Method for recycling of catalyst waste of diethylbenzene dehydrogenation and diethylbenzene dehydrogenation catalyst

Abstract

The present application relates to the field of catalyst preparation, and discloses a method for recycling diethylbenzene dehydrogenation catalyst waste and a diethylbenzene dehydrogenation catalyst.The method for recycling diethylbenzene dehydrogenation catalyst waste comprises the following steps: 1) mixing diethylbenzene dehydrogenation catalyst waste with water; and 2) mixing, kneading, shaping, drying and calcining the material obtained in step 1) with a binder to obtain a diethylbenzene dehydrogenation catalyst; wherein the diethylbenzene dehydrogenation catalyst waste is solid waste generated in the production process of the diethylbenzene dehydrogenation catalyst.The method can recycle the waste generated in the production process of the diethylbenzene dehydrogenation catalyst, and diethylbenzene dehydrogenation catalyst meeting the quality requirements can be prepared, so that the purposes of reducing material loss, reducing production cost, saving resources and protecting the environment are achieved.

Description

Technical Field

[0001] This invention relates to the field of catalyst preparation, specifically to a method for recycling waste from diethylbenzene dehydrogenation catalysts and a diethylbenzene dehydrogenation catalyst. Background Technology

[0002] Diethylbenzene dehydrogenation catalysts are mainly used in the catalytic reaction of diethylbenzene dehydrogenation to divinylbenzene. These catalysts are strip-shaped cylindrical granular catalysts, and their main preparation processes include mixing, extrusion, pelletizing, drying, and calcination. Each process generates small catalyst lumps and fine particles to varying degrees, resulting in relatively high material loss throughout the production process. Furthermore, the lost material can only be treated as solid waste, leading to high production costs and significant environmental emission pressure. Currently, the diethylbenzene dehydrogenation catalyst preparation process generates approximately 8% waste, indicating relatively high losses and the incurred costs of solid waste treatment. Therefore, it is essential to reuse this waste, which is crucial for reducing production costs and alleviating environmental emission pressure. This also provides valuable experience for the reuse of waste from other solid particulate catalysts. Summary of the Invention

[0003] The purpose of this invention is to overcome the problems of high waste generation, high material loss, high production costs, and environmental pollution in the existing production process of diethylbenzene dehydrogenation catalysts. This invention provides a method for recycling waste from diethylbenzene dehydrogenation catalysts and a corresponding diethylbenzene dehydrogenation catalyst. The method of this invention can reuse the waste generated during the production of diethylbenzene dehydrogenation catalysts to produce diethylbenzene dehydrogenation catalysts that meet quality requirements, thereby reducing material loss, lowering production costs, conserving resources, and protecting the environment.

[0004] To achieve the above objectives, the present invention provides a method for recycling diethylbenzene dehydrogenation catalyst waste, the method comprising the following steps:

[0005] 1) Mix the waste diethylbenzene dehydrogenation catalyst with water;

[0006] 2) The material obtained in step 1) is mixed with a binder, molded, dried and calcined to obtain a diethylbenzene dehydrogenation catalyst;

[0007] The diethylbenzene dehydrogenation catalyst waste is solid waste generated during the production of diethylbenzene dehydrogenation catalyst.

[0008] Preferably, the particle size of the diethylbenzene dehydrogenation catalyst waste is 4.2-4.8 mm.

[0009] Preferably, in step 2), the binder is one or more of carboxymethyl cellulose, guar gum powder, kaolin, and cement.

[0010] Preferably, in step 2), the weight ratio of the binder to the diethylbenzene dehydrogenation catalyst waste is 1:160-500, more preferably 1:200-320.

[0011] Preferably, the mixing conditions include a weight ratio of the diethylbenzene dehydrogenation catalyst waste to water of 5-6.4:1, more preferably 5.3-6:1.

[0012] Preferably, the mixing conditions include a mixing time of 1.5-2.5 hours.

[0013] Preferably, in step 2), the kneading time is 20-45 minutes, more preferably 25-35 minutes.

[0014] Preferably, the drying conditions include: a drying temperature of 30-120°C and a drying time of 12-26 hours.

[0015] Preferably, the calcination conditions include: a calcination temperature of 150-850℃ and a calcination time of 12-22 hours.

[0016] According to another aspect of the present invention, a diethylbenzene dehydrogenation catalyst prepared by the recycling method described herein is provided.

[0017] This invention involves mixing waste materials such as lumpy materials and fine particles generated during various stages of the diethylbenzene dehydrogenation catalyst production process with water, and then fully kneading, molding, drying, and calcining them with a binder to activate them. This process allows waste materials that would otherwise be treated as solid waste to be reused to produce diethylbenzene dehydrogenation catalysts that meet quality requirements. This reduces material loss, lowers production costs, alleviates environmental emission pressure, and achieves excellent results. Detailed Implementation

[0018] According to the present invention, a method for recycling diethylbenzene dehydrogenation catalyst waste is provided, wherein the method includes the following steps:

[0019] 1) Mix the waste diethylbenzene dehydrogenation catalyst with water;

[0020] 2) The material obtained in step 1) is mixed with a binder, molded, dried and calcined to obtain a diethylbenzene dehydrogenation catalyst;

[0021] The diethylbenzene dehydrogenation catalyst waste is a solid waste generated during the production and preparation of the diethylbenzene dehydrogenation catalyst.

