阅读说明：本技术 一种金属离子螯合剂及其制备方法 (Metal ion chelating agent and preparation method thereof ) 是由 李俊华 张颖 李俊莉 程雯 任海晶 李霁阳 李移乐 王晓晖 于 2019-03-07 设计创作，主要内容包括：本发明提供一种金属离子螯合剂及其制备方法,涉及化工产品的领域,所述金属离子螯合剂无磷、腐蚀性低、除铁能力强,并能脱除多种金属离子。所述螯合剂包括以下重量份的原料：衣康酸10～25份,烯丙基聚氧乙烯醚4～10份,2-丙烯酰胺-2-甲基丙磺酸5～15份,30％氢氧化钠水溶液0.5～1.2份,40％过硫酸钠水溶液0.5～1.5份,20％亚硫酸氢钠水溶液0.3～0.8份,20％硫酸亚铁水溶液0.2～0.7份,聚天冬氨酸5～10份,聚环氧琥珀酸0～7份,亚氨基二琥珀酸四5～10份,水38～45份。其有益效果是：本发明的金属离子螯合剂为中性,对加药设备及管线的腐蚀性低,且分子中无磷元素,是一种环境友好型的螯合剂,可在催化裂解装置的电脱盐装置中使用。(The invention provides a metal ion chelating agent and a preparation method thereof, and relates to the field of chemical products. The chelating agent comprises the following raw materials in parts by weight: 10-25 parts of itaconic acid, 4-10 parts of allyl polyoxyethylene ether, 5-15 parts of 2-acrylamide-2-methylpropanesulfonic acid, 0.5-1.2 parts of 30% sodium hydroxide aqueous solution, 0.5-1.5 parts of 40% sodium persulfate aqueous solution, 0.3-0.8 part of 20% sodium bisulfite aqueous solution, 0.2-0.7 part of 20% ferrous sulfate aqueous solution, 5-10 parts of polyaspartic acid, 0-7 parts of polyepoxysuccinic acid, four 5-10 parts of iminodisuccinic acid and 38-45 parts of water. The beneficial effects are as follows: the metal ion chelating agent is neutral, has low corrosivity on dosing equipment and pipelines, contains no phosphorus element in molecules, is an environment-friendly chelating agent, and can be used in an electric desalting device of a catalytic cracking device.)

1. A metal ion chelating agent characterized by: the chelating agent comprises the following raw materials in parts by weight:

2. a preparation method of a metal ion chelating agent is characterized by comprising the following steps:

(1) dissolving 10-25 parts of itaconic acid, 4-10 parts of allyl polyoxyethylene ether, 5-15 parts of 2-acrylamide-2-methylpropanesulfonic acid and 38-45 parts of water uniformly at 50 ℃, adjusting the pH to 6.5-7.0 by using 0.5-1.2 parts of sodium hydroxide solution, and introducing nitrogen for 15min in a sealed manner;

(2) sequentially adding 0.3-0.8 part of sodium bisulfite aqueous solution and 0.2-0.7 part of ferrous sulfate aqueous solution into the mixed solution treated in the step (1), uniformly stirring, and heating to 75 +/-2 ℃;

(3) dropwise adding 0.5-1.5 parts of sodium persulfate aqueous solution into the mixed solution treated in the step (2), wherein the dropwise adding time lasts for 1-1.5 hours, and then heating to 85 +/-2 ℃;

(4) reacting the mixed solution treated in the step (3) for 3 hours to obtain colorless viscous liquid;

(5) and (4) cooling the colorless viscous liquid obtained in the step (4) to room temperature, adding 5-10 parts of polyaspartic acid, 0-7 parts of polyepoxysuccinic acid and 5-10 parts of imino tetrasodium disuccinate, and uniformly stirring to obtain the metal ion chelating agent.

3. The method according to claim 2, wherein in the step (1), the aqueous sodium hydroxide solution is a 30% aqueous sodium hydroxide solution.

4. The method according to claim 2, wherein in the step (2), the aqueous solution of sodium bisulfite is a 20% aqueous solution of sodium bisulfite, and the aqueous solution of ferrous sulfate is a 20% aqueous solution of ferrous sulfate.

5. The method according to claim 2, wherein in the step (3), the aqueous solution of sodium persulfate is a 40% aqueous solution of sodium persulfate.

