Hydrophobic Coatings for Corrosion Control of Aluminum Heat Exchangers

Abstract

The production of thin films (nanocoatings) is a technological field with many applications to elaborate materials with new properties to be used as corrosion protection of traditional metals. Hydrophobicity is an example of such properties. In this chapter, an example of two hydrophobic corrosion coatings for possible use over aluminum heat exchanger geothermal power plants is discussed. Material substrate preparation, synthesis of hydrophobic sol-gel nanocoating, characterization, and electrochemical evaluation as a function of time of immersion, which are compared to another commercial fluorinated compound, are presented. Good corrosion protection was found for both hydrophobic coatings for possible application in geothermal heat exchangers.

Research and Development on Coatings and Paints for Geothermal Environments: A Review

“…A commercial fluoride compound tetra deca‐flouro hexane paint (TDFH, Chemguard, Sigma–Aldrich) was also prepared by Covelo et al. [ 93 ] by sol–gel synthesis and spin‐coating deposition to enhance hydrophobicity and corrosion protection to aluminum heat exchangers. Different paint samples were prepared by varying the proportions of the TDFH compound incorporated during sol‐gel synthesis (10%, 20%, and 30%).…”

“…Two paint systems, perfluoro ethyl trioxisylane {CF 3 (CF 2 ) 5 (CH 2 ) 2 ‐Si(OCH 2 CH 3 ) 3 } (PTES) deposited by dip technique and 3‐glycyloxypropyltrimethoxysilane (GPTMS), deposited by spin‐coating were tested by Covelo et al. [ 93 ] for hydrophobicity and corrosion resistance improvement for aluminum heat exchangers. The paints were tested alongside a commercial fluoride compound tetra deca‐flouro hexane paint (TDFH, Chemguard, Sigma‐Aldrich) paint deposited by spin‐coating.…”

“…Two paint systems, perfluoro ethyl trioxisylane {CF 3 (CF 2 ) 5 (CH 2 ) 2 -Si(OCH 2 CH 3 ) 3 } (PTES) deposited by dip technique and 3-glycyloxypropyltrimethoxysilane (GPTMS), deposited by spin-coating were tested by Covelo et al [93] for hydrophobicity and corrosion resistance improvement for 1. Reproduced with permission.…”