strongly catalyzed over the catalyst with high basic strength. As a result, the best result was achieved over the catalyst with Y 3 + :(Al 3 + + Y 3 + ) = 0.3. Under the optimal reaction conditions, the yield of EC reached 63.8% with a high DEC selectivity of 81.6%. Furthermore, the reusability test and catalyst characterization indicated that CHT-Y catalyst was heterogeneous and could be reused at least fourth time without obvious loss of reactivity.