Effect of diesel on corrosion inhibitors and application of bio-enzyme corrosion inhibitors in the laboratory cooling water system

Negative effects of diesel on corrosion inhibition performances of 1-hydroxy ethylidene-1, 1-diphosphonic acid (HEDP), amino trimethylene phosphonic acid (ATMP), lysozyme and laccase were investigated. Orthogonal array design (OAD) was used for achieving the optimal composition of a combined inhibitor. The applied conditions of the combined inhibitor were also optimized. The results show that diesel can badly affect corrosion inhibition performances of HEDP, ATMP, lysozyme and laccase. The optimal combined inhibitor consisting of 30 mg/L ATMP, 30 mg/L lysozyme and 40 mg/L laccase can make the corrosion rate of carbon steel below 0.0075 mm/y and the corrosion inhibition efficiency above 96%. (C) 2015 Elsevier Ltd. All rights reserved.