Abstract The influence of pine wood (Pinus Sylvestris) prehydrolysis on the consumption of main reagents (O2 and NaOH) in the subsequent catalyzed oxidation of the obtained lignocelluloses into vanillin and pulp has been studied. Prehydrolysis of the feedstock was performed with HCl in the water and gas phases. Catalytic oxidation was performed in an autoclave in an aqueous–alkaline medium in the presence of CuO as a catalyst. Native lignin was shown to be inhomogeneous in the process of oxidation into vanillin, and in the first approximation lignin consists of two fractions: the first, which is easily and selectively oxidized to vanillin, and the second, which is oxidized slowly and non-selectively. Acid-catalyzed prehydrolysis of wood leads to further differentiation of the lignin into the selectively and non-selectively oxidizing fractions. The developed two-stage process (prehydrolysis of wood and oxidation of the resulting lignocelluloses) decreases the consumption of NaOH in the oxidation process by 2–5 times as compared to the known data down to the values of 3.7–5.2 g per g of vanillin obtained.

中文翻译：

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酸预水解对木材氧化成香兰素和纸浆过程的影响

摘要 研究了松材（Pinus Sylvestris）预水解对随后将获得的木质纤维素催化氧化为香兰素和纸浆中主要试剂（O2 和 NaOH）消耗的影响。原料的预水解是在水相和气相中用 HCl 进行的。催化氧化在高压釜中在碱性水溶液介质中在 CuO 作为催化剂的存在下进行。天然木质素在氧化成香兰素的过程中被证明是不均匀的，在第一个近似值中，木质素由两个部分组成：第一个部分，容易且选择性地氧化成香草醛，第二个部分，缓慢且非选择性地氧化. 木材的酸催化预水解导致木质素进一步分化为选择性和非选择性氧化部分。