Drying agent prepared from catalyst slag and preparation method thereof
By combining the gamma crystal alumina slag with porous materials and adding additives to prepare high-efficiency desiccants, the problem of poor molding performance of the catalyst slag is solved, and the preparation of desiccants with high efficiency adsorption and good stability is achieved, reducing raw material costs and meeting environmental protection requirements.
Patent Information
- Application Number
- CN202311591654.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-11-27
- Publication Date
- 2025-05-27
AI Technical Summary
The viscosity of gamma-type alumina slag produced during the catalyst production process decreases, is difficult to form, and is difficult to reuse in the original catalyst, resulting in additional treatment costs and environmental pollution.
Highly efficient desiccant is prepared by combining gamma crystal alumina slag with porous materials such as pseudo-thin aluminite or silica gel powder, and adding additives such as hydroxypropyl methylcellulose, polyvinyl alcohol, and nitric acid.
The prepared desiccant has high lateral pressure strength and static adsorption capacity, reaching more than 70N/cm and more than 20, realizing the secondary utilization of catalyst slag material, reducing raw material costs, and meeting the technical requirements of green and environmental protection.
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of desiccants, and relates to a desiccant prepared from catalyst slag and a preparation method thereof, which are mainly applied to the drying of instrument air and industrial air. Background Art
[0002] Desiccants for instrument air and industrial air are used to remove moisture generated during the compression of air to avoid low-temperature freezing. Desiccants are mainly divided into physical adsorption desiccants and chemical adsorption desiccants. Physical adsorption mainly uses the pore structure of the desiccant itself to adsorb moisture, and the water absorption is reversible, which is commonly used in industrial production and daily life; chemical adsorption mainly combines with water through its own components to form a stable structure, and the water absorption is irreversible.
[0003] Common desiccants are mainly made from raw materials such as alumina, molecular sieve, and silica gel. Utilizing the characteristics of good stability and easy molding of the above raw materials, strip-shaped or spherical desiccants are prepared. The desiccants mainly rely on physical adsorption. After being saturated with water absorption, the adsorbed moisture can be removed through regeneration and can be recycled multiple times, with excellent service life. Alumina desiccants mainly use x-ρ type alumina or aluminum hydroxide as the main raw materials, which have good viscosity when mixed with water, facilitating forming operations such as extrusion and rolling into balls. γ-crystalline alumina is relatively expensive and is less used in the production of desiccants.
[0004] During the production process of catalysts, γ-alumina slag is generated. The viscosity of this solid slag decreases, making it difficult to re-form and difficult to apply to the original catalyst. This solid slag not only requires additional treatment costs, but also the solid waste discharge will have an impact on the environment. Summary of the Invention
[0005] In order to solve the technical problems existing in the prior art, the present invention mainly utilizes γ-crystalline alumina and other porous materials generated during the catalyst production process, adds appropriate additives to improve its forming performance, and prepares an industrial air and instrument air desiccant with excellent adsorption effect and good stability. At the same time, the raw material cost is reduced and the market competitiveness is enhanced. Through this technology, the secondary utilization of catalyst slag is completed, meeting the technical requirements of environmental protection.
[0006] The above object of the present invention is achieved by the following technical solutions:
[0007] A desiccant prepared from catalyst slag, comprising γ-crystalline alumina slag, porous material, and additive.
[0008] Further, the porous material is pseudo-boehmite or silica powder or a mixture of the two.
[0009] Further, the additives include hydroxypropyl methylcellulose, polyvinyl alcohol, and nitric acid.
[0010] Further, the γ-alumina slag is 50-100 parts by weight, the pseudo-boehmite is 0-50 parts by weight, the silica powder is 0-50 parts by weight, and the auxiliary agent is 2-9 parts by weight.
[0011] A preparation method of a desiccant prepared using catalyst slag. The γ-alumina slag is compounded with other porous materials, an auxiliary agent is added, and then kneading, rolling, extrusion, drying, and roasting are carried out to obtain the desiccant.
[0012] Further, the drying temperature is 110 °C.
[0013] Further, the drying time is 2 hours.
[0014] Further, the roasting temperature is 450-600 °C.
[0015] Further, the roasting time is 4 hours.
[0016] The beneficial effects of the present invention compared with the prior art are as follows:
[0017] The solid waste of alumina slag generated in the catalyst production process is added with an appropriate auxiliary agent to improve its forming performance, and an alumina desiccant is prepared. The side compression strength of the desiccant reaches more than 70 N / cm, the highest strength reaches more than 160 N / cm, the static adsorption reaches more than 20, and the highest static adsorption value reaches more than 24. Specific Embodiments
[0018] The present invention will be described in detail below through specific examples, but the protection scope of the present invention is not limited. Unless otherwise specified, the experimental methods used in the present invention are all conventional methods, and the experimental equipment, materials, reagents, etc. used can all be obtained from commercial channels.
