The Synthesis Of The Layered Double Hydroxides And The Epoxidation For The Unsaturated Esters Under The Hydrotalcites As Catalyst

In this paper, the hydrotalcites was synthesized by using coprecipitation method performed with a solution of NaOH as precipitator. The pillared-hydrotalcites can be obtained through ion exchang method. Hydrotalcites and the intercalated material have been studied by characterization techniques such as XRD, FT-IR, UV–Visa spectroscopy, TG, BET and ICP. The results showed that the anion have intercalated within the LDHs interlayer without modifying its original structure.The catalysts were tested by epoxy reaction of fatty acid ester of this thesis. The results showed that the pillared-hydrotalcites had better selectivity and conversion. The effects of roast conditionswas, different ion in the layer, reaction time, temperature and catalyst reuse ect. performance on the epoxidation of fatty acid methyl ester were discussed in details. The results indicated that the series of catalysts showed certain catalytic activity in epoxidation of fatty acid methyl ester. The highest selectivity and conversion of reaction were 59.36% and 56.14%,respectively. After recycling four times, the activity was also very steadily and the recycle utility rate greater than 90%. The mechanism of the epoxidation for the fatty acid ester under the pillared-hydrotalcites as catalyst was finally investigated.The epoxidation of long carbon chain unsaturated compounds has become one of the hot research topics of the world-class scientists. It showed that the catalysts which were modified by the heteropoly acid anion had better catalytic properties than before modification. Otherwise, the catalyst was easily moved from the reaction system. Hydrotalcite-like compounds, as a new kind of functional material and application in catalysis of epoxidation, have broad prospects.