阅读说明：本技术 一种脱金属催化剂的制备方法 (Preparation method of demetallization catalyst ) 是由 季洪海 凌凤香 王少军 张会成 沈智奇 于 2019-04-18 设计创作，主要内容包括：本发明公开了一种脱金属催化剂的制备方法,包括如下内容：(1)将废加氢处理催化剂粉碎,然后焙烧处理；(2)将步骤(1)所得的物料浸入碳酸氢铵水溶液中密封热处理,过滤,物料经干燥,然后用聚乙二醇溶液浸泡,过滤,干燥,得到预处理物料A；(3)将拟薄水铝石与预处理物料A混捏成型,成型物经干燥、焙烧后得到载体,将加氢活性组分负载到载体上,得到脱金属催化剂。该方法利用废催化剂制备加氢脱金属催化剂,降低生产成本的同时减少环境污染,该加氢脱金属催化剂既保证了催化剂的活性,同时又使催化剂具有良好的稳定性,可延长装置的运转周期。(The invention discloses a preparation method of a demetallization catalyst, which comprises the following steps: (1) crushing the waste hydrotreating catalyst, and then roasting; (2) immersing the material obtained in the step (1) in an ammonium bicarbonate aqueous solution, sealing, performing heat treatment, filtering, drying the material, then immersing the material in a polyethylene glycol solution, filtering, and drying to obtain a pretreated material A; (3) kneading and molding the pseudoboehmite and the pretreatment material A, drying and roasting the molded product to obtain a carrier, and loading the hydrogenation active component on the carrier to obtain the demetallization catalyst. The method utilizes the waste catalyst to prepare the hydrodemetallization catalyst, reduces the production cost and environmental pollution, ensures the activity of the catalyst, ensures the good stability of the catalyst, and can prolong the running period of the device.)

1. The preparation method of the demetallization catalyst is characterized by comprising the following steps of: (1) crushing the waste hydrotreating catalyst, and then roasting; (2) immersing the material obtained in the step (1) in an ammonium bicarbonate aqueous solution, sealing, performing heat treatment, filtering, drying the material, then immersing the material in a polyethylene glycol solution, filtering, and drying to obtain a pretreated material A; (3) kneading and molding the pseudoboehmite and the pretreatment material A, drying and roasting the molded product to obtain a carrier, and loading the hydrogenation active component on the carrier to obtain the demetallization catalyst.

2. The method of claim 1, wherein: the waste hydrotreating catalyst in the step (1) comprises active metal sulfide and an alumina carrier; the active metal is one or more of VIB and VIII group metals; the active metal content on the spent hydroprocessing catalyst is 1wt% to 40wt% of the weight of the catalyst.

3. The method of claim 1, wherein: the roasting temperature in the step (1) is 700-950 ℃, and the roasting time is 6-12 hours.

4. The method of claim 1, wherein: the dosage of the ammonium bicarbonate aqueous solution in the step (2) is at least that the material obtained in the step (1) is immersed; the mass percentage concentration of the ammonium bicarbonate aqueous solution is 15-25%.

5. The method of claim 1, wherein: the sealing heat treatment temperature in the step (2) is 120-180 ℃, and the treatment time is 4-8 hours.

6. The method of claim 1, wherein: the drying conditions in the step (2) are as follows: the drying temperature is 100-160 ℃, and the drying time is 6-10 hours.

7. The method of claim 1, wherein: the average molecular weight of the polyethylene glycol in the step (2) is 2000-12000, the dosage of the polyethylene glycol solution is at least to immerse the heat-treated materials, the soaking time is 1-2 hours, and the mass percent concentration of the polyethylene glycol solution is 20-40%.

8. The method of claim 1, wherein: and (3) pretreating the material A in the step (2) to form a staggered columnar structure, wherein the length of the columnar structure is 0.5-2 mu m, and the diameter of the columnar structure is 50-200 nm.

9. The method of claim 1, wherein: the mass ratio of the pretreatment material A to the pseudo-boehmite in the step (3) is 1:5-1: 2.

10. The method of claim 1, wherein: the drying temperature in the step (3) is 100-160 ℃, and the drying time is 6-10 hours; the roasting temperature is 600-750 ℃, and the roasting time is 4-6 hours.

Technical Field

The invention relates to the field of catalyst preparation, in particular to a preparation method of a hydrodemetallization catalyst.

