Co-pyrolysis of biomass and waste plastics is a long-term strategy to achieve efficient waste management and generate valuable fuels. The cellulose and polyethylene were chosen as typical representatives for biomass and plastics in this work. Reactive force field molecular dynamic and density functional theory were employed to investigate the co-pyrolysis mechanism of cellulose and polyethylene which were not readily achieved only by experiments. The hydrocarbon and H radicals from polyethylene respectively interact with the alcoholic groups and furans which contributes to producing alcohols and suppresses the generation of aldehydes and ketones. The energy barriers of rate controlling steps for producing long-chain alcohols (about 669.40 kJ/mol) in co-pyrolysis of cellulose and polyethylene are obviously smaller than those for producing oxy-compounds in cellulose pyrolysis alone. The formations of furan alcohols are easy with low energy barriers (22.19, 16.40 and 22.66 kJ/mol, respectively) in the presence of polyethylene. The co-pyrolysis of cellulose and polyethylene also promotes the formation of CH. The polyethylene has a positive effect on the improvement of major co-pyrolysis products. The reactive force field molecular dynamic simulation and density functional theory seems promising to determine the co-pyrolysis mechanisms of biomass and waste plastics at microcosmic level and help to produce high-quality fuels.

生物质和废塑料的共热解是实现有效废物管理并产生有价值的燃料的长期战略。纤维素和聚乙烯被选为这项工作中生物质和塑料的典型代表。利用反应力场分子动力学和密度泛函理论研究了纤维素和聚乙烯的共热解机理，而仅通过实验是不容易实现的。碳氢化合物和来自聚乙烯的H自由基分别与醇基和呋喃相互作用，这有助于产生醇并抑制醛和酮的产生。在纤维素和聚乙烯的共热解中生产长链醇（约669.40 kJ / mol）的速率控制步骤的能垒明显小于仅在纤维素热解中生产含氧化合物的那些。在聚乙烯存在下，呋喃醇的形成容易且具有低能垒（分别为22.19、16.40和22.66 kJ / mol）。纤维素和聚乙烯的共热解也促进CH的形成。聚乙烯对主要共热解产物的改进具有积极作用。