Abstract The ultrasound-assisted depolymerization of lignin was successfully conducted over a synthesized PTA/MCM-41 catalyst under different reaction conditions. Firstly, the structure of the prepared PTA/MCM-41 catalyst was characterized by various techniques, and its acidity was determined using Fourier-transform infrared spectroscopy (FT-IR) of pyridine adsorption and temperature-programmed desorption of ammonia (NH3-TPD). Then, the effects of ultrasound frequency, reaction temperature, and reaction time on the distribution and yield of the products of the ultrasound-assisted depolymerization of lignin were studied. The optimum reaction conditions were obtained at an ultrasound frequency of 30%, a reaction temperature of 300 °C, and a reaction time of 6 h. Under the optimum reaction conditions, the conversion of lignin depolymerization was equal to 94.79%, and the yield of phenolic monomers (PM) and lignin bio-oil was 8.37% and 90.58% respectively.

中文翻译：

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超声空化辅助下PTA/MCM-41催化剂催化木质素转化生物油

摘要 在合成的PTA/MCM-41催化剂上，在不同反应条件下成功地进行了木质素的超声辅助解聚。首先，制备的PTA/MCM-41催化剂的结构通过各种技术表征，并使用吡啶吸附和氨程序升温脱附（NH3-TPD）的傅里叶变换红外光谱（FT-IR）测定其酸度. 然后，研究了超声频率、反应温度和反应时间对超声辅助木质素解聚产物分布和产率的影响。最佳反应条件为超声频率30%、反应温度300℃、反应时间6h。在最佳反应条件下，