Background

With the deterioration and heaviness of crude oil, the efficient conversion of heavy oil and the improvement of the yield of light oil products become an important trend in the development of oil refining technology. The residue fixed bed hydrogenation technology is an effective means for realizing the high-efficiency conversion of heavy oil. By adopting the technical route, the impurities such as metal, sulfur, nitrogen, carbon residue and the like in the residual oil can be effectively removed, high-quality feed is provided for catalytic cracking, and the strict environmental protection regulation requirements are met while the yield of light oil products is increased. During the processing of heavy oil, the metal compounds in the heavy oil are decomposed, and metal impurities are deposited on the inner surface and the outer surface of the catalyst to block the pore channels, so that the catalyst is even poisoned and deactivated.

In the using process of the catalyst, the catalyst becomes waste due to the loss of the original activity, and the waste catalyst rich in metal is not used, so that resources are wasted and the environment is polluted. Recently, environmental regulations have become more stringent for the disposal of spent catalysts. The waste catalyst is treated by several methods, such as landfill treatment, metal recovery, regeneration or recycling, and is used as a raw material to generate other useful products to solve the problem of the waste catalyst.

CN102441440A discloses a method for preparing a hydrotreating catalyst from a spent catalyst. Grinding the waste hydrotreating catalyst, adding alumina, a binder, an acid solution or an alkaline solution and other raw materials into the ground powder, kneading, molding, drying and roasting the molded sample to obtain the new hydrotreating catalyst. Although the method utilizes the waste catalyst to prepare the new hydrotreating catalyst, the pore volume of the catalyst needs to be further improved.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a preparation method of a demetallization catalyst. The method utilizes the waste catalyst to prepare the hydrodemetallization catalyst, reduces the production cost and environmental pollution, ensures the activity of the catalyst, ensures the good stability of the catalyst, and can prolong the running period of the device.

The preparation method of the demetallization catalyst comprises the following steps:

(1) crushing the waste hydrotreating catalyst, and then roasting;

(2) immersing the material obtained in the step (1) in an ammonium bicarbonate aqueous solution, sealing, performing heat treatment, filtering, drying the material, then immersing the material in a polyethylene glycol solution, filtering, and drying to obtain a pretreated material A;

(3) kneading and molding the pseudoboehmite and the pretreatment material A, drying and roasting the molded product to obtain a carrier, and loading the hydrogenation active component on the carrier to obtain the demetallization catalyst.

In the method of the present invention, the spent hydrotreating catalyst in step (1) refers to a hydrotreating catalyst such as hydrodesulfurization, denitrification, etc. of distillate oil and residual oil which has not achieved the reaction requirement or has not been completely deactivated due to gradation. The hydrotreating catalyst contains hydrogenation active metal, the active metal is one or more of VIB and VIII group metals, and the waste hydrotreating catalyst contains sulfide and alumina of the active metal, and also contains other oxides such as titanium oxide, silicon oxide, boron oxide, molecular sieves and the like, and impurities such as carbon deposition, heavy metals and the like. The active metal content on the spent hydroprocessing catalyst is typically from 1wt% to 40wt% of the catalyst weight and the metal impurities are typically from 0.1wt% to 30 wt%. The shape is generally cylindrical, spherical or multi-lobed. The waste hydrotreating catalyst is crushed to be more than 200 meshes, and preferably 400-800 meshes. The roasting temperature is 700-950 ℃, and the roasting time is 6-12 hours.

In the method, the dosage of the ammonium bicarbonate aqueous solution in the step (2) is at least the dosage of the material obtained in the step (1) immersed; the mass percentage concentration of the ammonium bicarbonate aqueous solution is 15-25%.

In the method of the invention, the sealing heat treatment temperature in the step (2) is 120-180 ℃, preferably 120-160 ℃, and the treatment time is 4-8 hours.

In the method of the present invention, the drying conditions in step (2) are as follows: the drying temperature is 100-160 ℃, and the drying time is 6-10 hours.

In the method of the invention, the average molecular weight of the polyethylene glycol in the step (2) is 2000-12000, the dosage of the polyethylene glycol solution is at least to immerse the heat-treated material, the soaking time is 1-2 hours, and the mass percent concentration of the polyethylene glycol solution is 20-40%.

According to the method, the pretreated material A in the step (2) is of a mutually staggered columnar structure, the length of the columnar structure is 0.5-2 mu m, and the diameter of the columnar structure is 50-200 nm.

In the method, the mass ratio of the pretreatment material A in the step (3) to the pseudo-boehmite is 1:5-1: 2.

In the method of the invention, the kneading molding in the step (3) is carried out by adopting a conventional method in the field, and in the molding process, conventional molding aids, such as one or more of peptizing agents, extrusion aids and the like, can be added according to the needs. The peptizing agent is one or more of hydrochloric acid, nitric acid, sulfuric acid, acetic acid, oxalic acid and the like; the extrusion aid is sesbania powder. The drying temperature is 100-160 ℃, and the drying time is 6-10 hours; the roasting temperature is 600-750 ℃, and the roasting time is 4-6 hours; the calcination is carried out in an oxygen-containing atmosphere, preferably an air atmosphere.