Technical Field

The invention relates to the field of chemical products, in particular to a metal ion chelating agent and a preparation method thereof, and particularly relates to a chelating agent added into an electric desalting device of a crude oil and residual oil catalytic cracking device.

Background

Along with the exploitation of oil and gas resources in China, oil well pipelines and equipment are increasingly corroded, a large amount of iron elements in metal pipelines and equipment enter oil and enter a refining system along with crude oil to be accumulated in the oil, and the metal elements including the iron elements can cause the energy efficiency of a catalytic cracking device to be reduced, so that the activity of a catalyst is influenced, and even a catalyst poisoning event is caused.

Iron has become one of the most important metal elements affecting the life of the catalyst. The existing methods for removing metal elements mainly comprise a chelation method, a hydrogenation catalysis method, biological demetalization, filtration demetalization, membrane separation demetalization and CO₂Demetallization and the like. Among them, the simplest and feasible is the chelation method, which is low in investment, takes effect quickly, and can be used in combination with an electric desalting process.

The chelating agent components disclosed in the prior patents and documents mainly include acetic acid, citric acid, oxalic acid, phosphoric acid, metaphosphoric acid, EDTA, hydroxycarboxylic acids, aminocarboxylic acids, and the like. Most of the chelating agents are acidic, the pH value is 1-2, and the chelating agents have strong corrosivity on dosing equipment and pipelines, and particularly the corrosion on welding seams and elbow parts is very obvious. In addition, the low molecular acidic compounds contained in the oil can enter the tops of the atmospheric tower and the vacuum tower along with the oil products after the temperature rises, thereby causing the corrosion of the tops of the towers. In addition, most chelating agents contain phosphorus, so that secondary pollution of water is easily caused.

Therefore, the development of a chelating agent which is phosphorus-free, low in corrosivity and strong in metal removal capability is of great significance.

Disclosure of Invention

The chelating agent disclosed by the invention is free of phosphorus, low in corrosivity and strong in iron removal capacity, and can remove various metal ions.

The invention provides a metal ion chelating agent, which has the technical scheme that:

a metal ion chelating agent characterized by: the chelating agent comprises the following raw materials in parts by weight:

the invention also discloses a preparation method of the metal ion chelating agent, which is characterized by comprising the following steps:

(1) dissolving 10-25 parts of itaconic acid, 4-10 parts of allyl polyoxyethylene ether, 5-15 parts of 2-acrylamide-2-methylpropanesulfonic acid and 38-45 parts of water uniformly at 50 ℃, adjusting the pH to 6.5-7.0 by using 0.5-1.2 parts of sodium hydroxide solution, and introducing nitrogen for 15min in a sealed manner;

(2) sequentially adding 0.3-0.8 part of sodium bisulfite aqueous solution and 0.2-0.7 part of ferrous sulfate aqueous solution into the mixed solution treated in the step (1), uniformly stirring, and heating to 75 +/-2 ℃;

(3) dropwise adding 0.5-1.5 parts of sodium persulfate aqueous solution into the mixed solution treated in the step (2), wherein the dropwise adding time lasts for 1-1.5 hours, and then heating to 85 +/-2 ℃;

(4) reacting the mixed solution treated in the step (3) for 3 hours to obtain colorless viscous liquid;

(5) and (4) cooling the colorless viscous liquid obtained in the step (4) to room temperature, adding 5-10 parts of polyaspartic acid, 0-7 parts of polyepoxysuccinic acid and 5-10 parts of imino tetrasodium disuccinate, and uniformly stirring to obtain the metal ion chelating agent.

Wherein, in the step (1), the sodium hydroxide aqueous solution is a 30% sodium hydroxide aqueous solution.

Wherein, in the step (2), the sodium bisulfite aqueous solution is a 20% sodium bisulfite aqueous solution, and the ferrous sulfate aqueous solution is a 20% ferrous sulfate aqueous solution.

Wherein, in the step (3), the aqueous sodium persulfate solution is a 40% aqueous sodium persulfate solution.

