Hydrogenation and Liquefaction of Waste Plastics through Partical Oxidation and Water Gas Shift Reaction in Supercritical Water

开发了废塑料在超临界水中通过部分氧化和水煤气变换反应进行加氢处理的工艺。在本研究中，为了开发该工艺，我们对关键反应进行了基础研究，即1)烃的热解，2)烃的部分氧化，3)超临界水中的部分氧化加氢和水煤气变换(WGS)反应。1)烃类-超临界水体系相平衡的测定我们研制了测定烃类-超临界水体系相平衡的新型装置(高温高压振动密度测量仪)。2)利用间歇反应器进行了烃类在超临界水中的裂解实验。结果表明，随着水密度的增加，L-烷烃/烯烃比增大，产物分布向较短链烃转移。Thi…3)超临界水中烃类部分氧化反应研究。在间歇式反应器中进行了正十六烷在超临界水中部分氧化的实验研究。结果表明，随着水密度的增加，催化剂对CO和正构烷烃生成的选择性增强。正构烷烃选择性的提高表明，生成的CO与水反应生成H2，然后由L烷烃加氢生成正构烷烃。我们还在流动装置上进行了超临界水中甲烷部分氧化的实验。CO的选择性随水密度的增加而增加。采用甲烷气相氧化常用的自由基网络模型来描述超临界水中甲烷的部分氧化反应。考虑水密度效应对生成H_2O_2的基元反应进行修正，可以用模型描述超临界水中甲烷部分氧化的反应速率和产物分布。4)连续过程的设计在上述实验结果的基础上，我们对烃类部分氧化的连续过程进行了可行性研究。结果表明：a)烃的进料浓度应大于10%，b)氧浓度应在15%左右，c)氧的液相进料较佳，上述结果表明超临界水中部分氧化催化加氢和水煤气变换反应具有较高的加氢潜力。较少

We have developed a hydrogenation process of waste plastics through partial oxidation and water gas shift reaction in supercritical water. In this research, for the development of the process, we conducted the basic study of the key reactions, namely 1) pyrolysis of hydrocarbon, 2) partial oxidation of hydrocarbon, and 3) hydrogenation through partial oxidation and water gas shift (WGS) reaction in supercritical water. The results are as follows.1) Measurement of phase equilibria of hydrocarbon - supercritical water systemWe have developed the new equipment (vibrational density measurement apparatus for high temperature and pressure) to measure the phase equilibria of hydrocarbon - supercritical water system.2) Pyrolysis of hydrocarbon in supercritical waterPolyethylene pyrolysis experiments were conducted by using batch reactors. The results showed that l-alkane/alkene ratio increased and product distribution shifted toward shorter chain hydrocarbons with increasing water density. Thi … More s result can be explained by considering change of the reaction phase with water density.3) Study on hydrogenation of hydrocarbons through partial oxidation in supercritical water.The experiments of partial oxidation of n-hexadecane in supercritical water were conducted by batch reactors. In the results, the selectivities of CO and n-alkane formation were enhanced with increasing water density. The increase in n-alkane selectivity indicates that the produced CO reacted with water to produce H2 followed by the hydrogenation of l-alkane to n-alkane.We also conducted the experiments of partial oxidation of CH4 in supercritical water using a flow apparatus. The selectivity of CO increased with increasing water density. We applied a radical network model, which is commonly used for the gas-phase oxidation of CH4, for describing the partial oxidation of CH4 in supercritical water. Modifying the elementary reactions of forming H2O2 with considering the water density effect, we could described the reaction rate and the product distribution of the partial oxidation of CH4 in supercritical water by model.4) Designs of a continuous processWe made a feasibility study for a continuous process of partial oxidation of hydrocarbon based on the above experimental results. The results suggest that a) the feed concentration of hydrocarbon should be higher than 10%, b) oxygen concentration should be around 15%, and c) liquid phase feeding of oxygen is preferable.The above results suggest that catalytic hydrogenation through partial oxidation and water gas shift reaction in supercritical water have a high potential for hydrogenation of hydrocarbons. Less