Designing catalytic pyrolysis of biomass for green hydrogen production.

该项目旨在解决设计和优化替代能源生产技术的需求，以实现到2050年的碳中和目标。本项目研究的技术主要基于生物质主要通过热解过程生产氢气，即在没有氧气的情况下，通过高温下有机物的热化学分解过程。一般来说，生物质的热解产生三种物质：生物油、生物炭和热解气体。生物油是一种深褐色液体，含有较小的羰基化合物、糖基化合物和木质素基化合物，经过提升(降低其水分和氧气含量)后，有可能取代传统的石油燃料。生物炭是一种多孔性(表面积约1400平方米/克)、高碳质(碳含量：65-90%)的材料，由于其吸附性能，可用于过滤和捕获有毒污染物。热解气体是氢、碳氢化合物气体(C1-C4)、二氧化碳、一氧化碳和硫化氢的混合物。通过改变热解工艺条件(包括反应气氛、温度、升温速率和蒸汽停留时间)，可以获得不同的生物油、生物炭和气体产品的产率和组成。这个项目的目标是最大限度地提高气体产品流的氢气浓度，这可以通过选择合适的催化剂来实现，包括基于沸石的裂化催化剂。一种在干旱和半干旱环境中自然生长的植物(40%纤维素，28%半纤维素，20%木质素)和纤维素已被选为该植物的替代品，以建立对热解过程、其机理和动力学的基本了解。该项目的目标是：(I)通过反应工程(优化反应条件，对产品进行表征，将底物从纤维素改变为其建筑碎片，即葡萄糖，纤维二糖)，建立对纤维素热解的深入了解；(Ii)选择催化剂并进行纤维素的催化热解，包括。(I)研究传统使用的Ni/Al_2O_3催化剂上甲烷水蒸气重整裂解气体的后处理，并确定热解气体混合物中的杂质对过程的影响；(Iv)对实际生物质样品进行热解和催化热解，并比较(I)和(Ii)中的结果。

The project aims to address the need for designing and optimizing alternative energy production technologies to meet the carbon-neutrality aims by 2050.The technology studied herein is based on production of hydrogen from biomass primarily through a pyrolysis process, i.e. through the process of thermochemical decomposition of organic matter at the elevated temperatures, in the absence of oxygen. In general, pyrolysis of biomass results in three phases of matter: bio-oil, biochar and pyrolytic gas. Bio-oil is a dark brown liquid that contains small carbonyl compounds, sugar-based compounds and lignin-based compounds, and after uplifting (to reduce its moisture and oxygen content) has a potential to replace conventional petroleum fuel. Biochar is a porous (surface area ~1400 m2/g) highly carbonaceous (C content: 65-90%) material that thanks to its adsorptive properties is used for filtration and toxic pollutant capture. Pyrolytic gases are a blend of H2, hydrocarbon gases (C1-C4), CO2, CO and H2S. By varying the pyrolysis process conditions (incl. reaction atmosphere, temperature, heating rate and vapour residence time), different yields and compositions of bio-oils, bio-chars and gaseous products can be achieved. This project targets maximisation of gaseous product stream with maximal concertation of hydrogen, and this can be potentially achieved by selecting appropriate catalysts, including zeolite based cracking catalysts.The chosen biomass feedstock is alfa plant (approx. 40% cellulose, 28% hemicellulose, 20% lignin), a spontaneously growing plant in arid and semi-arid environments, and cellulose has been selected as a proxy of this plant to build a fundamental understanding of the pyrolysis process, its mechanisms and kinetics.The project objectives are: (i) to build a robust understanding of cellulose pyrolysis through reaction engineering (optimization of reaction conditions, characterising the products, changing the substrate from cellulose to its building fragments, i.e. glucose, cellobiose); (ii) to select catalysts and perform catalytic pyrolysis of cellulose, incl. conditions optimisation to build understanding of the catalytic process; (iii) studying post processing of the pyrolytic gas via steam methane reforming on traditionally used Ni/Al2O3 catalysts and determining the effect of impurities present in the post-pyrolysis gas mixture on the process; (iv) to perform pyrolysis and catalytic pyrolysis on real biomass sample and compare the results obtained in (i) and (ii).