CN115920846A - Sulfur group loaded demercuration adsorbent and preparation method thereof - Google Patents

Abstract

The invention relates to the technical field of adsorbents, and discloses a sulfur group loaded mercury removal adsorbent and a preparation method thereof, wherein the mercury removal adsorbent comprises a carbon carrier and a sulfur group element loaded on the carbon carrier; the carbon system carrier takes triethylalkynyl benzene and dibromocarbazole as raw materials, a precursor is obtained through coupling reaction, and the precursor is carbonized and activated and then loaded with sulfur group elements to obtain the demercuration adsorbent. The carbon system carrier is a carbon system carrier of the demercuration adsorbent, and compared with the existing activated carbon, the carbon system carrier has the advantages of large specific surface area, porosity, easily-regulated structure and good stability, and the adsorption quantity of the sulfur group element can be increased. In addition, the carbon-based carrier formed by the method has higher thermal stability, so that the demercuration performance can be further improved at a higher sulfur-carrying temperature.

Description

Sulfur group loaded demercuration adsorbent and preparation method thereof

Technical Field

The invention relates to the technical field of adsorbents, in particular to a sulfur group supported demercuration adsorbent and a preparation method thereof.

Background

With the current great promotion of energy conservation and emission reduction, the current demand for natural gas is rapidly increased.

Currently, natural gas collected by mining contains various combustible and non-combustible gases, and also includes impurities such as hydrogen sulfide, carbon dioxide, organic sulfur, mercury and the like. Mercury belongs to a common harmful element in natural gas, and the existence of mercury can bring certain potential safety hazard. Meanwhile, mercury is likely to cause corrosion of aluminum equipment during the production of natural gas.

In the current mercury removal adsorbent, activated carbon is the most commonly used adsorbent, and the purpose of removing mercury is achieved by utilizing the reaction of sulfur element loaded on activated carbon and mercury to form mercury sulfide. The sulfur-carrying activated carbon is related to the amount of sulfur carried and the temperature of the sulfur carried. The adsorption capacity and the temperature resistance of the existing activated carbon are both poor in price; in addition, the activated carbon has low strength and is easily damaged during the adsorption-regeneration pneumatic conveying process, so that the loss is large.

Disclosure of Invention

< problems to be solved by the present invention >

The method is used for solving the problem of poor adsorption effect of the activated carbon adsorbent for demercuration in the prior art.

< technical solution adopted in the present invention >

In view of the above problems, the present invention provides a chalcogen-supported demercuration adsorbent and a method for producing the same.

The specific contents are as follows:

the invention provides a sulfur group supported mercury removal adsorbent, which comprises a carbon carrier and a sulfur group element supported on the carbon carrier; the carbon system carrier takes triethylalkynyl benzene and dibromocarbazole as raw materials, a precursor is obtained through coupling reaction, and the precursor is carbonized and activated and then loaded with sulfur group elements to obtain the demercuration adsorbent.

Secondly, the invention provides a chalcogen supported demercuration adsorbent mentioned above, which comprises the following steps:

s1, adding a catalyst, a reaction solvent and triethylamine into triethylalkynyl benzene and dibromocarbazole in an inert atmosphere, and reacting, washing and filtering to obtain a precursor;

s2, completely carbonizing the precursor in an inert atmosphere, and naturally cooling to obtain a carbonized body;

and S3, in the presence of a solvent, impregnating the carbonized body and the slurry containing the chalcogen element, and drying to obtain the mercury removal adsorbent.

< technical mechanism and advantageous effects of the present invention >

The carbon system carrier is a carbon system carrier of the demercuration adsorbent, and compared with the existing activated carbon, the carbon system carrier has the advantages of large specific surface area, porosity, easily-regulated structure and good stability, and the adsorption quantity of the sulfur group element can be increased. In addition, the carbon-based carrier formed by the method has higher thermal stability, and the demercuration performance can be further improved at a higher sulfur-carrying temperature.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

< technical means >

The invention provides a sulfur group supported demercuration adsorbent, which comprises a carbon-based carrier and a sulfur group element supported on the carbon-based carrier; the carbon system carrier takes triethylalkynyl benzene and dibromocarbazole as raw materials, a precursor is obtained through coupling reaction, and the precursor is carbonized and activated and then loaded with sulfur group elements to obtain the demercuration adsorbent.

In the present invention, the chalcogen element includes at least one of sulfur, selenium, and tellurium.

In the invention, the sulfur family element accounts for 0.05-0.2 of the mass of the carbon series carrier.

In the invention, the intermediate loaded with the chalcogen element is grafted with the silver coating layer. Specifically, the grafting is obtained by the mechanochemical reaction of an intermediate and a silver coating in the presence of a silane coupling agent. Specifically, grinding for 40-50 times under the action of a mechanochemical,

in the invention, the silver coating layer is a molecular sieve adsorbed with silver, and the mass ratio of the intermediate to the silver to the molecular sieve is 1.

The preparation method of the molecular sieve adsorbing silver comprises the steps of dropwise adding a silver nitrate solution into the molecular sieve, carrying out equal-volume impregnation, drying and roasting to obtain the silver-adsorbed molecular sieve.

More specifically, the roasting process parameter is 400-600 ℃ and 0.5-2 h.

