Abstract
Matrix acidizing of oil and gas reservoirs is a widely established technique to increase hydrocarbon production. Strong mineral acids such as HCl or HCl/HF mixtures are injected into the well at high concentrations. For this application, corrosion inhibitors are enabling because uninhibited matrix acidizing treatment fluids would induce severe corrosion of downhole equipment. A broad range of organic film-forming corrosion inhibitors have been developed to retard the acid corrosion of coiled tubing and casing through which the acidizing fluids are injected. In this paper, the corrosion inhibition of polymerizable organic corrosion inhibitors for a coiled tubing low carbon steel, medium carbon steel, high alloy (UNS S42000) and Duplex (UNS S32205) casing steels in 4M hydrochloric acid solution at 800C was investigated by weight loss technique. This paper summarizes structure-property relationships for various polymerizable organic corrosion inhibitors, including acetylenic alcohols and derivatives of cinnamic acid, i.e. trans-cinnamaldehyde and cinnamonitrile. The influence of metal composition on the efficiency of film forming corrosion inhibitors and the synergetic behavior with quaternary ammonium cations is discussed.
