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Herein, a new template carbonization method is used to prepare calcite‐type nano‐calcium carbonate (CaCO3) with a core–shell structure using calcium hydroxide as a solute and Pluronic F‐127 as a templating and pore‐forming agent. Dopamine hydrochloride is added to control the size of calcium hydroxide particles. The morphology, particle size, and crystal type of CaCO3 are characterized via transmission electron microscopy, X‐ray diffraction, nanoparticle size, and zeta potentiometer. The creation of core–shell calcium carbonate nanoparticles is examined in relation to reaction circumstances (i.e., additive sequence, additive amount, and additive mixing time), carbonization temperature, liquid flow rate, and templates with varying chain lengths. Furthermore, a discussion is held regarding the formation mechanism of spherical core–shell calcium carbonate that is created using the innovative template carbonization method. The results show that the order, amount, liquid flow rate, and template type of additives have a significant effect on the crystal shape of calcium carbonate nanoparticles. The mixing time of additives has a significant effect on the particle size of calcium carbonate nanoparticles. Interestingly, the thickness of the shell depends on the carbonization temperature, and too slow or too fast flow rate will lead to the formation of cyclic calcium carbonate nanoparticles. [ABSTRACT FROM AUTHOR]

MG has a special molecular structure, and MG is an important chemical intermediate with promising applications. Ag−Ce/ZrO2 catalysts with different contents were prepared for hydrogenation of DMO to MG by equal volume impregnation. The content of Ag and the type of additives were screened. According to the effects of different additives on the conversion rate of DMO and the selectivity of MG, Ce was finally selected as the optimal additive metal. These were characterized by XRD, XPS, BET, H2‐TPR. The addition of Ce helps the catalyst to form more oxygen vacancies and Ag2O is more easily reduced to Ag monomers. The performance test results of the catalyst showed that the addition of appropriate amount of Ce has a certain promotion effect on the hydrogenation performance of the catalyst, The yield of MG using the 8Ag−Ce1/ZrO2 catalyst was significantly better than that of the Ag/ZrO2 catalyst. [ABSTRACT FROM AUTHOR]