An aqueous phase Pd nanoparticles (NPs) system reduced and stabilized only by sodium lignosulfonate (SLS) was found to exhibit a favorable catalytic performance in hydrodeoxygenation of vanillin to produce 2-methoxy-4-methylphenol (MMP). Ultraviolet-visible spectroscopy (UV-Vis), transmission electron microscope (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) characterization were carried out to confirm the formation of NPs, and the influence of various metal salt precursors, temperatures, stirring rates and SLS concentrations on catalyst preparation. It was revealed that the optimized Pd NPs with an average diameter of 14.63 nm had achieved a 99.8 % vanillin conversion and a 98.6 % MMP selectivity under the conditions of 1 mmol vanillin, n_(Vanillin)/n_(Pd) = 300, 1 MPa H₂, 70 °C and 2 h. Besides, MMP, the target product, was found an auto-separation property from the aqueous catalyst system due to its less solubility in water. Furthermore, this aqueous Pd NPs catalyst was demonstrated to have stable catalytic activity in the hydrodeoxygenation of vanillin by ten-run tests with favorable conversions of vanillin above 98 %. The selectivity of MMP stayed above 92 % within five runs and still maintained 85.4 % after ten runs. Thus, an environmentally friendly and mild-conditioned hydrodeoxygenation method of vanillin into MMP was developed by using SLS, one of the by-products of the pulp and paper industry.

发现仅通过木质素磺酸钠 (SLS) 还原和稳定的水相 Pd 纳米粒子 (NPs) 系统在香兰素加氢脱氧生产 2-甲氧基-4-甲基苯酚 (MMP) 中表现出良好的催化性能。进行了紫外-可见光谱 (UV-Vis)、透射电子显微镜 (TEM)、X 射线衍射 (XRD)、X 射线光电子能谱 (XPS) 和傅里叶变换红外 (FT-IR) 表征以确认形成NPs 的影响，以及各种金属盐前体、温度、搅拌速率和 SLS 浓度对催化剂制备的影响。据透露，平均直径为 14.63 nm 的优化 Pd NPs 在 1 mmol 香草醛、n_(香草醛) / n _(Pd) = 300, 1 MPa H ₂ , 70 °C 和 2 h。此外，由于目标产物 MMP 在水中的溶解度较低，因此发现其与水性催化剂体系具有自动分离特性。此外，该水性 Pd NPs 催化剂通过十轮试验证明在香兰素加氢脱氧中具有稳定的催化活性，香兰素的转化率超过 98%。MMP 的选择性在 5 次运行内保持在 92% 以上，10 次运行后仍保持 85.4%。因此，利用纸浆和造纸工业的副产品之一 SLS，开发了一种环境友好、条件温和的香草醛加氢脱氧法制备 MMP。