中文摘要：

采用低过饱和共沉淀法，以Ni（NO3）2·6H2O和Cr（NO3）3·9H2O为原料，NaOH为沉淀剂制备了晶相单一、结晶度高的镍铬类水滑石化合物，并利用XRD，IR及TG-DTA对其结构进行了表征。测定了加入沉淀剂NaOH后，不同n（Ni）：n（Cr）混合盐溶液中混合盐体系pH值的变化情况，探讨了不同因素对镍铬类水滑石制备的影响。将制备的催化剂应用于尿素与丙二醇反应生成碳酸丙烯酯反应中，在反应温度170℃，n（尿素）：n（1，2-丙二醇）=1：1，反应时间180min，催化剂用量0．2g条件下，尿素转化率可达100％，碳酸丙烯酯产率达90％。

英文摘要：

NiCr hydrotalcite-like compounds with different Ni/Cr molar ratios were synthesized by a co-precipitation method. The effects of pH, Ni/Cr molar ratio, temperature and time of hydrothermal treatment on the structffre of the samples were investigated. The synthesized compounds were characterized by XRD, FT-IR and TG-DTG and studied in the catalytic synthesis of propylene carbonate with 1,2-propanediol and urea. The optimal reaction conditions have been determined by using orthogonally arranged experiments, reaction temperature 170℃, 0.2 g, molar ratio of PG to urea 1 ： 1, reaction time 3 h. Under these conditions, urea conversion was nearly 100% and PC yield reached 90%.