High-temperature dechlorinating agent and preparation method thereof

Abstract

The invention belongs to the technical field of reforming pre-hydrogenation high-temperature dechlorination, and discloses a high-temperature dechlorination agent and a preparation method thereof.The high-temperature dechlorination agent is prepared from, by weight, 55-75 parts of calcium hydroxide, 10-25 parts of gamma-crystal-form aluminum oxide slag, 5-35 parts of pseudo-boehmite and 2-9 parts of auxiliaries. The dechlorinating agent is prepared by mixing and kneading calcium hydroxide and alumina slag, grinding, extruding into strips, drying at 120 DEG C for 2 hours, and roasting at 450-550 DEG C for 4 hours. According to the invention, the low-value or no-value catalyst alumina solid slag is mixed with calcium hydroxide, and a proper amount of auxiliary agent is added, so that the forming performance is improved, and the high-temperature dechlorinating agent is prepared. The side pressure strength of the dechlorinating agent reaches 100 N / cm or above, the highest strength reaches 220 N / cm or above, the penetrating chlorine capacity is 35% wt or above, and the highest penetrating chlorine capacity reaches 56% wt.

Description

Technical Field

[0001] The present invention belongs to the technical field of high-temperature dechlorination in reforming pre-hydrogenation, and relates to a high-temperature dechlorination agent and a preparation method thereof. Background Art

[0002] With the increase in the depth of crude oil exploitation and the intensification of the reforming process, chlorinated hydrocarbon additives are widely used in multiple links to improve the recovery rate. These chlorides ultimately enter the crude oil. After being distilled by the atmospheric and vacuum distillation units of the refinery, most of the organic chlorides in the crude oil are concentrated in the reforming feedstock oil at the top of the primary and atmospheric columns. During the raw material pretreatment process of the reforming unit, organic chlorides are hydrogenated to form hydrogen chloride, generating a strongly corrosive medium. A large number of various dechlorination agents are being used in the reforming unit to ensure the long-term, safe, and efficient operation of the unit. Dechlorination agents generally use metal oxides such as sodium, calcium, and copper as the main active components. After being formed at a high proportion, the strength of metal oxides is generally not high, and at the same time, the pore volume is small, which is not conducive to the diffusion of the raw material in the dechlorination agent. Dechlorination agents using alumina as the carrier generally have many advantages such as large pore volume and high strength, but the raw material price is high, and the market competitiveness is poor. Summary of the Invention

[0003] In order to solve the technical problems existing in the prior art, the present invention uses the high-purity alumina slag generated during the preparation of the catalyst, in combination with calcium element oxides, to prepare a high-temperature dechlorination agent. While having the advantages of alumina dechlorination agents, the raw material cost is reduced, and the market competitiveness is improved. At the same time, through this technology, the secondary utilization of the catalyst slag is completed, meeting the technical requirements of green environmental protection.

[0004] The above object of the present invention is achieved by the following technical solutions:

[0005] A high-temperature dechlorination agent includes calcium hydroxide, alumina slag, pseudo-boehmite, and additives.

[0006] Further, the additives include one or more of hydroxypropyl methylcellulose, polyvinyl alcohol, and nitric acid.

[0007] Further, the alumina slag is γ-crystalline alumina slag.

[0008] Further, calcium oxide is 55 - 75 parts by weight, γ-crystalline alumina slag is 10 - 25 parts by weight, pseudo-boehmite is 5 - 35 parts by weight, and additives are 2 - 9 parts by weight.

[0009] A preparation method of a high-temperature dechlorination agent is to mix, roll, extrude, dry, and calcine calcium hydroxide and alumina slag by combining pseudo-boehmite and additives to prepare the dechlorination agent.

[0010] Further, the drying temperature is 120°C.

[0011] Further, the drying time is 2 hours.

[0012] Further, the calcination temperature is 450 - 550 °C.

[0013] Further, the calcination time is 4 hours.

