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Kinetic, isothermal and thermodynamic studies for the oil spills removal process have been conducted by Chitosan and novel amphiphilic Chitosan-g-Octanal Schiff base adsorbents developed by click chemistry and evaluated successfully in the removal of heavy crude oil spills. Chitosan was first prepared from wastes of marine shrimp shells, and then Chitosan and Chitosan-g-Octanal Schiff base adsorbents were synthesized and verified their structures, thermal stability and their morphological changes using FT-IR spectroscopy, TGA and SEM. The oil adsorption percentages (%) using heavy crude oil were 96.41% for the Chitosan-g-Octanal Schiff base adsorbent compared to 64.99% for native Chitosan counterpart. High rate of adsorption was observed where 40% of oil adsorbed within 15 min only using the Chitosan-g-Octanal Schiff base adsorbent compared to 90 min for native Chitosan adsorbent. The adsorption process followed the pseudo-second order model, and the equilibrium data were sufficiently fitted with the Langmuir model with a maximum adsorption capacity 30.30 g/g at 25 °C. Thermodynamic parameters computed from Van't Hoff plot confirmed the process to be endothermic, favorable and spontaneous. [ABSTRACT FROM AUTHOR]

A novel chitosan grafted citronellal (Ch-Cit) schiff base amphiphilic polymer was developed for the adsorptive removal of oil spills. The chemical structure was verified by FT-IR spectroscopy and 1H NMR spectrometer, while the morphological changes and surface area were investigated by SEM and BET analysis tools. The amphiphilic character of Ch-Cit schiff base was controlled through variation of the grafting percentage (G%) of citronellal from 11 to 61%. Dramatic changes in the ion exchange capacity (IEC), solubility and water uptake profiles were established, while the oil adsorption capacity was founded in direct relation with the G (%) of citronellal. Operational conditions such as oil amount, adsorption time, adsorbent dose and agitation speed were investigated. The developed Ch-Cit schiff base exhibited a higher surface area (115.94 m2/g) compared to neat chitosan (57.78 m2/g). The oil adsorption capacity of the Ch-Cit schiff base was greatly improved by 166% and 120% for light crude and heavy crude oil, respectively. Finally, the adsorption process was optimized using response surface methodology (RSM).The results substantiate that the amphiphilic Ch-Cit schiff base could be efficiently applied as a low-cost oil-adsorbent for the removal of crude oil spills from sea-water surfaces. [ABSTRACT FROM AUTHOR]

In this study, the sorption of oil from seawater using chitosan grafted poly(butyl acrylate) copolymer was optimized using response surface methodology (RSM). The effect of various parameters such as time, initial oil concentration, temperature, sorbent dose, and agitation rate on the oil sorption capacity was investigated. Plackett-Burman design was utilized for screening the various sorption parameters. RSM was adopted to acquire the best sorption conditions of two chitosan derivatives namely; CS-g-poly(ButA10) and CS-g-poly(ButA20). In this respect, the Box-Behnken design was applied. A second-order-polynomial model indicated that the sorption was very useful and able to achieve highest sorption capacity ranged from 79.56 to 92.29 g/g using grafted chitosan derivatives compared to 35.2 g/g for native chitosan in 180 min, 41.23-50 g/L of oil concentration, 38°C-41°C at 155-160 rpm. These findings nominate the fabricated CS-g-poly(ButA10) sorbent as an effectual and promising oil sorbent for environmental control of crude heavy oil spills. [ABSTRACT FROM AUTHOR]