Influence of Water on Noncatalytic Oxidative Desulfurization of High-Sulfur Straight-Run Oil Fractions

The noncatalytic oxidative desulfurization process of straight-run kerosene and diesel fractions with high sulfur contents due to their treatment with air without using expensive catalysts and strong oxidants is considered. The research was carried out in a periodic mode in a bubble-type reactor with a volume of 1 × 10^-3 m³ under the following conditions: 180-200 °C; 2.5-3.0 MPa; the process lasted for 20-30 min; the air/raw material ratio was 1.6-2.2 m³/min per 1 m³ of raw material. The process can be used to obtain industrial jet fuels and diesel fuel components with good lubricating properties. The possibility and expediency of carrying out the process in the presence of water have been studied. The ratio of water/raw materials (vol.) varied from 0:1 to 2:1. It was proven that the water presence in the reaction medium has a positive effect on the studied process and decreases the oxidation intensity of hydrocarbon medium by 2-4 times. This is due to both the slowing of oxidation reactions by water during peroxide decomposition and chain growth and branching and the partial change in chemical oxidation with the formation of phenols and/or tertiary alcohols, which are inhibitors of oxidation reactions. On the other hand, water has almost no effect on the removal degree of sulfur compounds.