Sliuzar A. Theoretical basis and technologies of oxygen-free gases purification from hydrogen sulfide by quinhydrone method

The dissertation aims to develop theoretical foundations and technologies for the purification of oxygen-free gases from hydrogen sulfide by quinhydrone oxidizing systems (QOS) to increase their technological and technical and economic efficiency. This makes it possible to solve an important scientific and technical problem that is relevant for the gas, oil refining, coke and chemical industries, agriculture, and utilities. The object of research is liquid-phase oxidative processes of purification of oxygen-free (natural and technological) gases from H2S by QOS. The subject of the study is the chemisorption of hydrogen sulfide from gases by quinhydrone absorption solution (QAS); chemisorption of oxygen from the air by QAS; regularities of obtaining QOS; electrochemical regeneration of QOS; mass transfer equipment for the gas-liquid system; physicochemical laws and mathematical dependences that describe the processes of chemisorption of gases; the influence of technological parameters on the efficiency and selectivity of these processes. Research methods: cyclic voltammetry, redox and pH potentiometry, volume analysis, IR, UV and visible spectroscopy, scanning electron microscopy, experimental verification of the developed mathematical models and technologies of gases purification from hydrogen sulfide on laboratory and the large-scale laboratory installations with the use of physical models of the main devices. Among the important scientific results are: expanded knowledge of the physicochemical properties of QAS at high concentrations of components; the choice of rational mass transfer equipment for chemisorption of H2S from oxygen-free gases and O2 from air with these solutions is substantiated; an improved method of QOC preparation is proposed to increase the efficiency of gas purification and the selectivity of targeted oxidation of chemisorbed H2S to S or Na2S2O3; for the first time the regularities of phase equilibrium in the system of hydrogen sulfide - QAS; the mathematical dependence of the equilibrium partial pressure of hydrogen sulfide on the composition of the QAS is derived; technological bases of two-stage purification of gases from hydrogen sulfide by quinhydrone method are developed; developed and experimentally tested a mathematical model of the process of chemisorption of H2S from oxygen-free gases of QAS in the bubbling apparatus; developed a mathematical model of the process of chemisorption of O2 from the air during the regeneration of QAS and established the kinetic parameters of this process in the absorber with a continuous bubbling layer; acquired further development of knowledge about the laws of mass transfer processes in the horizontal absorber with bucket-shaped dispersants (HABD); for the first time the influence of oxygen-free gas components on gases purification from H2S by QAS and its regeneration was studied, which allowed to practically unify technological schemes of purification of different natural and technological gases; for the first time the basic laws of electrochemical regeneration of QAS are established. Based on these scientific data, variants of technological schemes for purification of natural and various process gases from H2S with the production of fine sulfur and the possibility of combining these technologies with polymeric sulfur technology, which increases the economic efficiency of the quinhydrone desulfurization process. The technologies of pyrolysis gas purification of olefin production at LLC "Karpatnaftochim" and purification of hydrocarbon gas of the delayed coking plant at PJSC "Naftokhimik Prykarpattya" were proposed for industrial implementation.