Chitosan/Lignosulfonate Nanospheres as "Green" Biocide for Controlling the Microbiologically Influenced Corrosion of Carbon Steel.

Pathath Abdul Rasheed,Khaled A. Mahmoud,Ayman Samara,Ravi P. Pandey,Khadeeja A. Jabbar,Aboubakr M. Abdullah

doi:10.3390/ma13112484

Abstract

In this work, uniform cross-linked chitosan/lignosulfonate (CS/LS) nanospheres with an average diameter of 150–200 nm have been successfully used as a novel, environmentally friendly biocide for the inhibition of mixed sulfate-reducing bacteria (SRB) culture, thereby controlling microbiologically influenced corrosion (MIC) on carbon steel. It was found that 500 µg·mL−1 of the CS/LS nanospheres can be used efficiently for the inhibition of SRB-induced corrosion up to a maximum of 85% indicated by a two fold increase of charge transfer resistance (Rct) on the carbon steel coupons. The hydrophilic surface of CS/LS can readily bind to the negatively charged bacterial surfaces and thereby leads to the inactivation or damage of bacterial cells. In addition, the film formation ability of chitosan on the coupon surface may have formed a protective layer to prevent the biofilm formation by hindering the initial bacterial attachment, thus leading to the reduction of corrosion.

Highlights

Influenced corrosion (MIC) of carbon steel is a major cause of metal corrosion and pipeline failure [1,2,3]
The uniform CS/LS nanospheres have been prepared by one-step covalent cross-linking between chitosan (CS) and lignosulfonate (LS) according to our reported method [31]
Image (Figure 1A), well-dispersed spherical nanoparticles were obtained with an average diameter of 150–200 nm

Summary

Introduction

Influenced corrosion (MIC) of carbon steel is a major cause of metal corrosion and pipeline failure [1,2,3]. It is estimated that MIC accounts for about 20% of the corrosion damage in the oil and gas sector [4]. Despite the tremendous efforts made far to improve corrosion management, MIC has remained a pressing issue for the oil/gas sector, where there is exposure of metals to bacteria found in water. Several types of microorganism are responsible for MIC, including sulfate-reducing bacteria (SRB), iron-oxidizing bacteria (IOB), slime-forming bacteria, and iron-reducing bacteria (IRB). SRB are the main microorganisms responsible for MIC by generating sulfide species anaerobically, which causes progressive biocorrosion in the water transport systems [5,6]. The SRB strains produce hydrogen sulfides (H2 S), metal sulfides, and sulfates as a result of biogenic oxidation/reduction reactions [7,8]. The production of H2 S at elevated concentrations creates intrinsic heterogeneity, which accelerates the corrosion process by favoring electrochemical reactions [9,10,11]

Methods

Results

Conclusion