Modelling and optimisation of oxidative desulphurisation of tyre-derived oil via central composite design approach

• Published in: Green processing and synthesis Vol. 8; no. 1; pp. 451 - 463
• Main Authors: Cherop, Peter Tumwet, Kiambi, Sammy Lewis, Musonge, Paul
• Format: Journal Article
• Language: English
• Published: Berlin De Gruyter 01.01.2019; Walter de Gruyter GmbH
• Subjects: Acetonitrile; Atomic emission spectroscopy; central composite design; Desulfurization; Desulfurizing; Emission analysis; Formic acid; Hydrogen peroxide; Inductively coupled plasma; Oil; Optimization; oxidative desulphurisation; Reaction time; response surface; Solvent extraction; Sulfur; Sulfur removal; tyre-derived oil; Variance analysis
• ISSN: 2191-9542; 2191-9550; 2191-9550
• DOI: 10.1515/gps-2019-0013

The aim of this study was to apply the central composite design technique to study the interaction of the amount of formic acid (6-12 mL), amount of hydrogen peroxide (6-10 mL), temperature (54-58°C) and reaction time (40-60 min) during the oxidative desulphurisation (ODS) of tyre-derived oil (TDO). The TDO was oxidised at various parametric interactions before being subjected to solvent extraction using acetonitrile. The acetonitrile to oil ratios used during the extraction were 1:1 and 1:2. The content of sulphur before and after desulphurisation was analysed using ICP-AES. The maximum sulphur removal achieved using a 1:1 acetonitrile to oxidised oil ratio was 86.05%, and this was achieved at formic acid amount, hydrogen peroxide amount, temperature and a reaction time of 9 mL, 8 mL, 54°C and 50 min respectively. Analysis of variance (ANOVA) indicated that the reduced cubic model could best predict the sulphur removal for the ODS process. Coefficient of determination (R = 0.9776), adjusted R = 0.9254, predicted R = 0.8356 all indicated that the model was significant. In addition, the p-value of lack of fit (LOF) was 0.8926, an indication of its insignificance relative to pure error.