Toteva V.Stanulov K.Shishkova I.Stratiev D.2024-07-162024-07-162024-07-162024-07-162020-01-011314-79781314-7471SCOPUS_ID:85100617552https://rlib.uctm.edu/handle/123456789/1303The investigation of production and application of environmentally friendly fuels has intensified because of the legislation requiring an increased control of the greenhouse gas emissions. Stringent rules have been introduced to decrease the sulphur content of the liquid fuels to an ultra-low level, which in turn makes the desulphurization technologies development an important research goal. The hydrodesulphurization (HDS) is the current industrial method for fuels sulphur removal. The objective of the present study is to decrease the sulphur content of heavy gas oil by oxidation-extraction desulphurization which is one of the alternative methods which are aimed at. An adequate mathematical model is developed on the ground of a planned experiment approach which describes the effect of a number of factors (a temperature, contact time, and a peroxide-to-formic acid molar ratio) on the rate of sulphur content decrease. The optimal values of the variables are found to provide sulphur decrease in the heavy gas oil raffinates of up to 87 %. The process is monitored by FTIR and NMR spectroscopy, and gas chromatography equipped with sulphur chemiluminescence detector (SCD).enArticle