Manipulating the H2:CO ratio in syngas using staged catalysis and process conditions for targeted end-use applications.

城市固体废物目前未得到充分利用，大多数最终被填埋或焚烧。城市固体废物(MSW)的热处理具有巨大的潜力，可以生产可持续的合成气，可以直接用于发动机、涡轮机和锅炉，或被加工成生产一系列高价值燃料和化学品。已经有几个报告强调了H2：CO比对于产品合成气的最终用途应用的重要性。例如，Song和Guo描述了利用合成气生产潜在的最终用途合成气体的范围，例如通过Fischer Tropsch合成的液体燃料，通过氢甲酰化反应的高价值化学品(如醛和醇)，通过与合成气催化反应生产甲醇等。合成气的性质，特别是H2：CO的比率影响合成气的潜在最终用途合成，例如，Fischer Tropsch的理想H2：CO比率约为2.0，但对于氢甲酰化反应，最佳的H2：CO比率约为1.0[3]。Majewski和Wood[4]报告说，根据所使用的催化剂类型和工艺条件，H2/CO比在1.7、2.15之间可用于生产液态碳氢燃料的费托加工。H2/CO比在1.5-2之间也可用于生产甲醇或合成二甲醚。将使用一系列催化剂(例如单层/多层)和优化的反应器(S)设计来探索MSW原料的分级催化，以生产特定最终用途的高质量合成气，并具有目标H2：CO比，例如费托原料气。催化剂在反应中起着重要的作用，但它们存在一系列问题，如失活、温度稳定性和选择性，因此将探索新的催化剂合成方法以解决当前的问题/局限性。此外，越来越多的注意力集中在二氧化碳捕获上，因此将探索就地捕获二氧化碳以改善产品组成和排放。扫描电子显微镜、透射电子显微镜、X射线衍射仪、X射线光电子能谱、GS-MC、高效液相、TPO等分析技术将用于研究催化剂、气体和任何液体成分。该项目的总体目标是开发一种利用城市固体废物(MSW)生产高质量合成气的热工艺，并了解工艺参数和催化剂对该工艺的影响。这项研究的目标如下：1.确定目标最终用途的最佳H2：CO比率。考察了水蒸气和二氧化碳反应气氛对垃圾及其组分热解-催化重整制氢比的影响。考察催化剂类型对城市生活垃圾及其组分水蒸气/二氧化碳重整反应的影响，目的是制备具有较高催化活性和稳定性的催化剂，以提高合成气产量和减少碳生成，最大限度地提高氢和一氧化碳产量。研究了垃圾热解气体水蒸气/二氧化碳重整制取合成气的最佳工艺参数，如催化剂温度、催化剂配比和水蒸气/二氧化碳流量。研究合成气生产中最大限度地利用H2和CO的过程中的附加阶段(S)，例如通过二氧化碳捕获或添加蒸汽/二氧化碳。

Municipal solid waste is currently underutilised with most ending up in landfill or being incinerated. The thermal processing of municipal solid waste (MSW) has great potential to produce sustainable syngas that can used directly in engines, turbines and boilers or be processed to produce a range of high value fuels and chemicals. There have been several reports which highlight the importance of the H2:CO ratio in relation to the end use application of the product syngas. For example, Song and Guo describe the range of syntheses possible using syngas to produce, for example liquid fuels through Fischer Tropsch synthesis, high value chemicals (e.g. aldehydes and alcohols) through the hydroformylation reaction, production of methanol through catalytic reaction with syngas etc. The properties of the syngas, in particular the H2:CO ratio, influence the potential end-use synthesis of the syngas, for example an ideal H2:CO ratio for Fischer Tropsch is around 2.0, but for the hydroformylation reaction the optimum H2:CO ratio is around 1.0 [3]. Majewski and Wood [4] have reported that a H2/CO ratio between 1.7, 2.15 can be used for Fischer Tropsch processing for the production of liquid hydrocarbon fuels, depending on the type of catalyst used and the process conditions. A H2/CO ratio between 1.5-2 can also be used for production of methanol or for dimethyl-ether synthesis. Staged catalysis of MSW feedstock will be explored using a range of catalysts (e.g. single/multi-layered) and optimised reactor(s) design to produce high quality syngas with targeted H2:CO ratio for a particular end-use application e.g. Fischer-Tropsch feedstock gas. Catalysts play an important part in reactions however they suffer from a range of issues from deactivation, temperature stability, and selectivity thus new novel catalysts synthesis will be explored to address current issues/limitations. Additionally, increased attention is focusing on carbon dioxide capture therefore in-situ CO2 capture to improve product composition and emissions will be explored. Analytical techniques such as SEM, TEM, XRD, XPS, GS-MC, HPLC, TPO, will be used to investigate catalysts, gases and any liquid compositions. The over aim of the project is to develop a thermal process for municipal solid waste (MSW) to produce high quality syngas with a defied H2:CO ratio adaptable for particular end-use applications, together with an understanding of the influences of process parameters and catalysts on the process. Objectives of this research are as follows:1. Identify optimum H2:CO ratio for targeted end use applications.2. Investigation of the influence of steam and CO2 reaction atmospheres on the pyrolysis-catalytic reforming of MSW and its components towards targeted H2:CO ratios.3. Investigation of the influence of catalyst type for the steam/CO2 reforming of MSW and its components possessing with the aim of producing catalysts with high catalytic activity and stability in relation to syngas production and reduced carbon formation to maximise hydrogen and carbon monoxide production.4. Investigation of the optimum process parameter to maximise H2 and CO in the syngas production from the steam/CO2 reforming of MSW pyrolysis gases e.g. catalyst temperature, catalyst ratio and steam/CO2 flow rate.5. Investigation of additional stage(s) in the process to maximise H2 and CO in the syngas production e.g. via CO2 capture or steam/CO2 addition.