The liquefaction of biomass in ethanol, at the critical point, has high potential due to low temperature and pressure (243 °C, 63 bar) when compared with water (374 °C, 220 bar). The current study deals with the fractionation of birch wood powder which was liquefied under supercritical ethanol over acidic or non-acidic catalysts, 5 wt % Fe-Beta-H-150 and 5 wt % Fe–SiO₂, respectively. Based on the results, the reaction mechanism for the formation of lignin degradation products was proposed. The main phenolic product was isoeugenol over 5 wt % Fe-Beta-H-150 while intermediate products, i.e. such as coniferyl, and sinapyl alcohol, 4-propenyl syringol, syringaresinol, as well as syringyldehyde reacted rapidly further. The thermodynamic analysis was performed by Joback approach and using Gibbs-Helmholtz equation supporting the obtained results.

与水（374°C，220 bar）相比，由于低温和低压（243°C，63 bar），生物质在临界点的液化具有很高的潜力。当前的研究涉及桦木粉末的分馏，该桦木粉末在超临界乙醇中分别在酸性或非酸性催化剂（分别为5 wt％的Fe-Beta-H-150和5 wt％的Fe-SiO _2）下液化。根据结果​​，提出了木质素降解产物形成的反应机理。主要的酚类产品是超过5 wt％Fe-Beta-H-150的异丁香酚，而中间产品即例如松柏油和芥子醇，4-丙烯基丁香酚，丁香树脂醇以及丁香基醛进一步迅速反应。热力学分析是通过Joback方法进行的，并使用Gi​​bbs-Helmholtz方程式来支持所获得的结果。