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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.