Oxidation of Sulphur pollutants in model and real fuels using hydrodynamic cavitation

•Thiophene removal using HC was effective up to fuel volume fraction of 80%•Presented influence of type and scale of HC devices on desulphurization performance.•External oxidant-catalyst is a necessary for dual-ring thiophene desulphurization.•Quantified oxidation performance of HC with stirring and AC based processing. Hydrodynamic Cavitation (HC) offers an attractive platform for intensifying oxidative desulphurization of fuels. In the first part of this work, we present new results on oxidising single ring thiophene in a model fuel over the extended range of volume fraction of organic phase from 2.5 to 80 v/v %. We also present influence of type and scale of HC device on performance of oxidative desulphurization. Further experiments revealed that oxidising radicals generated in-situ by HC alone were not able to oxidise dual ring thiophenes. External catalyst (formic acid) and oxidising agents (hydrogen peroxide, H2O2) were therefore used with HC. Based on our prior work with acoustic cavitation (AC), the volumetric ratios for H2O2 and formic acid were identified as 0.95 v/v % and 6.25 v/v % respectively. The data of oxidation of dual ring thiophenes with n-dodecane and n-hexane as model fuels and typical transport fuels (diesel, kerosene, and petrol) using these oxidant and catalyst is presented. The observed performance with HC was compared with results obtained from a stirred tank and AC set-up. The presented data indicates that HC is able to intensify oxidation of sulphur species. The presented results provide a sound basis for further developments on HC based oxidative desulphurization processes.