双氧水装置工作液双氧水体系爆炸机理研究

发布时间：2018-09-03 11:27

【摘要】：过氧化氢是世界主要的基础化学产品之一。目前国内过氧化氢生产工艺主要采用蒽醌法,经氢化、氧化、萃取、纯化及浓缩制得不同浓度的过氧化氢水溶液。在萃取过程中,当萃取塔中过氧化氢超过一定浓度后,会与工作液形成多元非均相体系,有爆炸风险,大大制约了直接萃取得到高浓度过氧化氢工艺的发展。进行萃取塔中过氧化氢-工作液体系爆炸反应研究对蒽醌法工艺安全及萃取工艺优化具有重要意义。本文以中石化河北某炼化双氧水中试装置为研究对象,研究萃取塔中工作液双氧水体系爆炸规律。为简化多元体系,研究了过氧化氢-磷酸三辛酯-三甲苯三元体系的爆炸规律,并确定工作液中单一组分对体系爆炸规律的影响。研究发现三甲苯双氧水体系在双氧水浓度大于59%之后进入爆炸区间。加入表面活性剂之后,浓度高于46.3%后进入爆炸区间。磷酸三辛酯双氧水体系中,双氧水浓度大于42.9%进入爆炸区间。工作液双氧水体系未加表面活性剂时双氧水浓度高于46.7%已经进入了爆炸范围,并且随着过氧化氢浓度升高,体系的爆炸范围在扩大。加入表面活性剂后,双氧水浓度高于42.3%时,进入爆炸区间。在上述爆炸实验基础上,对过氧化氢-三甲苯体系爆炸产物进行收集、分析,推测体系爆炸反应机理。采用密度泛函理论方法,运用量子化学软件,首先对过氧化氢自分解反应机理中每一步基元反应的过渡态进行计算,通过频率分析及IRC验证了过渡态存在的真实性,并且计算了分解反应焓变。然后采用同样方法对过氧化氢-三甲苯初步反应机理进行模拟研究,通过分子模拟以及电子云分布和电荷分布分析,得到了三甲苯-过氧化氢爆炸反应初期的反应过程。通过在分子尺度上对过氧化氢分解及过氧化氢-三甲苯体系反应机理进行分析研究,为高浓度过氧化氢安全生产和使用提供依据和指导。
[Abstract]:Hydrogen peroxide is one of the main basic chemical products in the world. At present, hydrogen peroxide aqueous solution with different concentration is prepared by hydrogen peroxide production process by hydrogenation, oxidation, extraction, purification and concentration. In the process of extraction, when the concentration of hydrogen peroxide in the extraction column exceeds a certain concentration, a multicomponent heterogeneous system will be formed with the working liquid, which has the risk of explosion, which greatly restricts the development of the process of direct extraction to obtain high concentration hydrogen peroxide. It is of great significance to study the explosion reaction of hydrogen peroxide-working liquid system in extraction column for the safety of anthraquinone process and the optimization of extraction process. In this paper, a pilot plant in Hebei Province of Sinopec was used to study the explosion law of hydrogen peroxide system in the working liquid of extraction tower. In order to simplify the multicomponent system, the explosion law of the ternary system of hydrogen peroxide, trioctyl phosphate and trimethylbenzene was studied, and the effect of a single component in the working liquid on the explosion law of the system was determined. It is found that the system of tritoluene and hydrogen peroxide enters the explosion zone after the concentration of hydrogen peroxide is greater than 59%. After the addition of surfactant, the concentration was higher than 46.3% and then entered the explosion zone. In the system of trioctyl phosphate hydrogen peroxide, the concentration of hydrogen peroxide is more than 42.9%. When the concentration of hydrogen peroxide is higher than 46.7%, the concentration of hydrogen peroxide in the system without surfactant has entered the range of explosion, and with the increase of hydrogen peroxide concentration, the explosion range of the system is expanding. After the addition of surfactant, the concentration of hydrogen peroxide was higher than 42.3 and entered the explosion zone. On the basis of the above explosion experiments, the explosive products of hydrogen peroxide-trimethylbenzene system were collected and analyzed, and the mechanism of the system explosion reaction was inferred. By using density functional theory and quantum chemical software, the transition states of each step of the radical reaction in the mechanism of hydrogen peroxide self-decomposition are calculated. The existence of the transition state is verified by frequency analysis and IRC. The enthalpy change of decomposition reaction was calculated. Then the initial reaction mechanism of hydrogen peroxide and trimethylbenzene was simulated by the same method. The initial reaction process of trimethylbenzene hydrogen peroxide explosion reaction was obtained by molecular simulation and electron cloud distribution and charge distribution analysis. The decomposition of hydrogen peroxide and the reaction mechanism of hydrogen peroxide with trimethylbenzene were studied on the molecular scale, which provided the basis and guidance for the safe production and use of high concentration hydrogen peroxide.
【学位授予单位】：青岛科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ123.6

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