Effects of Process Parameter on Crude Oil Biodegradation of Palm Oil Mill Effluent using Response Surface Optimization

Abstract

The aim of this study was to investigate the effects of process parameter on crude oil (CO) biodegradation of palm oil mill effluent (POME) by using response surface optimization. Physiochemical characterization of the uncontaminated soil (UCS), crude oil contaminated soils (COCS), and POME were investigated. Further characterization on the POME was done employing the scanning electron microscope (SEM) and Fourier transform infrared (FT-IR). First and second order kinetics models were used to estimate the kinetic parameters. Results obtained indicated that POME contained valuable soil nutrient as it showed a stimulatory effect on the physiochemical properties of the COCS. However, POME was able to degrade 51% of CO with an initial CO concentration of 130 g/L. The first order kinetics proved a better model with a high rate constant, lower biological half-life and R² greater than 0.96. From the optimization process, the quadratic model with 78.8% contribution and R² of 0.993 satisfactorily explained the interactions between the independent variable and the response. The FT-IR spectrum revealed the presence of nitrogen and phosphorous on the surface of POME, while SEM indicated a smooth surface of POME.