High-temperature corrosion inhibitor and preparation method and application thereof

Abstract

The invention discloses a high-temperature corrosion inhibitor and a preparation method and application thereof. The corrosion inhibitor contains a compound A and a compound B; and the compound A is acompound has a structure shown as a formula (1) (please see the specifications for the formula), and the compound B is a compound with a structure shown as a formula (2) (please see the specifications for the formula), wherein R1 and R3 in the formula are the same or different and are selected from H and C<1-20> alkyl groups in a mutually-independent mode, R4 and R6 in the formula are the same ordifferent and are selected from H, C<1-20> alkyls and C<2-20> alkenyl groups in a mutually-independent mode, R2 and R5 in the formula are the same or different and are selected from C<1-20> alkylidene groups in a mutually-independent mode, and n is an integer greater than or equal to 1. Through compounding the compound A and the compound B in a specific range, the corrosion inhibitor capable of effectively inhibiting naphthenic acid in crude oil from corroding the metal surface in a high-temperature environment can be obtained; and the corrosion inhibition effect of the corrosion inhibitor isremarkably improved compared with that of the compound A or the compound B which is independently used, and the corrosion inhibition rate is stabilized to be 95% or above.

Description

technical field [0001] The invention belongs to the technical field of chemical anticorrosion, and in particular relates to a high-temperature corrosion inhibitor and its preparation method and application. Background technique [0002] High-acid crude oil has the characteristics of high acid value, high density, and high viscosity. Among them, the asphalt or colloid content is relatively high, which belongs to heavy oil or low-quality crude oil. Among them, the acid is mainly naphthenic acid, accounting for more than 95% of the total amount in crude oil. Naphthenic acid is mainly concentrated in the fraction at 250-500°C, and is distributed in the side streams of normal pressure and reduced pressure with the distillate oil. Generally, when the acid value of crude oil exceeds 0.5 mgKOH / g, naphthenic acid corrosion will occur in the temperature range of 220-425 ° C, and the parts with low fluid flow rate are uniform corrosion, while the parts with high fluid flow rate, such a...

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Problems solved by technology

In the prior art, the corrosion inhibition effect of a single high-temperature corrosion inhibitor is often not good, such as the problems of long film forming time and low corrosion inhibition rate.

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