Systematic multivariate optimisation of butylene carbonate synthesis via CO2 utilisation using graphene-inorganic nanocomposite catalysts

Abstract

The synthesis of butylene carbonate (BC) through the reaction of butylene oxide (BO) and carbon dioxide (CO2) has been investigated using highly efficient graphene-inorganic heterogeneous catalyst, cerium-lanthana-zirconia and graphene oxide represented as Ce–La–Zr–GO nanocomposite. The systematic multivariate optimisation of BC synthesis via CO2 utilisation using graphene-inorganic nanocomposite has been developed using Box-Behnken Design (BBD) of Response Surface Methodology (RSM). The BBD has been applied to optimise the single and interactive effect of four independent reaction variables, i.e. reaction temperature, pressure, catalyst loading and reaction time on the conversion of BO and BC yield. Two quadratic regression models have been developed representing an empirical relationship between each reaction response and all the independent variables. The predicted models have been validated statistically and experimentally, where a high agreement has been observed between predicted and experimental results with approximate relative errors of ±1.45% and ±1.52% for both the BO conversion and BC yield, respectively. The implementation of RSM optimisation process for the conversion of BC through the reaction between BO and CO2, has offered a new direction in green chemical process in terms of waste reduction, maximising production of value-added chemicals and effectively utilise CO2 gas emissions.