Evaluation method for corrosion inhibitor used in alcohol ether alternative fuel system

Abstract

The invention relates to an evaluation method for a corrosion inhibitor used in an alcohol ether alternative fuel system. The method comprises the following steps: (1) placing a metal sample into a formic acid water solution which does not contain a corrosion inhibitor to be tested and a formic acid water solution which contains the corrosion inhibitor to be tested separately, using the metal sample as a working electrode to form a three-electrode electrochemical testing system, and performing steady state cathode and anode polarization curve testing through semi-logarithmic coordinates after a natural corrosion potential shown in the description is stabilized; (2) extrapolating a Tafel linear region of a cathode polarization curve to be intersected with a horizontal line of the stabilized natural corrosion potential shown in the description, and obtaining a natural corrosion current icorr. from the intersection point; (3) calculating a corrosion inhibition efficiency of the metal sample placed in the formic acid water solution which contains the corrosion inhibitor to be tested through the natural corrosion current icorr., so as to obtain the corrosion inhibition effect of the corrosion inhibitor to be tested. Compared with the prior art, the evaluation method has the advantages of being stable in data, fast, small in error and the like, and can realize rapid evaluation and screening of the corrosion inhibitor used in the alcohol ether alternative fuel system.

Description

technical field [0001] The invention relates to the field of alcohol ether alternative fuels, in particular to an evaluation method for alcohol ether alternative fuel system corrosion inhibitors. Background technique [0002] China's energy issues have become a major bottleneck restricting the sustainable development of the national economy, and directly affect the national energy strategy security. According to the data released by the General Administration of Customs on January 11, 2012, my country's dependence on imported crude oil reached 56.5% in 2011. Since becoming a net oil importer in 1993, my country's dependence on foreign crude oil has continued to increase, and will continue to increase for a long time to come. The National Development and Reform Commission has identified ten key energy-saving projects in the mid- and long-term special plans for energy conservation, one of which is to save and replace petroleum projects, develop alcohol-ether fuels, and promot...

AI Technical Summary

Problems solved by technology

[0004] However, there are two main problems in the use of alcohol ether alternative fuels: first, the water content in fuel alcohol will cause phase separation problems; chemical corrosion problem

The disadvantage is that the working electrode spacing of 1.0mm can easily cause the problem of stable diffusion of the solution, that is, the dissolved metal ions at the solution / interface cannot diffuse to the main solution in time, and the "depolarizer" in the main solution cannot pass through the two electrodes. Timely replenishment of the slits between them will inevitably affect the accuracy of the test; in addition, there is no quantitative comparison between the results of the EIS test and the results of the continuous immersion weight loss test

Images