Synthesis and Application of Cellulose-Chitosan Sponges for the Removalof Oil Pollution and Other Organic Pollutants from Water

Extraction and transportation of crude oil led to extensive environmental effects such asleakage into the water resources [۱, ۲]. Therefore, it is very important to develop new andenvironmental friendly methods that can remove and separate these pollutants from water andeffluent with high performance [۳]. Therefore, the main objevtive of the present study wassynthesis and application of cellulose-chitosan sponges for the removal of oil pollution and otherorganic pollutants from water. In this regards, firstly cellulose was extracted from the Platanusorientalis tree leaves, then the sponges were synthesized in combination with chitosan by differentratios of ۱:۱۰, ۳:۱۰ and ۵:۱۰ (cellulose/chitosan) and the produced sponges called C۱-CH۱۰, C۳-CH۱۰, and C۵-CH۱۰ respectivly. The surface modification (hydrophobization) of the synthesizedsponge was performed by methyltrimethoxysilane vapor deposition. The structures and propertiesof the synthesised sponges were characterized by contact angle analysis (CA), SEM, N۲ sorptiondesorption,TGA, XRD and FT-IR. Finaly, fro evaluation of the sponge efficiency, the absorptionprocess was performed in a batch system on nine different petroleum and organic pollutants,including crude oil, motor oil, diesel, gasoline, liquid paraffin, hexane, chloroform, kerosene, andliquid edible oil. The CA images reviled that the water contact angle on cellulose-chitosan spongewere ۱۴۰, ۱۴۳, and ۱۴۶ degrees for C۱-CH۱۰, C۳-CH۱۰, and C۵-CH۱۰ respectivly. These valuesindicate that the hydrophobicity of sponges increased by increasing cellulose ration. The SEMimages demonstrate the porous structure of the cellulose-chitosan sponge, Which leads to anincrease in the surface-to-volume ratio and consequently an increase in the absorption capacity.Moreover, the BET analysis revealed that the specific surface area were ۳۳.۲, ۲۱.۳, and ۶۵.۳ m۲/grespectively. On the other hand, according to the BJH method the average pore size of the spongeswere ۳۶.۴۴, ۲۱.۵۷, and ۱۹.۷۱ nm, respectively. According to the absorption results, the C۱-CH۱۰sponge represent the highest absorption capacity of oil and organic pollutants and was introducedas the optimal sponge. Finally, the reusability of the sponge absorbtion was analysed, and it wasused in ۶ consecutive cycles without appreciable reduction in absorption capacity.

Keywords:

Crude oil , Organic pollutant , oil spill , absorbent , cellulose , chitosan , sponge