Study On The Chlorine Corrosion Inhibition Of Tween 40 And Its Composite Corrosion Inhibitor In High Acid Solution

In the petroleum and chemical industry, the production and transport equipments are sometimes damaged or invalid because of corrosion. Chlorine ion content is high in the perchloric acid oil, which is very easy to cause the local corrosion of metal equipment. It sometimes leads the huge economic loss and safety accidents. There are many different measures to protect the metal, such as replacing the equipment of corrosion resistant materials and adding corrosion inhibitor. With low cost, non-toxic environmentally friendly corrosion inhibitors can not only greatly reduce the corrosion rate of the metal, but also can save cost. Adding corrosion inhibitor is effective and feasible, which has huge commercial value. Tween 40 is a surfactant, because it is low-cost, non-toxic environmental protection, and compound with good performance, we use it as a corrosion inhibitor. Tween 40 has huge potential in the field of anti-corrosion.In this paper, we use the weight loss method, corrosion rate curve measurement, polarization curve measurement and impedance curve measurement to investigate the corrosion inhibition of Tween 40 on the 316 L, N80, 20# steel in different concentrations, temperature and pH value. Tween 40 respectively with CTAB, sodium gluconate and zinc sulfate as binary combinations, investigate the optimal combination; use orthogonal experimental design to investigate the inhibition of ternary composite inhibitor of Tween 40, sodium gluconate and zinc sulfate for 316 L, N80, 20# steel.The experimental results show that corrosion solution temperature, pH value and concentration of corrosion inhibitor has a great influence on the corrosion inhibition performance of Tween 40; For different steel, Tween 40 has different optimal concentration; Tween 40 with different types of corrosion inhibitor combinations has a good inhibition effect,For 316 L, N80, 20# steel, the optimal combination of the binary composite inhibitor is all Tween 40 and zinc sulfate; The most influential factor of ternary composite inhibitor is different for different steels; By adding corrosion inhibitor, anticorrosion performance of N80 is very close to 316L; Under certain technological conditions, 20# steel can replace N80, and it has better anticorrosion performance than N80 by adding corrosion inhibitor sometimes.