Utilization of chitosan extracted from shrimp shell waste in wastewater treatment as low cost biosorbent

Abstract

Chitin, which is the second most abundant biopolymer next to cellulose, and can be extracted commercially from the shells of crustacean (such as crabs, shrimps, prawns, krill), insects, fungi, and yeast. It can be converted into chitosan by partially deacetylation process. chitosan, has unique and distinctive features like, biodegradability, nontoxicity, high reactivity, excellent chelation behavior due to the presence of amine and hydroxyl functional groups which show high adsorption potential for various aquatic pollutions, and low cost in comparison with other adsorbents. Chitosan was successfully produced in the laboratory from shell waste. The yield was about 42.34 gm dry chitosan with ratio of 15.3% from the dry shells. The produced chitosan has good solubility in 1% acetic acid solution, it achieved up to 96.3%. It has % D.D.A. with value of 63% to 80%. However, it has good performance in removal of metals from industrial wastewater, it is not recommended to use it in the raw form due to presence of undesirable characters; such as low mechanical strength, swelling, and solubility in acidic media. chitosan/Activated carbon composite overcome these undesirable features in chitosan and gave good performance in the remediation of wastewater.