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采用微波辐照法对钠基蒙脱土进行了酸化改性,制备出了酸化蒙脱土（H-MMT）固体酸催化剂,并利用X射线衍射、低温物理吸附等技术对催化剂性质进行了表征,结果表明,经微波辐照酸改性的催化剂层状结构没有被破坏,层间距略有下降,结晶度降低;比表面积和孔径都增大,形成了较好的介孔结构;表面酸量增加.这些特性使得催化剂表现出良好的催化活性.而后,以H-MMT为催化剂,系统研究了乳酸正丁酯的微波辅助合成方法,考查了催化剂用量、微波功率以及微波辐照时间对酯化率的影响.结果表明,微波功率200W、辐照15min、催化剂用量6.0%（占乳酸和正丁醇总质量）为最优的酯化条件,在此条件下,酯化率可达72.4%.最后,探讨了微波辅助H-MMT催化合成乳酸正丁酯的机制,发现H-MMT与微波具有协同作用.微波辅助H-MMT催化合成乳酸正丁酯是一种高效、节能、环境友好的方法,具有市场推广前景.

Acidic montmorillonite（H-MMT） was managed to be prepared by treating Na-montmorillonite with H2SO4 under microwave irradiation.The structure and characters of H-MMT were studied by X-ray diffraction（XRD） and nitrogen adsorption/desorption techniques.The results revealed that acid activation did not affect the layer structure,the surface area and pore volume was larger,and the acid amount was increased.Thus,H-MMT exhibits high catalytic activity in the microwave assisted esterification of lactic acid and n-butyl alcohol.After that,the synthesis of n-butyl lactate was performed by the esterification of lactic acid and n-butyl alcohol in the presence of H-MMT as catalyst under microwave irradiation.The synthesis conditions were systematically investigated and the optimum conditions are as follows：the microwave power is 200W,the reaction time is 15min and the catalyst amount is 6.0%.Under the above conditions,the ester yield could reach 72.4%.Compared to conventional heating and sulfuric canalization,microwave and H-MMT have a synergistic effect on the ester yield of n-butyl lactate.Microwave assisted synthesis of n-butyl lactate catalyzed by H-MMT was proved to be high-efficient,economical and eco-friendly.