Development of hydrotreatment technology to reduce the amount of sulfur and nitrogen in pyrolysis distillate using the TG-550 catalyst

Abstract

This article presents the results of a study on the hydrotreating process of pyrolysis distillate in an autoclave. The experiment utilized pyrolysis distillate produced at the "Uz-Kor Gas Chemical" plant, a TK-550 catalyst manufactured by "Chirchik-Maxam," and autoclave equipment. An experimental setup was assembled to study the catalytic processing of pyrolysis distillate, including an autoclave, frame, electric drive, transformer, thermoelectric heater, hydrogen cylinder, and control and measuring instruments. The optimal technological parameters for pyrolysis distillate hydrotreatment were determined: a temperature range 400–420 °C, hydrogen pressure of 4 MPa, hydrogen-containing gas circulation of 200 Nm³/m³ of feedstock, and a hydrogen concentration in the gas phase of 80 % (vol.). Elemental analysis, gas chromatography-mass spectrometry (GC-MS), and infrared (IR) spectroscopy were conducted on the hydrotreated distillate, the TG-550 catalyst was studied using SEM and X-ray diffraction analysis. As a result, the nitrogen content decreased from 7.4 wt% to 3.71 wt%, and the sulfur content was reduced from 9.24 wt% to 1.8 wt%. GC-MS spectra indicated the saturation of unsaturated bonds and a reduction in the number of aromatic rings. Fractionation of the hydrotreated product demonstrated that 58 % of the yield consisted of the fuel fraction.