[0022] In this invention, the waste material of the diethylbenzene dehydrogenation catalyst can be the waste material from the molding and / or drying and / or calcination process during the production and preparation of the diethylbenzene dehydrogenation catalyst, wherein the waste material from the molding and drying process is preferred.

[0023] According to the present invention, since the present invention uses the waste generated during the production and preparation of the above-mentioned diethylbenzene dehydrogenation catalyst, which contains the active components required for the catalyst, the method of the present invention enables the waste that was originally treated as solid waste to be reused to produce diethylbenzene dehydrogenation catalyst that meets the quality requirements, thereby reducing material loss, reducing production costs, alleviating environmental emission pressure, and achieving excellent results.

[0024] The method of this invention involves mixing diethylbenzene dehydrogenation catalyst waste with water, then kneading, molding, drying, and calcining it together with a binder to prepare a diethylbenzene dehydrogenation catalyst that meets the requirements, thereby achieving the recycling of diethylbenzene dehydrogenation catalyst waste.

[0025] According to a preferred embodiment of the present invention, in order to achieve good recycling effect, the particle size of the diethylbenzene dehydrogenation catalyst waste is 4.2-4.8 mm, more preferably 4.35-4.55 mm.

[0026] According to a preferred embodiment of the present invention, in order to ensure thorough mixing, the mixing conditions include: a mixing time of 1.5-2.5 hours; preferably, a mixing time of 1.8-2.2 hours. The mixing temperature can be room temperature, for example, 5-40°C.

[0027] Furthermore, the preferred weight ratio of the diethylbenzene dehydrogenation catalyst waste to water is 5-6.4:1, more preferably 5.3-6:1. Mixing under these conditions allows the material to be fully softened, resulting in a sludge-like mixture free of obvious hard particles.

[0028] According to the present invention, the binder is not particularly limited and can be any existing binder used for preparing diethylbenzene dehydrogenation catalysts, for example, selected from one or more of carboxymethyl cellulose, guar gum, kaolin and cement.

[0029] According to the present invention, in order to prepare a diethylbenzene dehydrogenation catalyst with excellent catalytic performance, the weight ratio of the diethylbenzene dehydrogenation catalyst waste to the binder can be 1:160-500, preferably 1:200-320. By controlling the proportion of the binder, the crush resistance of the obtained diethylbenzene dehydrogenation catalyst can be further improved.

[0030] In this invention, the conditions for mixing, molding, drying and calcining are not particularly limited, and existing conditions for preparing diethylbenzene dehydrogenation catalysts can be used.

[0031] The kneading process can be carried out using devices such as a horizontal kneader with two stirring paddles or a vacuum pumice machine with two spiral shafts. The kneading conditions may include a kneading time of 20-45 minutes, preferably 25-35 minutes. Furthermore, the kneading temperature can be, for example, 50-75°C, preferably 60-70°C.

[0032] Through the molding process, catalysts of desired shapes such as flakes, spheres, microspheres, and strips can be obtained. The molding method can be extrusion molding, compression molding, roll forming, etc., as long as the desired catalyst shape is obtained.

[0033] The drying conditions may include: a drying temperature of 30-120°C and a drying time of 12-26 hours; preferably, a drying temperature of 40-110°C and a drying time of 18-24 hours. After drying, the catalyst can be further cut to obtain a product of the desired particle size.

[0034] The roasting can be carried out using a roller kiln, rotary kiln, or similar method. The roasting conditions may include a roasting temperature of 150-850℃ and a roasting time of 12-22 hours.

[0035] The present invention also provides a diethylbenzene dehydrogenation catalyst prepared by the above-described recycling method. The diethylbenzene dehydrogenation catalyst has a conversion rate of 72% or higher, a selectivity of 95% or higher, a yield of 68.4% or higher, and a crushing resistance of 175.0 N / 5 mm or higher.

[0036] The present invention will be described in detail below through embodiments. In the following embodiments, the crushing force was measured by the HG / T2782-2011 method.

[0037] Diethylbenzene dehydrogenation catalyst waste refers to the waste generated during the molding, drying, and calcination processes in the production and preparation of diethylbenzene dehydrogenation catalyst, with a particle size of 4.2-4.8 mm.

[0038] Example 1

[0039] Weigh 300g of diethylbenzene dehydrogenation catalyst waste, mix it in 55g of pure water for 2 hours, add 1.5g of carboxymethyl cellulose and knead for 30 minutes (kneading temperature is 65℃) to form a sticky, extrudable agglomerate. Then extrude it and dry it at 50℃ for 14 hours, then dry it at 100℃ for 8 hours, cut it into 8mm long particles, and then keep it at 300℃ for 3 hours and 800℃ for 4 hours to obtain the finished diethylbenzene dehydrogenation catalyst. Its crush resistance is shown in Table 1.