[0019] The present invention uses one or several porous materials such as γ-alumina slag, pseudo-boehmite, and silica powder as the main components, and adds a certain proportion of auxiliary agents, including hydroxypropyl methylcellulose, polyvinyl alcohol, and nitric acid. Among them, the γ-alumina slag is 50-100 parts by weight, the pseudo-boehmite is 0-50 parts by weight, the silica powder is 0-50 parts by weight, and the auxiliary agent is 2-9 parts by weight. The γ-alumina slag with poor viscosity that has been roasted is compounded with other porous materials, assisted by an auxiliary agent, and then kneaded, rolled, extruded, dried at 110 °C for 2 hours, and roasted at 450-600 °C for 4 hours to obtain the desiccant.
[0020] Comparative Example 1
[0021] Weigh 54.4 g of silica gel powder, crush γ-aluminum oxide into a 200-mesh powder, weigh 50.5 g of pseudo-boehmite powder, weigh 14.5 g. Mix the three powders, add 2 g of hydroxypropyl methylcellulose and 2 g of polyvinyl alcohol. After mixing evenly, add 3.1 g of 65% nitric acid to 100 g of water, then add the mixed powders for kneading. After mixing evenly, extrude into bar-shaped desiccants with the required diameter. The desiccants are dried at 110 °C for 2 hours and calcined at 550 °C for 4 hours to obtain the finished desiccants. The strength of the desiccants reaches 150.8 N / cm, and the static adsorption value is 23.2.
[0022] Example 1
[0023] Weigh 68.0 g of silica gel powder, crush γ-aluminum oxide into a 200-mesh powder, weigh 50.5 g. 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 powders for kneading. After mixing evenly, extrude into bar-shaped desiccants with the required diameter. The desiccants are dried at 110 °C for 2 hours and calcined at 600 °C for 4 hours to obtain the finished desiccants. The strength of the desiccants reaches 80.3 N / cm, and the static adsorption value is 23.8.
[0024] Example 2
[0025] Weigh 72.6 g of pseudo-boehmite powder, crush γ-aluminum oxide into a 200-mesh powder, weigh 50.5 g. 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 powders for kneading. After mixing evenly, extrude into bar-shaped desiccants with the required diameter. The desiccants are dried at 110 °C for 2 hours and calcined at 600 °C for 4 hours to obtain the finished desiccants. The strength of the desiccants reaches 169.4 N / cm, and the static adsorption value is 20.7.
[0026] Example 3
[0027] Weigh 68.0 g of silica gel powder, crush γ-aluminum oxide into a 200-mesh powder, weigh 50.5 g. Mix the two powders, add 3.5 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 powders for kneading. After mixing evenly, extrude into bar-shaped desiccants with the required diameter. The desiccants are dried at 110 °C for 2 hours and calcined at 600 °C for 4 hours to obtain the finished desiccants. The strength of the desiccants reaches 100.6 N / cm, and the static adsorption value is 24.3.
[0028] Example 4
[0029] Weigh 72.6 g of pseudo-boehmite powder. Crush γ-alumina into a 200-mesh powder and weigh 50.5 g. Mix the two powders, add 3.5 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 and knead. After mixing evenly, extrude into a bar-shaped desiccant with the required diameter. The desiccant is dried at 110 °C for 2 hours and calcined at 600 °C for 4 hours to obtain the finished desiccant. The strength of the desiccant reaches 186.2 N / cm, and the static adsorption value is 21.1.
[0030] Example 5
[0031] Crush γ-alumina into a 200-mesh powder and weigh 101 g. Add 3.5 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 and knead. After mixing evenly, extrude into a bar-shaped desiccant with the required diameter. The desiccant is dried at 110 °C for 2 hours and calcined at 600 °C for 4 hours to obtain the finished desiccant. The strength of the desiccant reaches 100.3 N / cm, and the static adsorption value is 21.2.
[0032] Example 6
[0033] Crush γ-alumina into a 200-mesh powder and weigh 101 g. 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 and knead. After mixing evenly, extrude into a bar-shaped desiccant with the required diameter. The desiccant is dried at 110 °C for 2 hours and calcined at 600 °C for 4 hours to obtain the finished desiccant. The strength of the desiccant reaches 70.4 N / cm, and the static adsorption value is 20.5.
