木塑复合材料废弃物热解转化及其产物构成的烷基化调控机理

As an efficient way of using all-components of biomass, wood plastic composite (WPC) with interesting mechanical and physical properties together with their sustainable character has triggered various activities in building & construction products, automotive components, industrial & consumer goods, and others in recent years. Its market is expected to grow rapidly in the next five years due to the increasing demand for decking across the globe, especially in China. After times of recycling and reuse, serious deterioration resulting from its macromolecular degradation made WPC unsuitable to use as a material and became a new solid waste need to be disposed harmlessly. However, its elemental composition has not changed much and thus can be used as raw material for bio-energy production. In this project, polyolefin-based WPC will be fast pyrolyzed, and then the produced liquid products will be regulated under solid acid catalysis through self-alkylation reactions occurred between the alkenes and bio-oils, generating from the pyrolysis of polyolefin and biomass components in WPC, separately. In this process, hydroxyl group-containing compounds in crude bio-oil such as alcohols, phenols and acids are hoped to be transformed into hydrophobic ethers, substituted phenols and ester, respectively. Thus, the upgraded crude bio-oil will be endowed with high heating value, good storage stability, low corrosivity and miscibility with oil fuel. Influence factors such as raw material contents and operating conditions on selectivity, product structure and compositions of both WPC pyrolytic liquefaction process and catalytic alkylation reactions will be focused on to figure out the regulatory mechanisms and structure-activity relationship of WPC pyrolysis products, to reveal multi-coupling mechanisms of WPC’s chemistry components during fast pyrolysis process, and finally, to achieve more effective alkylation upgrading results. The basic theory and technical principles will be set up for converting WPC effectively into organic compounds of high quality and high additional value by combinatorial regulation of the product structure & compositions in both WPC pyrolysis and pyrolyzate alkylation processes.

近年来，作为生物质全组分利用的高效途径，木塑复合材料以其优异的物理、力学和环境友好性在建筑产品、汽车零部件、工业和消费品等领域得到广泛应用。随着全球，尤其是我国对装饰需求的增加, 未来五年其市场增速将更为迅猛。WPC经多次循环利用后，大分子降解使其力学性能降低不适于继续服役，作为一种新型固体废弃物必须进行处理，由于其元素组成未发生明显变化，可用作制备生物质能源的原料。本项目将聚烯烃WPC进行快速热解，并在固体酸催化剂下，对其热解产物构成进行烷基化调变，以期获得热值高、储存稳定性好、腐蚀性低的高品质液态产物。通过研究WPC快速热解条件及产物构成规律，热解产物烷基化调变过程的催化剂体系、反应条件和选择性，明确WPC复杂体系中全组分耦合热分解规律、热解产物构成的烷基化调变规律以及烷基化效率的控制方法。形成以产物增值利用为导向、废旧WPC热解液化/烷基化高效转化过程的科学理论，建立基本技术方法。

近年来，作为生物质全组分利用的高效途径，木塑复合材料以其优异的物理、力学和环境友好性在建筑产品、汽车零部件、工业和消费品等领域得到广泛应用。随着全球，尤其是我国对装饰需求的增加, 未来五年其市场增速将更为迅猛。WPC经多次循环利用后，大分子降解使其力学性能降低不适于继续服役，作为一种新型固体废弃物必须进行处理。WPC主要由生物质和塑料组成，具有较高的能源价值，因而可通过快速裂解技术将其废弃物转化为高品位的生物燃油。. 本项目以聚丙烯木塑为聚烯烃WPC代表性实验材料，分别从WPC原料组成与特性的调控、热化学条件的控制、以及产物构成调变等方面入手，将聚丙烯WPC材料进行快速裂解液化，并以WPC中聚丙烯组分裂解产物中的烯烃单体作为全部或部分烯烃供体，与WPC中木质组分热解产物在固体酸催化的条件下进行O-烷基化构成调变，成功制得了具有热值高、腐蚀性低、储存稳定性好的高品质改性液态产物。通过系统研究WPC快速热解条件及产物构成规律，热解产物烷基化调变过程的催化剂体系、反应条件和选择性，明确WPC复杂体系中全组分耦合热分解规律、热解产物构成的烷基化调变规律以及烷基化效率的控制方法。形成以产物增值利用为导向、废旧WPC热解液化/烷基化高效转化过程的科学理论，建立基本技术方法。此外，为了降低木塑热解产物构成复杂性对后期改性带来的不利影响，从简化木塑热解产物构成出发，通过研究分子筛，金属氧化物作用下木塑催化裂解产物组成及分布规律，探究了催化剂作用下木塑可控裂解机制。. 本项目以废弃木塑复合材料为研究对象，通过快速热解技术，将其高效转化为生物质能源/化学品而加以回收再利用，有效地延长了木材生物质资源的使用周期，实现了资源的梯级利用，大幅度提高了资源利用效益，是一种原子经济的途径。. 本项目发表论文8篇，其中SCI收录论文6篇，国内核心期刊论文2篇，申请中国专利3项，其中1项已获授权并成功转让。.