Sulfourea-like carbon steel pickling corrosion inhibitor and application thereof

Abstract

The invention relates to a corrosion inhibitor production technical field, in particular to a thiourea-based carbon steel restrainer for avoiding unnecessary corrosion and acid liquor waste in the acid washing process of the carbon steel and manufactures and an application thereof. The corrosion inhibitor which is a compound or combination of the thiourea-based compounds uses the cleaning liquid added with the corrosion inhibitor to submerge and clean the carbon steel, wherein the cleaning liquid is the acid washing liquor of which the concentration is 0.1mol / L to 1mol / L, each liter of acid liquor is added with 0.001g to 2.0g of the corrosion inhibitor and submerges the carbon steel for 0.5 to 4 hours at room temperature. The components of the corrosion inhibitor of the invention are the thiourea-based compounds which have the advantages of non-toxicity, harmlessness, easy synthesis and easily bought and low priced raw materials; moreover, when the surfaces of the carbon steel and manufactures thereof are cleaned by the corrosion inhibitor of the invention, the excessive etching of the base metal and the excessive consumption of the acid liquor during the acid washing process are avoided, thereby the invention has the advantages of low use level, high efficiency and strong sustained action capability.

Description

technical field

[0001] The invention relates to the technical field of corrosion inhibitor production, in particular to a thiourea-based carbon steel pickling corrosion inhibitor used to prevent carbon steel and its products from unnecessary corrosion and acid consumption in the pickling process application. Background technique

[0002] Pickling is widely used in scale cleaning of heat exchange equipment, heat transfer equipment and cooling equipment in various industrial sectors. From the perspective of social economy, it can reduce the fuel consumption caused by dirt; from the perspective of environmental protection, it reduces fuel exhaust gas and air pollution; from the perspective of safety, thermal equipment such as boilers and heat exchangers are used Various types of dirt are gradually formed during the process, and the poor heat conduction of these dirt causes the local temperature of the furnace tube to rise, reduces the strength of the steel, and often causes tu...

Examples

Embodiment 1

[0018] The pickling solution is dilute hydrochloric acid, the concentration is 0.5M, the amount of pickling solution is 100L, and 1-N-(1'-(1',2',4'-triazole))acetyl-4-N-( 3”, 5”-dimethyl) benzoyl thiosemicarbazide 200g, just immerse the steel to be cleaned in the pickling solution for 2 hours at room temperature.

[0019] The highest corrosion inhibition efficiency obtained through experimental testing is 99%, which shows that it is an efficient cleaning agent.

Embodiment 2

[0021] The pickling solution is dilute hydrochloric acid, the concentration is 0.5M, the amount of pickling solution is 100L, and 1-N-(1'-(1',2',4'-triazole))acetyl-4-N-( 3”, 5”-dimethyl)benzoylthiosemicarbazide 15g and 1-N-(1’-(1’,2’,4’-triazole))acetyl-4-N-benzyl For 15g of acylthiosemicarbazide, immerse the steel to be cleaned in the pickling solution for 2 hours at room temperature.

[0022] The highest corrosion inhibition efficiency obtained through experimental testing is 97%, which shows that it is an efficient cleaning agent.

Embodiment 3

[0024] The pickling solution is dilute hydrochloric acid, the concentration is 1M, the amount of pickling solution is 100L, and 1-N-(1'-(1',2',4'-triazole))acetyl-4-N-benzyl For 50g of acylthiosemicarbazide, immerse the steel to be cleaned in the pickling solution for 0.5h at room temperature.

[0025] The highest corrosion inhibition efficiency obtained through experimental testing is 97%, which shows that it is an efficient cleaning agent.

technical field

[0001] The invention relates to the technical field of corrosion inhibitor production, in particular to a thiourea-based carbon steel pickling corrosion inhibitor used to prevent carbon steel and its products from unnecessary corrosion and acid consumption in the pickling process application. Background technique

[0002] Pickling is widely used in scale cleaning of heat exchange equipment, heat transfer equipment and cooling equipment in various industrial sectors. From the perspective of social economy, it can reduce the fuel consumption caused by dirt; from the perspective of environmental protection, it reduces fuel exhaust gas and air pollution; from the perspective of safety, thermal equipment such as boilers and heat exchangers are used Various types of dirt are gradually formed during the process, and the poor heat conduction of these dirt causes the local temperature of the furnace tube to rise, reduces the strength of the steel, and often causes tu...

Examples

Embodiment 1

[0018] The pickling solution is dilute hydrochloric acid, the concentration is 0.5M, the amount of pickling solution is 100L, and 1-N-(1'-(1',2',4'-triazole))acetyl-4-N-( 3”, 5”-dimethyl) benzoyl thiosemicarbazide 200g, just immerse the steel to be cleaned in the pickling solution for 2 hours at room temperature.

[0019] The highest corrosion inhibition efficiency obtained through experimental testing is 99%, which shows that it is an efficient cleaning agent.

Embodiment 2

[0021] The pickling solution is dilute hydrochloric acid, the concentration is 0.5M, the amount of pickling solution is 100L, and 1-N-(1'-(1',2',4'-triazole))acetyl-4-N-( 3”, 5”-dimethyl)benzoylthiosemicarbazide 15g and 1-N-(1’-(1’,2’,4’-triazole))acetyl-4-N-benzyl For 15g of acylthiosemicarbazide, immerse the steel to be cleaned in the pickling solution for 2 hours at room temperature.

[0022] The highest corrosion inhibition efficiency obtained through experimental testing is 97%, which shows that it is an efficient cleaning agent.

Embodiment 3

[0024] The pickling solution is dilute hydrochloric acid, the concentration is 1M, the amount of pickling solution is 100L, and 1-N-(1'-(1',2',4'-triazole))acetyl-4-N-benzyl For 50g of acylthiosemicarbazide, immerse the steel to be cleaned in the pickling solution for 0.5h at room temperature.

[0025] The highest corrosion inhibition efficiency obtained through experimental testing is 97%, which shows that it is an efficient cleaning agent.