[0014] The beneficial effects of the present invention compared with the prior art are as follows:

[0015] By mixing low - value or valueless catalyst alumina solid slag with calcium hydroxide, adding appropriate additives to improve its molding performance, a high - temperature dechlorination agent is prepared. The side pressure strength of the dechlorination agent reaches above 100 N / cm, the highest strength reaches above 220 N / cm, the breakthrough chlorine capacity is above 35% wt, and the highest breakthrough chlorine capacity reaches 56% wt. Specific Embodiments

[0016] The following will specifically describe the content of the present invention in conjunction with specific embodiments. The examples described below are only the preferred embodiments of the present invention. It should be noted that the following description is only for explaining the present invention and does not impose any form of limitation on the present invention. Any simple modification, equivalent change and modification made to the embodiments according to the technical essence of the present invention all fall within the scope of the technical solution of the present invention. In the following embodiments, the materials, reagents, etc. used are obtained from commercial channels without special instructions.

[0017] The present invention uses calcium hydroxide as the main component, in combination with porous materials such as γ - crystalline alumina slag and pseudo - boehmite, and adds a certain proportion of additives. The additives include one or several of hydroxypropyl methylcellulose, polyvinyl alcohol, and nitric acid. Among them, calcium oxide is 55 - 75 parts by weight, γ - crystalline alumina slag is 10 - 25 parts by weight, pseudo - boehmite is 5 - 35 parts by weight, and the additive is 2 - 9 parts by weight. The viscosity of the calcined γ - crystalline alumina slag is poor. By combining pseudo - boehmite and auxiliary additives, calcium hydroxide and alumina slag are kneaded, rolled, and extruded into strips, dried at 120 °C for 2 hours, and calcined at 450 - 550 °C for 4 hours to obtain the dechlorination agent.

[0018] Comparative Example 1

[0019] Weigh 27.8 g of γ-alumina slag material crushed into 200-mesh powder, weigh 14.9 g of pseudo-boehmite, mix the two powders, add 2 g of hydroxypropyl methylcellulose and 3.5 g of polyvinyl alcohol. After mixing evenly, add 3.4 g of 65% nitric acid to 100 g of water, then add the mixed powder for kneading. After mixing evenly, add 85.9 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, perform extrusion molding. Extrude into a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 500 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 150 N / cm, and the breakthrough chlorine capacity is 50%.

[0020] Example 1

[0021] Weigh 11.1 g of γ-alumina slag material crushed into 200-mesh powder, weigh 52.2 g of pseudo-boehmite, mix the two powders, add 2.5 g of hydroxypropyl methylcellulose and 3.5 g of polyvinyl alcohol. After mixing evenly, add 4.6 g of 65% nitric acid to 100 g of water, then add the mixed powder for kneading. After mixing evenly, add 72.7 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, perform extrusion molding. Extrude into a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 450 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 213.2 N / cm, and the breakthrough chlorine capacity is 37%.

[0022] Example 2

[0023] Weigh 11.1 g of γ-alumina slag material crushed into 200-mesh powder, weigh 52.2 g of pseudo-boehmite, mix the two powders, add 2.5 g of hydroxypropyl methylcellulose and 3.5 g of polyvinyl alcohol. After mixing evenly, add 4.6 g of 65% nitric acid to 100 g of water, then add the mixed powder for kneading. After mixing evenly, add 72.7 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, perform extrusion molding. Extrude into a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 550 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 221.5 N / cm, and the breakthrough chlorine capacity is 39%.

[0024] Example 3

[0025] Weigh 11.1 g of γ-alumina slag material crushed into 200-mesh powder, and weigh 52.2 g of pseudo-boehmite. Mix the two powders, add 0.5 g of hydroxypropyl methylcellulose and 0.5 g of polyvinyl alcohol. After mixing evenly, add 1.5 g of 65% nitric acid to 100 g of water, then add the mixed powder for kneading. After mixing evenly, add 72.7 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, carry out extrusion molding. Extrude a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 450 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 123.2 N / cm, and the breakthrough chlorine capacity is 35%.

[0026] Example 4

[0027] Weigh 11.1 g of γ-alumina slag material crushed into 200-mesh powder, and weigh 52.2 g of pseudo-boehmite. Mix the two powders, add 0.5 g of hydroxypropyl methylcellulose and 0.5 g of polyvinyl alcohol. After mixing evenly, add 1.5 g of 65% nitric acid to 100 g of water, then add the mixed powder for kneading. After mixing evenly, add 72.7 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, carry out extrusion molding. Extrude a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 550 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 131.5 N / cm, and the breakthrough chlorine capacity is 35%.

