摘要:
关键词: 硝酸催化还原 / 合成气制乙二醇 / 亚硝酸甲酯
Abstract: Given the situation of domestic syngas-to-ethylene-glycol process lines, the simultaneous existence of such nitrogen oxides as NO、NO2, N2O3 and N2O4 and water in the reaction systems, and the inevitable production of nitrate and nitrite, the methods of dealing with dilute nitric acid in the reaction liquid and the reaction principles and process of nitric acid catalytic reduction technology in the methanol solution with dilute nitric acid are analyzed, and measures enabling dilute nitric acid in the methanol solution to react in the presence of a catalyst with nitrogen oxides in the syngas are taken. The results of application in the 200,000 t/a syngas-to-ethylene-glycol unit of Puyang Yongjin Chemical Co., Ltd. are specifically as follows: dilute nitric acid in the reaction liquid is converted via catalytic reduction reaction into methyl nitrite needed for production, reducing the consumptions of such needed chemicals as dilute nitric acid, sodium nitrite, and caustic soda by about 90%, and thus saving production cost, and effectively decreasing the quantity of waste water containing high-concentration salt in the process of making or supplementing methyl nitrite, and correspondingly lowering the difficulty of wastewater treatment in the syngas-to-ethylene-glycol unit.
Keywords: catalytic reduction of nitric acid / syngas to ethylene glycol / methyl nitrite
针对国内现有合成气制乙二醇的工艺路线以及在反应体系中同时存在 NO、NO2、N2O3及N2O4等多种氮氧化物和水，不可避免地生成硝酸及亚硝酸的情况，分析了反应液中稀硝酸的处理方法和硝酸催化还原技术对含有稀硝酸的甲醇溶液的反应原理和流程，采取了使甲醇溶液中的稀硝酸在催化剂作用下与合成气中的氢氧化物反应并利用的措施，结果表明，在濮阳永金化工有限公司 20 万t/a装置上的应用,催化还原将反应液中的稀硝酸反应生成生产所需的亚硝酸甲酯，降低了生产过程中所需的稀硝酸、亚硝酸钠、烧碱等化学品的消耗约 90%，节约了生产成本，还有效减少了合成气制乙二醇装置处理因制备补充亚硝酸甲酯而产生的高浓度含盐废水的难度。
关键词: 硝酸催化还原 / 合成气制乙二醇 / 亚硝酸甲酯
Abstract: Given the situation of domestic syngas-to-ethylene-glycol process lines, the simultaneous existence of such nitrogen oxides as NO、NO2, N2O3 and N2O4 and water in the reaction systems, and the inevitable production of nitrate and nitrite, the methods of dealing with dilute nitric acid in the reaction liquid and the reaction principles and process of nitric acid catalytic reduction technology in the methanol solution with dilute nitric acid are analyzed, and measures enabling dilute nitric acid in the methanol solution to react in the presence of a catalyst with nitrogen oxides in the syngas are taken. The results of application in the 200,000 t/a syngas-to-ethylene-glycol unit of Puyang Yongjin Chemical Co., Ltd. are specifically as follows: dilute nitric acid in the reaction liquid is converted via catalytic reduction reaction into methyl nitrite needed for production, reducing the consumptions of such needed chemicals as dilute nitric acid, sodium nitrite, and caustic soda by about 90%, and thus saving production cost, and effectively decreasing the quantity of waste water containing high-concentration salt in the process of making or supplementing methyl nitrite, and correspondingly lowering the difficulty of wastewater treatment in the syngas-to-ethylene-glycol unit.
Keywords: catalytic reduction of nitric acid / syngas to ethylene glycol / methyl nitrite