USE OF PYROLYSIS DISTILLATE RAW MATERIALS FOR OBTAINING BENZENE

Аннотация

The process of obtaining benzene and its homologues based on pyrolysis distillation has been implemented, the quantitative and qualitative composition of pyrolysis distillate samples and the processing of their fractions have been studied. Qualitative analysis was carried out by IR spectroscopic method, quantitative composition was studied by gas chromatograph with mass spectroscopy. KEYWORDS Pyrolysis distillate, benzene, toluene, xylene, methylethylbenzene, propylbenzene qualitative and quantitative analysis. INTRODUCTION requirements of modern technology. Therefore, the search and study of the extracting properties of In the Republic of Uzbekistan, the presence and effective polar solvents for the production of benzene expansion of pyrolysis production makes it possible to in Uzbekistan is an extremely important and urgent produce pyrolysis benzene by pyrolysis of gas national economic task. condensate and catalytic reforming of oil products, followed by extraction separation of catalysts and Benzene is the most important raw material of the pyrocondensates with selective solvents [2]. petrochemical industry, on the basis of which large- scale organic synthesis products are produced. To date, universal extractants have not yet been found According to Rosstat, the volume of benzene that combine high separation selectivity with a production (including from pyrolysis products and sufficiently high dissolving ability and fully meet the petroleum) amounted to 1,200 thousand tons. Volume 03 Issue 11-2023 188 International Journal of Pedagogics (ISSN – 2771-2281) VOLUME 03 ISSUE 11 PAGES: 188-194 SJIF IMPACT FACTOR (2021: 5. 705) (2022: 5. 705) (2023: 6. 676) OCLC – 1121105677 Publisher: Oscar Publishing Services Servi According to experts from the Industrial Information has a number of disadvantages. Therefore, research is Agency, global demand for benzene will grow by an widely carried out in the field of synthesis of new average of 5.2% per year and will amount to 41 million effective solvents and improvement of technology tons. The fastest growth will be observed in Asia based on existing extractants [5-9]. (excluding Japan) - an average of 7.5% per year - and in The most common extractant for C6 – C8 aromatic other regions of the world - 13.6% (mainly in the Middle hydrocarbons is diethylene glycol, used in the Judex East and South America). The main increase in benzene process [5,6,7]. Its widespread use is explained by its production volumes will occur due to the introduction high selectivity, comparative cheapness, availability, of new capacities, as well as due to an increase in the high thermal stability and low toxicity. Diethylene production of pyrolysis benzene [1]. glycol provides high recovery and purity of aromatic In different countries, the production of benzene is hydrocarbons. The Yudex process has been intensively based on different processes. The main sources of improved by improving technology and replacing benzene production in Uzbekistan are pyrolysis diethylene glycol with higher polyglycols - tri- and distillate produced by Uz-Kor Gas Chemical LLC JV and tetraethylene glycol, which have greater capacity reforming catalyst produced by Bukhara Oil Refinery compared to diethylene glycol and almost the same LLC. selectivity [2, 3, 4]. One of the main points affecting the efficiency of the Sulfolane is one of the most effective modern selective extraction process is the efficiency of the extractant, solvents, as evidenced by the rapid introduction of the which determines the ratio of solvent to raw material. sulfolane process into industry abroad. So, if the first Reducing this ratio is one of the promising ways to installation was launched in 1962, then in 1970 the improve the technical and economic indicators of the process was already used in 40 installations. process. Disadvantages of the process include difficulties in removing solvent from separation products and the The literature [2,4] describes in detail the requirements need to use reduced pressure when regenerating the for selective solvents. An industrial extractant must solvent. Sulfolane has a relatively high melting point have high selectivity and dissolving ability, easy (27.8°C) [l0], which can be reduced by adding water, regenerability, a sufficiently high density difference but this leads to a significant decrease in the solubility with the raw materials being separated, low viscosity, of sulfolane. Dramatic changes in process conditions etc. When selecting an extractant, consideration compared to the Yudex process and the relatively high should be given to solvent resources and the ability of cost of sulfolane require significant investment. the selected solvent to be used beyond extraction processes and for other industrial purposes. Currently, The French Petroleum Institute proposed using more than 200 solvents have been proposed for the dimethyl sulfoxide as an extractant. Its main extraction of aromatic hydrocarbons