Two ways of catalytic depolymerization of native and isolated wood lignins are described: the peroxide delignification of hardwood (aspen, birch) and softwood (abies) in the medium of acetic acid – water over TiO₂ catalyst and the thermal dissolution of organosolv lignins (ethanol-lignin and acetone-lignin) in supercritical alcohols (ethanol and butanol) over solid Ni-containing catalysts.

The catalyst TiO₂ in rutile modification has the higher activity in wood peroxide delignification at 100 °C as compared to TiO₂ in anatase modification. The results of kinetic studies and optimization of the processes of peroxide depolymerization of hardwood (aspen, birch) and softwood (abies) lignins in the medium of acetic acid – water over catalyst TiO₂ (rutile) at mild conditions (≤100 °C, atmospheric pressure) are compared. The catalyst TiO₂ initiates the formation of OH and OOH radicals from H₂O₂ which promote the oxidative fragmentation of wood lignin. In this case, the peroxide depolymerization of softwood lignin, constructed from phenylpropane units of guaiacyl-type proceeds more difficult than the hardwood lignins, mainly containing syringyl-type units.

The solid and soluble products of peroxide catalytic delignification of wood under the optimized conditions were studied by FTIR, XRD, GC–MS and chemical methods. Regardless of the nature of wood the cellulosic products have a structure similar to microcrystalline cellulose. The soluble products mainly consist of monosaccharides and organic acids. Aromatic compounds are present only in a low amount which indicates the oxidative degradation of aromatic rings of lignin phenylpropane units under the used conditions of wood catalytic delignification.

The processes of thermal dissolution of acetone-lignin and ethanol-lignin from aspen-wood in supercritical ethanol and butanol over Ni-containing catalyst (NiCu/SiO₂, NiCuMo/SiO₂) are compared. The composition, structure and thermal properties of organosolv lignins were studied with the use of FTIR, GPC, ¹H – ¹³C HSQC NMR, DTA and elemental analysis.

The influence of a composition of Ni-containing catalyst on the thermal conversion in supercritical butanol and ethanol of ethanol-lignin and acetone-lignin was established. The highest conversion of lignins (to 93% wt.) in supercritical alcohols and the highest yield of liquid products (to 90% wt.) were achieved at 300 °C in the presence of catalyst NiCuMo/SiO₂.

Scheme of green biorefinery of wood based on the use of non-toxic and low-toxic reagents (H₂O₂, H₂O, acetic acid, ethanol, butanol) and solid catalysts (TiO₂, NiCuMo/SiO₂) is suggested.

描述了天然和分离的木质木质素的两种催化解聚方法：在乙酸介质中的硬木（白杨木，桦木）和软木（冷杉木）的过氧化物脱木素作用；水在TiO ₂催化剂上的溶解；有机溶剂木质素（乙醇）的热溶解固态含镍催化剂上的超临界醇（乙醇和丁醇）中的β-木质素和丙酮-木质素）。

与锐钛矿型改性的TiO ₂相比，金红石型改性的TiO ₂在100°C的木质过氧化物脱木质素中具有更高的活性。在乙酸-水介质中，在温和条件下（≤100°C，在催化剂TiO ₂（金红石）上，水-乙酸中的硬木（树皮，桦木）和软木（冷杉）木质素的过氧化物解聚的动力学研究和优化过程的结果），比较大气压）。催化剂TiO ₂引发由H ₂ O ₂形成OH和OOH自由基促进木质素的氧化破碎。在这种情况下，由愈创木脂型的苯基丙烷单元构成的软木木质素的过氧化物解聚比主要包含丁香基型单元的硬木木质素更加困难。

通过FTIR，XRD，GC-MS和化学方法研究了在最佳条件下木材过氧化物催化脱木素的固体和可溶性产物。不管木材的性质如何，纤维素产品的结构都类似于微晶纤维素。可溶性产物主要由单糖和有机酸组成。芳族化合物仅以少量存在，这表明在所用的木质催化脱木素条件下，木质素苯基丙烷单元的芳环被氧化降解。

比较了含镍催化剂（NiCu / SiO ₂，NiCuMo / SiO ₂）上超临界乙醇和丁醇中丙酮-木质素和乙醇-木质素在白杨木中的热溶解过程。使用FTIR，GPC，¹ H – ¹³ C HSQC NMR，DTA和元素分析研究了有机溶剂木质素的组成，结构和热性能。

建立了含镍催化剂的组成对乙醇-木质素和丙酮-木质素在超临界丁醇和乙醇中热转化的影响。在催化剂NiCuMo / SiO ₂的存在下，在300°C下，木质素在超临界醇中的转化率最高（至93％wt。）和液体产品的最高产率（至90％wt。）。

提出了基于无毒和低毒试剂（H ₂ O ₂，H ₂ O，乙酸，乙醇，丁醇）和固体催化剂（TiO ₂，NiCuMo / SiO ₂）的木材绿色生物精炼方案。。