Secondly, the invention provides a chalcogen supported demercuration adsorbent mentioned above, which comprises the following steps:

s1, adding a catalyst, a reaction solvent and triethylamine into triethylalkynyl benzene and dibromocarbazole in an inert atmosphere, and reacting, washing and filtering to obtain a precursor;

s2, completely carbonizing the precursor in an inert atmosphere, and naturally cooling to obtain a carbonized body;

and S3, in the presence of a solvent, impregnating the carbonized body and the slurry containing the chalcogen element, and drying to obtain the mercury removal adsorbent.

In the invention, in S1, the molar ratio of the triacetynyl carbon to the dibromocarbazole to the catalyst is 1.

In the invention, in S2, the carbonization temperature is 600-1000 ℃.

< example >

Example 1

The preparation method of the demercuration adsorbent comprises the following steps:

(1) Adding 1mmol of 1,3, 5-triethylynylbenzene and 0.5mmol of 3, 6-dibromocarbazole into a reaction mixture in an argon atmosphere, adding 0.1mmol of palladium acetate/cuprous iodide (1.

(2) The precursor is completely carbonized at 800 ℃ in the argon atmosphere, and then naturally cooled to obtain a carbonized body.

(3) After the sulfur powder is treated by conventional acid, the sulfur powder and a carbide (the mass ratio is 1.

(4) Dropwise adding silver nitrate solution (with pH value adjusted to be alkalescent) into zeolite molecular sieve, soaking in the same volume, drying (100 ℃,1 h), and roasting to obtain the product; the roasting process parameters are 500 ℃ and 1h; the impregnation is carried out at 50 ℃; finally obtaining the coating layer absorbed with silver.

(3) Adding the coating layer adsorbed with silver, the intermediate and the silane coupling agent into a mechanochemical reactor, and grinding for 40-50 times to obtain the mercury removal adsorbent. The mass ratio of the coating layer adsorbed with silver, the intermediate and the silane coupling agent is 0.3.

Example 2

This example differs from example 1 in that the molar ratio of 1,3, 5-triethylynylbenzene, 3, 6-dibromocarbazole, palladium acetate/cuprous iodide (1.

Example 3

This example is different from example 1 in that (3) and (4) are not present.

< comparative example >

Comparative example 1

This comparative example differs from example 1 in that activated carbon impregnated sulfur powder was selected.

< test example >

The demercuration adsorbents obtained in examples 1 to 3 and comparative example 1 were used as samples to perform tests.

The mercury removing agent of the sample is subjected to mercury removing performance test (normal temperature and normal pressure).

The test conditions were: the loading of the mercury removing agent is 20mL, the mercury content is controlled to be 1-1.5ug/g, the adsorption reaction is stopped when the outlet mercury content is more than 10ng/g, and the experimental results are shown in Table 1.

TABLE 1 desulfurization Performance of desulfurizing agent

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (10)

1. The sulfur group supported demercuration adsorbent is characterized by comprising a carbon-based carrier and a sulfur group element supported on the carbon-based carrier; the carbon system carrier takes triethylalkynyl benzene and dibromocarbazole as raw materials, a precursor is obtained through coupling reaction, and the precursor is carbonized and activated and then loaded with sulfur group elements to obtain the demercuration adsorbent.

2. The chalcogen-supported demercuration adsorbent as claimed in claim 1, wherein the chalcogen comprises at least one of sulfur, selenium and tellurium.

3. The chalcogen-supported demercuration adsorbent according to claim 1 or 2, wherein the chalcogen element accounts for 0.05 to 0.2 of the mass of the carbon-based carrier.

4. The chalcogen-supported demercuration adsorbent according to any one of claims 1 to 3, wherein the chalcogen-supported intermediate is grafted with a silver-based coating layer.

5. The chalcogen-supported demercuration adsorbent according to claim 4, wherein the silver-based coating layer is a molecular sieve adsorbing silver, and the mass ratio of the intermediate to the silver to the molecular sieve is 1: 0.01-0.1.

6. The chalcogen-supported demercuration adsorbent according to claim 5, wherein the molecular sieve adsorbed with silver is prepared by dropping a silver nitrate solution into the molecular sieve, impregnating, drying, and calcining.

7. The chalcogen-supported mercury-removing adsorbent according to claim 6, wherein the calcination process parameters are 400-600 ℃ for 0.5-2 h.

8. The chalcogen-supported demercuration adsorbent according to any one of claims 1 to 7, comprising the steps of:

s1, adding a catalyst, a reaction solvent and triethylamine into triethylalkynyl benzene and dibromocarbazole in an inert atmosphere, and reacting, washing and filtering to obtain a precursor;

s2, completely carbonizing the precursor in an inert atmosphere, and naturally cooling to obtain a carbonized body;

and S3, in the presence of a solvent, impregnating the carbonized body and the slurry containing the chalcogen element, and drying to obtain the mercury removal adsorbent.

9. The chalcogen-supported demercuration adsorbent according to claim 8, wherein in S1,

the molar ratio of the triacetylcarbon to the dibromocarbazole to the catalyst is 1.3-0.6.

10. The chalcogen-supported demercuration adsorbent according to claim 9 or 10, wherein the carbonization temperature in S2 is 600 to 1000 ℃.