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Impregnation of polyurethane foam with activated carbon for enhancing oil removal from water
Keshavarz, A.; Zilouei, H.; Abdolmaleki, A.; Asadinezhad, A. & Nikkhah, A.A.
Abstract
To enhance the oil sorption capacity of polyurethane
foam, different amounts of activated carbon (0.5,
1, 2 and 3 wt%) were grafted onto the surface of polyurethane
foam. The modified polyurethane foam was
characterized by Fourier transform infrared spectroscopy,
scanning electron microscopy, thermogravimetric analysis
and tensile elongation test. Grafting of activated carbon
improved the polyurethane foam toughness and thermal
resistance as revealed by tensile elongation and thermogravimetric
tests, respectively. Experimental results showed
the enhancement of oil sorption capacity and reduction in
the water sorption in all cases. The optimal amount of
activated carbon on the surface was 1 wt% which enhanced
the oil sorption capacity up to 33.2 %. Reusability feature
of the optimum sorbent was examined through four cycles
of chemical regeneration, and about 85 % of the initial
sorption capacity of the modified polyurethane foam was
remained at the end. Equilibrium isotherms were analyzed
using Langmuir, Freundlich and Redlich–Peterson isotherms
using linear and nonlinear regression methods. The
Marquardt’s percent standard deviation and hybrid fractional
error functions were minimized and normalized to
investigate the effect of error criteria to determine the
parameters of isotherms. The nonlinear method was found
to be more accurate to determine the isotherm parameters,
and the Langmuir isotherm was the best-fitting model.
Keywords
Adsorbent; Isotherm; Oil pollution; Reusability; Surface modification
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