CN-121669323-B - Composite metal passivator and preparation method thereof

CN121669323BCN 121669323 BCN121669323 BCN 121669323BCN-121669323-B

Abstract

The application belongs to the technical field of metal passivating agents, and particularly provides a composite metal passivating agent and a preparation method thereof, wherein the composite metal passivating agent comprises the following steps of taking magnesium carbonate and barium carbonate, mixing, adding nitric acid for dissolving, then adjusting pH to 5.5-6.3, heating, adding enzymolysis peptide, alkylated cyclodextrin and diisooctyl phosphate, and stirring to obtain the composite metal passivating agent; the enzymolysis peptide is obtained by purifying soybean meal after hydrolysis by composite protease, and the alkylated cyclodextrin is obtained by modifying cyclodextrin by a silane coupling agent. The composite metal passivating agent prepared by the method has good synergistic effect and can improve the use activity of the catalyst.

Inventors

GUO JINGYU
ZHANG HONGJIANG
QI QI
Qi Zhanyou
YANG CUIYING

Assignees

淄博昌聚源环保科技有限公司

Dates

Publication Date: 20260505
Application Date: 20260210

Claims (5)

1. The preparation method of the composite metal passivating agent is characterized by comprising the following steps of: mixing magnesium carbonate and barium carbonate, adding nitric acid for dissolution, then adjusting the pH value to 5.5-6.3, heating, adding enzymolysis peptide, alkylated cyclodextrin and diisooctyl phosphate, and stirring to obtain the product, wherein the mass ratio of the magnesium carbonate to the barium carbonate to the enzymolysis peptide to the alkylated cyclodextrin to the diisooctyl phosphate is (0.7-0.8) (0.2-0.5) (4-5) (2.2-2.7) (0.3-0.5); The preparation of the enzymatic hydrolysis peptide comprises the following steps: S01, sieving soybean meal, adjusting the solid-to-liquid ratio, adding water, performing ultrasonic treatment, and then heating and denaturing to obtain a suspension for later use, wherein the temperature of heating and denaturing is 90-93 ℃; s02, taking suspension, regulating pH, cooling, adding compound protease into the suspension according to the adding amount of 70-80mg per gram of soybean meal, performing enzymolysis treatment, inactivating enzyme, refrigerating overnight at 2 ℃, centrifuging, concentrating the supernatant, and freeze-drying to obtain the final product; The compound protease is prepared by compounding alkaline protease and papain according to the mass ratio of 1 (0.5-1); The preparation of the alkylated cyclodextrin comprises the following steps: And (3) dispersing beta-cyclodextrin in absolute ethyl alcohol, adding a silane coupling agent, heating, stirring for reaction, adding acetone for precipitation, and purifying to obtain the beta-cyclodextrin.
2. The method for preparing the composite metal passivating agent according to claim 1, wherein in the step S01, the solid-to-liquid ratio is 1 (15-20), and the ultrasonic power is set to be 100-200W.
3. The method for preparing a composite metal passivating agent according to claim 1, wherein the beta-cyclodextrin, The mass volume ratio of the absolute ethyl alcohol and the silane coupling agent is (3.2-3.7) g (30-40) mL (1.1-1.5) g.
4. The method for preparing a composite metal passivating agent according to claim 1, wherein the silane coupling agent has a structural formula: wherein r=me/Et, R ́ =c n H (2n+1) , n=12-18.
5. A composite metal passivator prepared by the preparation method of any one of claims 1-4.

Description

Composite metal passivator and preparation method thereof Technical Field The application belongs to the technical field of metal passivating agents, and particularly relates to a composite metal passivating agent and a preparation method thereof. Background In the catalytic cracking process, raw oil often contains heavy metal impurities such as nickel, vanadium and the like, which exist in the form of organic metal compounds and are difficult to thoroughly remove. Under the high temperature oxidation environment of the regenerator, these compounds decompose to metal oxides and deposit on the catalyst surface. Wherein, the deposition of nickel can significantly enhance the dehydrogenation activity of the catalyst, resulting in increased hydrogen and coke yields, while the deposition of vanadium can further migrate and convert to acidic species, destroying the zeolite crystal structure, blocking the catalyst pore channels, resulting in a permanent decrease in catalyst activity. In order to alleviate the adverse effects of the heavy metal pollution, a method of adding a metal passivating agent is generally adopted in industry. The passivating agent often contains active components such as antimony, magnesium, lanthanum, barium and the like, and the action mechanism is to form a stable low-activity compound or alloy phase through interaction between the components and heavy metals deposited on the surface of the catalyst, so that the harmful effects of the heavy metals are inhibited, and the structural and performance integrity of the catalyst is protected. According to the kinds of heavy metals, the passivating agent can be divided into a single-component special agent and a multi-component complexing agent. The multicomponent complexing agent can simultaneously relieve the pollution of various metals such as nickel, vanadium and the like in theory, and has better application prospect. However, in practical application, the synergistic effect between different components is not obvious, the proportion is difficult to optimize, and the like, so that the overall passivation effect cannot reach the expectations. Therefore, developing a novel composite metal passivating agent with obvious synergistic effect and capable of effectively inhibiting various heavy metal pollution and further perfecting the preparation process thereof has become an important research direction in the field. Disclosure of Invention Aiming at the problems, the application provides a composite metal passivator and a preparation method thereof in order to further improve the synergistic effect of all components of the passivator and improve the catalyst use activity. The application firstly provides a preparation method of a composite metal passivating agent, which comprises the following steps: Mixing magnesium carbonate and barium carbonate, adding nitric acid for dissolution, then adjusting the pH to 5.5-6.3, heating, adding enzymolysis peptide, alkylated cyclodextrin and diisooctyl phosphate, and stirring to obtain the final product; The enzymolysis peptide is obtained by purifying soybean meal after hydrolysis by composite protease; the alkylated cyclodextrin is obtained by modifying cyclodextrin by a silane coupling agent; the mass ratio of the magnesium carbonate to the barium carbonate to the enzymatic hydrolysis peptide to the alkylated cyclodextrin to the diisooctyl phosphate is (0.7-0.8), (0.2-0.5), (4-5), (2.2-2.7) and (0.3-0.5). Further, the preparation of the enzymatic hydrolysis peptide comprises the following steps: s01, sieving soybean meal, adjusting the solid-to-liquid ratio, adding water, performing ultrasonic treatment, and then heating and denaturing to obtain a suspension for later use; s02, taking suspension, regulating pH, cooling, adding compound protease, performing enzymolysis treatment, inactivating enzyme, refrigerating at 2 ℃ overnight, centrifuging, concentrating supernatant, and freeze-drying to obtain the final product; In the step S01, the solid-to-liquid ratio is 1 (15-20), and the ultrasonic power is set to be 100-200W; the temperature rise and denaturation temperature is 90-93 ℃. In step S02, the composite protease is prepared by compounding alkaline protease and papain according to the mass ratio of 1 (0.5-1), and the composite protease is added into the suspension according to the adding amount of 70-80mg per gram of soybean meal. Further, the preparation of the alkylated cyclodextrin comprises the following steps: Dispersing beta-cyclodextrin in absolute ethyl alcohol, adding a silane coupling agent, heating, stirring for reaction, adding acetone for precipitation, and purifying to obtain the beta-cyclodextrin; the mass volume ratio of the beta-cyclodextrin to the absolute ethyl alcohol to the silane coupling agent is (3.2-3.7) g (30-40) mL (1.1-1.5); The structural formula of the silane coupling agent is as follows: wherein r=me/Et, R ́ =c nH(2n+1), n=12-18. The application also provides a composite