Water-soluble chitosan from shrimp and mussel shells as corrosion inhibitor on tinplate in 2% NaCl

Abstract

Water-Soluble Chitosan (WSC) was synthesized from shrimp and mussel shells and used as corrosion inhibitor on tinplate in NaCl 2%. Chitin was extracted from shrimp and mussel shells by demineralization and deproteinization reactions.Chitin was deacetylated to obtain crude chitosan. WSC was obtained by depolymerization reaction of the crude chitosan using H2O2. WSC performance as corrosion inhibitor on tinplate in NaCl 2% was studied by weight loss and potentiodynamic polarization methods. WSC inhibition efficiency was studied in various concentrations in the range of 10-1500 mg/L. Maximum inhibition efficiencies of WSC from shrimp shells waste were 72.73% (weight loss method) and 91.41% (potentiodynamic polarization method), while maximum inhibition efficiency of WSC from mussel shells waste was 54.55% (weight loss method) with the addition of 1300 mg/L WSC concentration. Weight loss studies revealed that WSC acted as mixed type of inhibitor and obeyed Freundlich adsorption isoterm.