Evaluation of poly-beta-hydroxybutyrate as a sorbent material for the removal of spilled crude oil from water

摘要

Oil spills in the ocean are becoming an increasingly serious problem and the search for an adsorption material that is effective and environmentally safe is a popular research topic. This study presents a sorbent micro-ball composed of poly-beta-hydroxybutyrate. Field emission scanning electron microscopy was used to observe morphology of the micro-ball. Additionally, Fourier transform infrared spectroscopy was used to analyze the surface groups, and nitrogen adsorption was used to determine specific surface area and pore size distribution. The effects of such conditions as initial oil concentration, temperature, pH, and water salinity on the adsorption efficiency were studied. The results show that the equilibration time is 60min. The adsorption isotherm experiments indicate that the Freundlich model fits the experimental data better than the Langmuir and Henry models, and the adsorption kinetics experimental results show that the pseudo-second-order model fits the experimental data well. The adsorption capacity is proportional to the initial oil concentration. The removal rate increases as the temperature increases, and the adsorption efficacy is highest at a temperature of 25 degrees C. The adsorption capacity varies directly with pH value. Finally, the adsorption capacity of micro-balls increases with increasing seawater salinity.