[0028] Example 5

[0029] Weigh 27.8 g of γ-alumina slag material crushed into 200-mesh powder, and weigh 29.9 g of pseudo-boehmite. Mix the two powders, add 2.5 g of hydroxypropyl methylcellulose and 3.5 g of polyvinyl alcohol. After mixing evenly, add 4.6 g of 65% nitric acid to 100 g of water, then add the mixed powder for kneading. After mixing evenly, add 72.7 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, carry out extrusion molding. Extrude a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 450 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 143.7 N / cm, and the breakthrough chlorine capacity is 37%.

[0030] Example 6

[0031] Weigh 27.8 g of γ-alumina slag material crushed into 200-mesh powder, and weigh 29.9 g of pseudo-boehmite. Mix the two powders, add 2.5 g of hydroxypropyl methylcellulose and 3.5 g of polyvinyl alcohol. After mixing evenly, add 4.6 g of 65% nitric acid to 100 g of water, and then add the mixed powder for kneading. After mixing evenly, add 72.7 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, carry out extrusion molding. Extrude into a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 550 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 147.5 N / cm, and the breakthrough chlorine capacity is 37%.

[0032] Example 7

[0033] Weigh 27.8 g of γ-alumina slag material crushed into 200-mesh powder, and weigh 29.9 g of pseudo-boehmite. Mix the two powders, add 0.5 g of hydroxypropyl methylcellulose and 0.5 g of polyvinyl alcohol. After mixing evenly, add 1.5 g of 65% nitric acid to 100 g of water, and then add the mixed powder for kneading. After mixing evenly, add 72.7 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, carry out extrusion molding. Extrude into a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 450 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 104.3 N / cm, and the breakthrough chlorine capacity is 37%.

[0034] Example 8

[0035] Weigh 27.8 g of γ-alumina slag material crushed into 200-mesh powder, and weigh 29.9 g of pseudo-boehmite. Mix the two powders, add 0.5 g of hydroxypropyl methylcellulose and 0.5 g of polyvinyl alcohol. After mixing evenly, add 1.5 g of 65% nitric acid to 100 g of water, and then add the mixed powder for kneading. After mixing evenly, add 72.7 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, carry out extrusion molding. Extrude into a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 550 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 103.9 N / cm, and the breakthrough chlorine capacity is 37%.

[0036] Example 9

[0037] Weigh 11.1 g of γ-aluminum oxide slag material crushed into 200-mesh powder, weigh 22.4 g of pseudo-boehmite, mix the two powders, add 2.5 g of hydroxypropyl methylcellulose and 3.5 g of polyvinyl alcohol. After mixing evenly, add 4.6 g of 65% nitric acid to 100 g of water, then add the mixed powder for kneading. After mixing evenly, add 99.1 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, carry out extrusion molding. Extrude a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 450 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 124.3 N / cm, and the breakthrough chlorine capacity is 55%.

[0038] Example 10

[0039] Weigh 11.1 g of γ-aluminum oxide slag material crushed into 200-mesh powder, weigh 22.4 g of pseudo-boehmite, mix the two powders, add 2.5 g of hydroxypropyl methylcellulose and 3.5 g of polyvinyl alcohol. After mixing evenly, add 4.6 g of 65% nitric acid to 100 g of water, then add the mixed powder for kneading. After mixing evenly, add 99.1 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, carry out extrusion molding. Extrude a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 550 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 129.1 N / cm, and the breakthrough chlorine capacity is 54%.

[0040] Example 11

[0041] Weigh 22.2 g of γ-aluminum oxide slag material crushed into 200-mesh powder, weigh 7.5 g of pseudo-boehmite, mix the two powders, add 2.5 g of hydroxypropyl methylcellulose and 3.5 g of polyvinyl alcohol. After mixing evenly, add 4.6 g of 65% nitric acid to 100 g of water, then add the mixed powder for kneading. After mixing evenly, add 99.1 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, carry out extrusion molding. Extrude a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 450 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 99.8 N / cm, and the breakthrough chlorine capacity is 54%.

[0042] Example 12

[0043] Weigh 22.2 g of γ-alumina slag material crushed into 200-mesh powder, weigh 7.5 g of pseudo-boehmite, mix the two powders, add 2.5 g of hydroxypropyl methylcellulose and 3.5 g of polyvinyl alcohol. After mixing evenly, add 4.6 g of 65% nitric acid to 100 g of water, then add the mixed powder for kneading. After mixing evenly, add 99.1 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, perform extrusion molding. Extrude into a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 550 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 96.3 N / cm, and the breakthrough chlorine capacity is 51%.