[0040] Example 2

[0041] Weigh 300g of diethylbenzene dehydrogenation catalyst waste, mix it in 55g of pure water for 2 hours, add 1.2g of carboxymethyl cellulose and knead for 25 minutes (kneading temperature is 65℃) to form a sticky, extrudable agglomerate. Then extrude it and dry it at 50℃ for 14 hours, then dry it at 100℃ for 8 hours, cut it into 8mm long particles, and then keep it at 300℃ for 3 hours and 800℃ for 4 hours to obtain the finished diethylbenzene dehydrogenation catalyst. Its crush resistance is shown in Table 1.

[0042] Example 3

[0043] Weigh 300g of diethylbenzene dehydrogenation catalyst waste, mix it in 55g of pure water for 2 hours, add 1g of carboxymethyl cellulose and 0.5g of cement and knead for 30 minutes (kneading temperature is 65℃) to form a sticky, extrudable lump. Then extrude it and dry it at 50℃ for 14 hours, then dry it at 100℃ for 8 hours, cut it into 8mm long particles, and then keep it at 300℃ for 3 hours and 800℃ for 4 hours to obtain the finished diethylbenzene dehydrogenation catalyst. Its crushing resistance is shown in Table 1.

[0044] Example 4

[0045] The diethylbenzene dehydrogenation catalyst was prepared using the method described in Example 1, except that the mixing time was 1.5 hours. The crushing resistance of the resulting diethylbenzene dehydrogenation catalyst is shown in Table 1.

[0046] Example 5

[0047] The diethylbenzene dehydrogenation catalyst was prepared using the method described in Example 1, except that the mixing time was 2.5 hours. The crushing resistance of the resulting diethylbenzene dehydrogenation catalyst is shown in Table 1.

[0048] Example 6

[0049] The diethylbenzene dehydrogenation catalyst was prepared using the method described in Example 1, except that 50g of pure water was used in the mixture. The crushing resistance of the finished diethylbenzene dehydrogenation catalyst is shown in Table 1.

[0050] Test Example 1

[0051] 100 ml of catalyst was loaded into the reactor and the reaction was carried out at atmospheric pressure and a diethylbenzene liquid hourly space velocity of 1.0 hr. -1 The activity was evaluated under the conditions of 620℃ and water ratio (wt) 2.0, and the evaluation results are listed in Table 1.

[0052] Diethylbenzene conversion rate % = (Infeed diethylbenzene weight flow rate - Discharge diethylbenzene weight flow rate) / (Infeed diethylbenzene weight flow rate) × 100%

[0053] Divinylbenzene selectivity % = (Divinylbenzene production weight flow rate) / (Infeed diethylbenzene weight flow rate - Discharge diethylbenzene weight flow rate) × 100%

[0054] Divinylbenzene yield % = Diethylbenzene conversion % × Divinylbenzene selectivity %

[0055] Table 1

[0056]

[0057] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for recycling waste from diethylbenzene dehydrogenation catalysts, characterized in that, The method includes the following steps: 1) Mix the diethylbenzene dehydrogenation catalyst waste with water; 2) The material obtained in step 1) is mixed with a binder, kneaded, shaped, dried and calcined to obtain a diethylbenzene dehydrogenation catalyst; The diethylbenzene dehydrogenation catalyst waste refers to the waste generated during the molding and / or drying and / or calcination processes in the production and preparation of the diethylbenzene dehydrogenation catalyst. The particle size of the diethylbenzene dehydrogenation catalyst waste is 4.2-4.8 mm. In step 2), the weight ratio of the binder to the diethylbenzene dehydrogenation catalyst waste is 1:160-320. The binder is one or more of carboxymethyl cellulose, guar gum powder, kaolin, and cement. The mixing conditions include a weight ratio of diethylbenzene dehydrogenation catalyst waste to water of 5-6.4:

1. The mixing time is 20-45 minutes, and the calcination conditions include: calcination temperature of 300-850℃ and calcination time of 12-22 hours.

2. The reuse method according to claim 1, wherein, In step 2), the weight ratio of the binder to the diethylbenzene dehydrogenation catalyst waste is 1:200-320.

3. The reuse method according to claim 1, wherein, The mixing conditions include a weight ratio of 5.3-6:1 between the diethylbenzene dehydrogenation catalyst waste and water.

4. The reuse method according to claim 1, wherein, The mixing conditions include a mixing time of 1.5-2.5 hours.

5. The reuse method according to claim 1, wherein, In step 2), the mixing time is 25-35 minutes.

6. The reuse method according to claim 1 or 2, wherein, The drying conditions include: a drying temperature of 30-120℃ and a drying time of 12-26 hours.

7. The diethylbenzene dehydrogenation catalyst prepared by the recycling method according to any one of claims 1-6.

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