[0034] Example 7
[0035] Weigh 68.0 g of silica gel powder. Crush γ-alumina into a 200-mesh powder and weigh 50.5 g. 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 and knead. After mixing evenly, extrude into a bar-shaped desiccant with the required diameter. The desiccant is dried at 110 °C for 2 hours and calcined at 450 °C for 4 hours to obtain the finished desiccant. The strength of the desiccant reaches 75.1 N / cm, Example 8
[0036] Weigh 72.6 g of pseudo-boehmite powder. Crush γ-aluminum oxide into a 200-mesh powder and weigh 50.5 g. 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, carry out extrusion molding. Extrude into a bar-shaped desiccant with the required diameter. The desiccant is dried at 110 °C for 2 hours and calcined at 450 °C for 4 hours to obtain the finished desiccant. The strength of the desiccant reaches 158.2 N / cm, and the static adsorption value is 20.1.
[0037] Example 9
[0038] Weigh 68.0 g of silica gel powder. Crush γ-aluminum oxide into a 200-mesh powder and weigh 50.5 g. Mix the two powders, add 3.5 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, carry out extrusion molding. Extrude into a bar-shaped desiccant with the required diameter. The desiccant is dried at 110 °C for 2 hours and calcined at 450 °C for 4 hours to obtain the finished desiccant. The strength of the desiccant reaches 99.2 N / cm, and the static adsorption value is 23.8.
[0039] Example 10
[0040] Weigh 72.6 g of pseudo-boehmite powder. Crush γ-aluminum oxide into a 200-mesh powder and weigh 50.5 g. Mix the two powders, add 3.5 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, carry out extrusion molding. Extrude into a bar-shaped desiccant with the required diameter. The desiccant is dried at 110 °C for 2 hours and calcined at 450 °C for 4 hours to obtain the finished desiccant. The strength of the desiccant reaches 164.2 N / cm, and the static adsorption value is 20.6.
[0041] Example 11
[0042] Crush γ-aluminum oxide into a 200-mesh powder and weigh 101 g. Add 3.5 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, carry out extrusion molding. Extrude into a bar-shaped desiccant with the required diameter. The desiccant is dried at 110 °C for 2 hours and calcined at 450 °C for 4 hours to obtain the finished desiccant. The strength of the desiccant reaches 100.5 N / cm, and the static adsorption value is 21.8.
[0043] Example 12
[0044] 101 g of γ-alumina in crystalline form is ground into a powder of 200 mesh, 0.5 g of hydroxypropyl methylcellulose and 0.5 g of polyvinyl alcohol are added, and after mixing evenly, 1.5 g of 65% nitric acid is added to 100 g of water, and then the mixed powder is added for kneading. After mixing evenly, it is extruded into strips. The extruded strips are desiccants with the required diameter. The desiccants are dried at 110 °C for 2 hours and calcined at 450 °C for 4 hours to obtain the finished desiccants. The strength of the desiccants reaches 71.2 N / cm, and the static adsorption value is 20.7.
[0045] The above-described embodiments are only the preferred embodiments of the present invention, and not all the feasible embodiments of the present invention. For those of ordinary skill in the art, any obvious changes made without departing from the principles and spirit of the present invention should be considered to be included within the scope of protection of the claims of the present invention.
Claims
1. A desiccant prepared using catalyst slag, characterized in that, it comprises alumina slag of γ crystal form, porous material, and additives.
2. The desiccant prepared using catalyst slag according to claim 1, characterized in that, the porous material is pseudo-boehmite or silica powder or a mixture of the two.
3. The desiccant prepared using catalyst slag according to claim 1, characterized in that, the additives include hydroxypropyl methylcellulose, polyvinyl alcohol, and nitric acid.
4. The desiccant prepared using catalyst slag according to claim 1, characterized in that, the alumina slag of γ crystal form is 50 - 100 parts by weight, pseudo-boehmite is 0 - 50 parts by weight, silica powder is 0 - 50 parts by weight, and the additives are 2 - 9 parts by weight.
5. A preparation method of a desiccant prepared using catalyst slag, characterized in that, the alumina slag of γ crystal form is compounded with other porous materials, additives are added, and then kneading, rolling, extrusion, drying, and calcination are carried out to obtain the desiccant.
6. The preparation method of a desiccant prepared using catalyst slag according to claim 5, characterized in that, the drying temperature is 110 °C.
7. The preparation method of a desiccant prepared using catalyst slag according to claim 5, characterized in that, the drying time is 2 hours.
8. The preparation method of a desiccant prepared using catalyst slag according to claim 5, characterized in that, the calcination temperature is 450 - 600 °C.
9. The preparation method of a desiccant prepared using catalyst slag according to claim 5, characterized in that, the calcination time is 4 hours.