[0044] Example 13

[0045] Weigh 11.1 g of γ-alumina slag material crushed into 200-mesh powder, weigh 22.4 g of pseudo-boehmite, mix the two powders, add 0.5 g of hydroxypropyl methylcellulose and 0.5 g of polyvinyl alcohol. After mixing evenly, add 1.5 g of 65% nitric acid to 100 g of water, then add the mixed powder for kneading. After mixing evenly, add 99.1 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, perform extrusion molding. Extrude into a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 450 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 113.8 N / cm, and the breakthrough chlorine capacity is 53%.

[0046] Example 14

[0047] Weigh 11.1 g of γ-alumina slag material crushed into 200-mesh powder, weigh 22.4 g of pseudo-boehmite, mix the two powders, add 0.5 g of hydroxypropyl methylcellulose and 0.5 g of polyvinyl alcohol. After mixing evenly, add 1.5 g of 65% nitric acid to 100 g of water, then add the mixed powder for kneading. After mixing evenly, add 99.1 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, perform extrusion molding. Extrude into a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 550 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 109.4 N / cm, and the breakthrough chlorine capacity is 52%.

[0048] Example 15

[0049] Weigh 22.2 g of γ-alumina slag material crushed into 200-mesh powder, weigh 7.5 g of pseudo-boehmite, mix the two powders, add 0.5 g of hydroxypropyl methylcellulose and 0.5 g of polyvinyl alcohol. After mixing evenly, add 1.5 g of 65% nitric acid to 100 g of water, then add the mixed powder for kneading. After mixing evenly, add 99.1 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, carry out extrusion molding. Extrude into a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 450 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 79.3 N / cm, and the breakthrough chlorine capacity is 55%.

[0050] Example 16

[0051] Weigh 22.2 g of γ-alumina slag material crushed into 200-mesh powder, weigh 7.5 g of pseudo-boehmite, mix the two powders, add 0.5 g of hydroxypropyl methylcellulose and 0.5 g of polyvinyl alcohol. After mixing evenly, add 1.5 g of 65% nitric acid to 100 g of water, then add the mixed powder for kneading. After mixing evenly, add 99.1 g of calcium hydroxide and mix again. After mixing to a suitable state for extrusion, carry out extrusion molding. Extrude into a strip-shaped dechlorination agent with the required diameter. The dechlorination agent is dried at 120 °C for 2 hours and calcined at 550 °C for 4 hours to obtain the finished dechlorination agent. The strength of the dechlorination agent reaches 81.2 N / cm, and the breakthrough chlorine capacity is 56%.

Claims

1. A high-temperature dechlorination agent, characterized in that, it comprises calcium hydroxide, alumina slag, pseudo-boehmite, and an auxiliary agent.

2. The high-temperature dechlorination agent according to claim 1, characterized in that, the auxiliary agent comprises one or more of hydroxypropyl methylcellulose, polyvinyl alcohol, and nitric acid.

3. The high-temperature dechlorination agent according to claim 1, characterized in that, the alumina slag is γ-crystalline alumina slag.

4. The high-temperature dechlorination agent according to claim 1, characterized in that, calcium oxide is 55 - 75 parts by weight, γ-crystalline alumina slag is 10 - 25 parts by weight, pseudo-boehmite is 5 - 35 parts by weight, and the auxiliary agent is 2 - 9 parts by weight.

5. A preparation method of a high-temperature dechlorination agent, characterized in that, by mixing pseudo-boehmite and an auxiliary agent, kneading, rolling, extruding, drying, and roasting calcium hydroxide and alumina slag, the dechlorination agent is made.

6. The preparation method of the high-temperature dechlorination agent according to claim 5, characterized in that, the drying temperature is 120 °C.

7. The preparation method of the high-temperature dechlorination agent according to claim 5, characterized in that, the drying time is 2 hours.

8. The preparation method of the high-temperature dechlorination agent according to claim 5, characterized in that, the roasting temperature is 450 - 550 °C.

9. The preparation method of the high-temperature dechlorination agent according to claim 5, characterized in that, the roasting time is 4 hours.