The implementation of the invention comprises the following technical effects:

the co-monomers of the chelating agent are itaconic acid, allyl polyoxyethylene ether and 2-acrylamide-2-methylpropanesulfonic acid; the itaconic acid has a plurality of carboxyl groups, on one hand, the water solubility of the polymer can be improved, the contact area and the opportunity of the chelating agent and organic metal ions on an oil-water phase interface are enhanced, and on the other hand, the carboxylate radical has strong chelating capacity and can tightly chelate metal ions; the ether bond in the allyl polyoxyethylene ether has strong hydrophilicity, and oxygen atoms in the molecule of the allyl polyoxyethylene ether and hydrogen in water can form weak hydrogen bonds to introduce hydrophilic groups between molecules, so that the tolerance of metal ions is greatly improved; 2-acrylamide-2-methylpropanesulfonic acid can enhance the temperature resistance and salt resistance of the polymer, and the sulfonic acid group in the monomer has good water solubility; and the synergistic chelation effect of the polyaspartic acid, the polyepoxysuccinic acid and the tetrasodium iminodisuccinate is added, so that the chelating agent has stronger metal removing capacity. The chelating agent is neutral, has low corrosivity on dosing equipment and pipelines, has no phosphorus element in molecules, is an environment-friendly chelating agent, and can be used in an electric desalting device of a catalytic cracking device.

Detailed Description

Exemplary embodiments will now be described in detail, examples of which are illustrated herein. The following description refers to the same or similar elements in different figures unless otherwise indicated. The implementations described in the exemplary embodiments below are not intended to represent all implementations consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the present disclosure, as detailed in the appended claims.

The metal ion chelating agent comprises the following raw materials in parts by weight:

the co-monomers of the chelating agent are itaconic acid, allyl polyoxyethylene ether and 2-acrylamide-2-methylpropanesulfonic acid; the itaconic acid has a plurality of carboxyl groups, on one hand, the water solubility of the polymer can be improved, the contact area and the opportunity of the chelating agent and organic metal ions on an oil-water phase interface are enhanced, and on the other hand, the carboxylate radical has strong chelating capacity and can tightly chelate metal ions; the ether bond in the allyl polyoxyethylene ether has strong hydrophilicity, and oxygen atoms in the molecule of the allyl polyoxyethylene ether and hydrogen in water can form weak hydrogen bonds to introduce hydrophilic groups between molecules, so that the tolerance of metal ions is greatly improved; 2-acrylamide-2-methylpropanesulfonic acid can enhance the temperature resistance and salt resistance of the polymer, and the sulfonic acid group in the monomer has good water solubility; and the synergistic chelation effect of the polyaspartic acid, the polyepoxysuccinic acid and the tetrasodium iminodisuccinate is added, so that the chelating agent has stronger metal removing capacity. The chelating agent is neutral, has low corrosivity on dosing equipment and pipelines, has no phosphorus element in molecules, is an environment-friendly chelating agent, and can be used in an electric desalting device of a catalytic cracking device.

The invention also provides a preparation method of the metal ion chelating agent, which is characterized by comprising the following steps:

(1) dissolving 10-25 parts of itaconic acid, 4-10 parts of allyl polyoxyethylene ether, 5-15 parts of 2-acrylamide-2-methylpropanesulfonic acid and 38-45 parts of water uniformly at 50 ℃, adjusting the pH to 6.5-7.0 by using 0.5-1.2 parts of sodium hydroxide solution, and introducing nitrogen for 15min in a sealed manner;

(2) sequentially adding 0.3-0.8 part of sodium bisulfite aqueous solution and 0.2-0.7 part of ferrous sulfate aqueous solution into the mixed solution treated in the step (1), uniformly stirring, and heating to 75 +/-2 ℃;

(3) dropwise adding 0.5-1.5 parts of sodium persulfate aqueous solution into the mixed solution treated in the step (2), wherein the dropwise adding time lasts for 1-1.5 hours, and then heating to 85 +/-2 ℃;

(4) reacting the mixed solution treated in the step (3) for 3 hours to obtain colorless viscous liquid;

(5) and (4) cooling the colorless viscous liquid obtained in the step (4) to room temperature, adding 5-10 parts of polyaspartic acid, 0-7 parts of polyepoxysuccinic acid and 5-10 parts of imino tetrasodium disuccinate, and uniformly stirring to obtain the metal ion chelating agent.

Wherein, in the step (1), the sodium hydroxide aqueous solution is a 30% sodium hydroxide aqueous solution.

Wherein, in the step (2), the sodium bisulfite aqueous solution is a 20% sodium bisulfite aqueous solution, and the ferrous sulfate aqueous solution is a 20% ferrous sulfate aqueous solution.

Wherein, in the step (3), the aqueous sodium persulfate solution is a 40% aqueous sodium persulfate solution.

The following will describe a method for preparing the metal ion chelating agent provided by the present invention with specific examples.