Adsorptive removal of crude petroleum oil from water using floating pinewood biochar decorated with coconut oil-derived fatty acids

The present investigation deals with the adsorptive removal of crude petroleum oil from the water surface using coconut oil-modified pinewood biochar. Biochar generated at higher pyrolysis temperature (700 degrees C) revealed higher fatty acid-binding efficiency responsible for the excellent hydrophobicity of the biochar. Fatty acids composition attached to the biochar produced at 700 degrees C was (mg g(-1) BC) lauric acid (9.024), myristic acid (5.065), palmitic acid (2.769), capric acid (1.639), oleic acid (1.362), stearic acid (1.114), and linoleic acid (0.130). Simulation of the experimental adsorption data of pristine and modified pinewood biochar generated at 700 degrees C offered the best fit to pseudo-first-order kinetics (R-2 > 0.97) and Langmuir isotherm model (R-2 > 0.99) based on the highest regression coefficients. Consequently, the adsorption process was mainly driven by surface hydrophobic interactions including pi-pi electron-donor-acceptor between electron-rich (pi-donor) polycyclic aromatic hydrocarbons from the crude oil and biochar (pi-acceptor). A maximum adsorption capacity (Qmax) of 5.315 g g(-1) was achieved by modified floating biochar within 60 min. Whereas the reusability testing revealed 49.39% and 51.40% was the adsorption efficiency of pristine and modified biochar at the fifth adsorption-desorption cycle. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The study focused on the adsorptive removal of crude petroleum oil from water surface using coconut oil-modified pinewood biochar, which showed excellent adsorption efficiency and hydrophobicity. Experimental data simulation indicated that the modified biochar generated at 700 degrees C exhibited the best fit with pseudo-first-order kinetics and Langmuir isotherm model, suggesting that the adsorption process was mainly driven by surface hydrophobic interactions.