Study On Synthesis And Inhibition Properties Of Pyridine Quaternary Ammonium Corrosion Inhibitors

Using corrosion inhibitors was an important method to inhibit metal corrosion. The research and application of the acidification inhibitors and sewage inhibitors used in oil exploration had been paid attention all the time. In this paper, we used kettle residues, which was generated from the production process of pyridine and alkyl pyridine by aldehydes (ketones)-ammonia crafts, to synthesis corrosion inhibitors and evaluate the inhibition performance of them.Respectively, used 3# pyridine base to react with the benzyl chloride, epichlorohydrin and allyl chloride, synthesized three kinds of pyridine single quaternary ammonium substances(respectively labeled them 3#PyBC,3#PyE and 3#PyAC). Then Used 3# pyridine base, concentrated hydrochloric acid, epichlorohydrin and dodecyl dimethyl tertiary amine, synthesized two kinds of pyridine bisquaternary ammonium substances(respectively labeled them 3#2PyE and 3#PyEDMA12). The inhibiting effect of these five kinds of pyridine quaternary ammonium substances on the corrosion of N80 steel in 15% HCl solution (60?) had been studied using weight loss measurement. The results showed that the inhibition performance of 3#PyBC was better than the other four, it is related to the adsorption of inhibitors on the surface of steel and the forming of water repellent film. Then evaluated inhibition performance of the 3#PyBC on the corrosion of N80 steel in 15% HC1 solution (90?). When the dosage of 30% 3#PyBC solution in 15% HCl solution was 0.9%, the corrosion rate of N80 steel was 2.60 g/(m2-h), met the requirements of the first level of the related evaluation criteria.To the organochlorine problem of oilfield, the experimental idea had been improved and expanded. At first,3# pyridine base was connected a period of propylene oxide segments or butadiene monoxide segments, accessed hydrophobic segments would facilitate the forming of water repellent film to resist the movement of the related substances or charge. Then accessed epoxyethane to carry out ethoxylation for improving their water solubility. In this way, we synthesised two types products (labeled them 3# PyPE products and 3# PyBE products). The products were formulated as 30% solution and added to the 15% HCl respectively. The acidification inhibition effect of them had been studied by weight loss measurement. For 3# PyPE products, when the mass ratio of 3# pyridine base, propylene oxide and epoxyethane was 1:1.6:2.4, the inhibition effect of the synthesized product (3#PyPE 136) was better, when the dosage in corrosive media(60?) was 0.5%, the corrosion rate of N80 steel was 2.57 g/(m2h). For 3# PyBE products, when the mass ratio of 3# pyridine base, butadiene monoxide and epoxyethane was 1:1.5:2, the inhibition effect of the synthesized product (3#PyBE 125) was better, when the dosage in corrosive media(60?) was 0.1%, the corrosion rate of N80 steel was 2.35 g/(m2h). When the dosage in corrosive media(90?) was 1.0%, the corrosion rate of N80 steel was 3.89 g/(m2h). All met the requirements of the first level of the related evaluation criteria. Showed that it had good corrosion inhibition effect in the medium acidification.In the meantime, evaluated inhibition properties of the 3# PyPE136 and 3# PyBE 125 for oilfield sewage of Tuo Liu station in Sheng Li oilfield. When the dosage the corrosive media was 30mg/L, the inhibition effect of the 3# PyPE136 was poor, probably due to the influence of other corrosive factors in the sewage.While 3# PyBE 125 was added to 55?corrosive media, the corrosion rate of A3 steel was 0.0108mm/a, the corrosion inhibition efficiency was 84.83%. Indicated 3# PyBE125 had good corrosion inhibition for sewage of this station.