In the method of the present invention, the supporting mode in the step (3) may be a mode of supporting when the carrier is kneaded, or a mode of impregnating the carrier, preferably a mode of impregnating the carrier. The adopted impregnation liquid containing the hydrogenation active metal component is a solution containing VIB group and/or VIII group metals, the VIB group metal is selected from one or more of W, Mo, the VIII group metal is selected from one or more of Co and Ni, the content of the VIB group metal is 8-15g/100mL calculated by metal oxides, the content of the VIII group metal is 2.5-4.0g/100mL calculated by metal oxides, and equal-volume impregnation or supersaturated impregnation can be adopted during impregnation. After the impregnation, drying and roasting are generally carried out, wherein the drying temperature is 80-160 ℃, the drying time is 6-10 hours, and the roasting is carried out at the temperature of 450-550 ℃ for 4-8 hours.

Compared with the prior art, the invention has the following advantages:

(1) the invention takes the waste hydrogenation catalyst as the raw material, obtains the mutually staggered columnar structure through the simple pretreatment process, forms larger through pore channels by forming with pseudo-boehmite and dispersing in a carrier, and the pore channels are mutually communicated, thereby being beneficial to the mass transfer and the diffusion of macromolecular reactants, having higher metal-containing capability, further concentrating active metal in the waste catalyst by the columnar structure, simultaneously exposing more surfaces by the columnar structure, increasing more active sites by further loading active components, ensuring that the catalyst has higher activity, simultaneously ensuring that the catalyst has good stability, and prolonging the operation period of the device.

(2) The polyethylene glycol solution in the invention has the following soaking treatment effects: due to the existence of the polyethylene glycol, a good skeleton supporting effect is achieved, and macroporous channels in the staggered columnar structure of the pretreated materials are well maintained when the carrier is molded. In addition, the gas generated by the decomposition of polyethylene glycol during roasting can play a role in hole expansion.

(3) The method is simple, and the alumina raw material is replaced by partial waste catalyst, so that the waste is changed into valuable, the production cost is reduced, and the environmental pollution is reduced.

Drawings

FIG. 1 is an SEM photograph of pretreated feedstock A prepared in example 1.

FIG. 2 is an SEM photograph of pretreated feedstock A prepared in comparative example 1.

Detailed Description

The technical solutions and effects of the present invention are further described below with reference to the following examples, but the present invention is not limited to the following examples. Wt% in the present invention represents a mass fraction.

The BET method: application N₂Physical adsorption-desorption characterization of the pore structures of the carriers of the examples and the comparative examples, the specific operations are as follows: adopting ASAP-2420 type N₂And the physical adsorption-desorption instrument is used for characterizing the pore structure of the sample. GetA small amount of samples are treated in vacuum at 300 ℃ for 3-4 hours, and finally the product is placed under the condition of liquid nitrogen low temperature (-200 ℃) to carry out nitrogen absorption-desorption test. Wherein the specific surface area is obtained according to a BET equation, and the distribution rate of the pore volume and the pore diameter below 30nm is obtained according to a BJH model.

Mercury pressing method: the pore diameter distribution of the carriers of the examples and the comparative examples is characterized by applying a mercury porosimeter, and the specific operation is as follows: and characterizing the distribution of sample holes by using an American microphone AutoPore9500 full-automatic mercury porosimeter. The samples were dried, weighed into an dilatometer, degassed for 30 minutes while maintaining the vacuum conditions given by the instrument, and filled with mercury. The dilatometer was then placed in the autoclave and vented. And then carrying out a voltage boosting and reducing test. The mercury contact angle is 130 degrees, and the mercury interfacial tension is 0.485N.cm^-1The distribution ratio of the pore diameter of 100nm or more is measured by mercury intrusion method.

A scanning electron microscope is used for representing the microstructure of the alumina carrier, and the specific operation is as follows: and a JSM-7500F scanning electron microscope is adopted to represent the microstructure of the carrier, the accelerating voltage is 5KV, the accelerating current is 20 muA, and the working distance is 8 mm.

The method adopts NB/SH/T0704-.

The sulfur content in the oil product is determined by adopting an SH/T0689-.

The content of carbon residue in the oil product is determined by adopting an SH/T0266-92 standard method.

And the contents of Ni and V in the oil product are determined by adopting a GB/T34099-2017 standard method.