Pretreatment is one of the key steps in lignocellulosic biorefinery. Single stage acid pretreatment is often insufficiently satisfactory to overcome biomass recalcitrance, as the presence of insoluble lignin with repolymerized structure always hinders biomass fractionation and saccharification. In this work, a sequential acid-alkali pretreatment was developed to promote biomass fractionation, saccharification and holistic utilization. Results indicated that the addition of 2-naphthol in acid pretreatment enhanced lignin reactivity towards alkali post-treatment. A synergistic effect was observed between 2-naphthol additive and alkali post-treatment in improving biomass saccharification. As a result, up to 90 % of carbohydrates in raw biomass was released and recovered as fermentable sugars after pretreatment and enzymatic hydrolysis. Besides, enzymatic hydrolysis at cellulose loading of 8 % led to a high glucose concentration of 75.51 g/L in enzymatic hydrolysate. Moreover, lignin recovered after alkaline hydrogen peroxide (AHP) treatment and enzymatic hydrolysis both showed great adsorption performance for lead ions, presenting value-added lignin materials. Finally, the mass balance and energy analysis revealed an optimal fractionation of poplar biomass that could achieve an energy recovery of 86 %.

预处理是木质纤维素生物精炼的关键步骤之一。单级酸预处理通常不足以克服生物质的顽固性，因为具有再聚合结构的不溶性木质素的存在总是阻碍生物质的分馏和糖化。在这项工作中，开发了一种顺序酸碱预处理，以促进生物质的分馏、糖化和整体利用。结果表明，在酸预处理中加入2-萘酚增强了木质素对碱后处理的反应性。观察到2-萘酚添加剂和碱后处理在改善生物质糖化方面的协同作用。结果，在预处理和酶促水解后，原料生物质中高达 90% 的碳水化合物被释放和回收为可发酵糖。除了，在 8% 纤维素负载下的酶促水解导致酶促水解产物中的高葡萄糖浓度为 75.51 g/L。此外，碱性过氧化氢（AHP）处理和酶解后回收的木质素均对铅离子表现出很好的吸附性能，是具有附加值的木质素材料。最后，质量平衡和能量分析揭示了杨树生物质的最佳分馏，可以实现 86% 的能量回收。