Remediation of crude oil-contaminated saline water using novel dispersants from fish and lobster wastes

Abstract

The use of chemical dispersants for oil spill cleanup has been reported to harm marine ecosystem due to their toxic impacts. Finding bio-based alternatives to synthesize crude oil dispersants is essential. Protein-rich food wastes were used to formulate novel dispersants to disperse crude oil spill in saline water in this study. Protein isolates were prepared from sea bass, sea bream, and lobster wastes and used to synthesize dispersants in acetic acid. Protein isolate was also prepared from a mixture of fish wastes collected from a local restaurant. Dispersants synthesized from sea bass and sea bream wastes exhibited dispersant effectiveness (DE) of about 34% (which reduces to about 26% at higher salinities). The protein isolate from sea bass and sea bream wastes exhibited smaller pore sizes and higher zeta potential. Meanwhile, dispersants synthesized from lobster or fish mix waste exhibited a DE of about 35% at all salinities. The dispersant prepared from lobster waste exhibited the highest emulsifying activity of 94.5% and the lowest foaming level of 1%. Changing the solvent to lecithin resulted in a better performance than acetic acid and the effect of dispersion time on dispersant effectiveness was the most significant, resulting in a 6-fold increase in crude oil dispersion.