Isotherm and kinetic studies on adsorption of gasoline and kerosene using jujube and barberry tree stem powder and commercially available activated carbon.

ABSTRACT

Herein, the application of granular activated carbon, jujube, and barberry tree stem powder for the removal of gasoline and kerosene from water was investigated. Kerosene removal rates upwards of 68.48, 83.87, and 99.02% were achieved using jujube tree stem powder, barberry tree stem powder, and granular activated carbon, respectively. Besides, gasoline removal rates upwards of 69.35, 55.02, and 95.59% were attained using jujube tree stem powder, barberry tree stem powder, and granular activated carbon, respectively. Isotherm data were further investigated and fitted using Langmuir, Freundlich, and Elovich models. The results indicated that the adsorption onto jujube adsorbent is a multilayer adsorption process over a heterogeneous surface, which is best illustrated by the Temkin (Ave. R2= 0.95) model. It was found that the Temkin isotherm (Ave. R2= 0.81) best describes the properties of barberry stem powder in the adsorption of gasoline and kerosene from water. Moreover, the best models to describe the characteristics of granular activated carbon in the adsorption of gasoline and kerosene from water were Freundlich (Ave. R2= 0.74) and Langmuir (Ave. R2= 0.73) isotherms, respectively. The adsorption kinetics showed that the pseudo-second-order was appropriate in modeling the adsorption kinetics of gasoline and kerosene to the studied adsorbents (R2>0.74).

The objective of this study was to identify the potential of agricultural biowastes derived biosorbents to remove petroleum products from contaminated water. Previously, jujube and barberry tree wastes had not been used to remove petroleum pollutants. Moreover, in this research agricultural wastes were used without any processing or energy consumption and all experiments were performed at water pH, so there was no need to add chemicals to adjust the pH.