阅读说明：本技术 氧化镁固体碱蒽醌降解物再生催化剂的制备方法和应用 (preparation method and application of magnesium oxide solid base anthraquinone degradation product regeneration catalyst ) 是由 冯拥军 李殿卿 唐平贵 冯俊婷 俞杰 李国印 胡长军 万志群 于 2019-09-19 设计创作，主要内容包括：本发明属于化工技术领域,具体涉及一种氧化镁固体碱蒽醌降解物再生催化剂的制备方法,包括下述步骤：室温下,以镁盐及其结晶水合物为镁源,多元醇作为孔隙形成和结构导向剂,弱碱为沉淀剂,将沉淀后的物体进行洗涤后烘干,制得花状氧化镁前驱体；再将所述前驱体在空气中煅烧得到所述多孔花状氧化镁蒽醌降解物再生催化剂。本发明主要解决蒽醌降解物再生催化剂活性不足且稳定性低的问题,从而确保其再生催化活性的高效性和持久性。(The invention belongs to the technical field of chemical industry, and particularly relates to a preparation method of a magnesium oxide solid alkali anthraquinone degradation product regenerated catalyst, which comprises the following steps: at room temperature, taking magnesium salt and crystal hydrate thereof as a magnesium source, taking polyalcohol as a pore forming and structure directing agent and taking weak base as a precipitating agent, washing and drying the precipitated object to prepare a flower-shaped magnesium oxide precursor; and calcining the precursor in the air to obtain the porous flower-like magnesium oxide anthraquinone degradation product regenerated catalyst. The invention mainly solves the problems of insufficient activity and low stability of the anthraquinone degradation product regenerated catalyst, thereby ensuring the high efficiency and the durability of the regenerated catalytic activity.)

1. The preparation method of the magnesium oxide solid alkali anthraquinone degradation product regeneration catalyst is characterized by comprising the following steps of: at room temperature, taking magnesium salt and crystal hydrate thereof as a magnesium source, taking polyalcohol as a pore forming and structure directing agent and taking weak base as a precipitating agent, washing and drying the precipitated object to prepare a flower-shaped magnesium oxide precursor; and calcining the precursor in the air to obtain the porous flower-like magnesium oxide anthraquinone degradation product regenerated catalyst.

2. The method of claim 1, wherein:

The magnesium salt is MgSO₄、MgCl₂Or Mg (NO)₃)₂。

3. The method of claim 1, wherein:

the weak base is ammonia water, urea or urotropine.

4. The method of claim 1, wherein:

the polyalcohol is ethylene glycol or glycerol.

5. The method of claim 1, wherein:

The polyol and Mg²⁺The molar ratio is 0-30.

6. A porous flower-like magnesium oxide anthraquinone degradation product regeneration catalyst is characterized in that:

prepared by the method of any one of claims 1 to 5.

7. The porous flower-like magnesia anthraquinone degradation product regeneration catalyst according to claim 6, characterized in that: the specific surface area of the porous flower-shaped magnesia anthraquinone degradation product regenerated catalyst is 53-120 m²g^-1the porosity is 55-83%.

8. The porous flower-like magnesia anthraquinone degradation product regeneration catalyst according to claim 6 or 7, which is used as an anthraquinone degradation product regeneration catalyst in the industry of preparing hydrogen peroxide by an anthraquinone method.

Technical Field

the invention relates to a preparation method and application of a magnesium oxide solid alkali anthraquinone degradation product regenerated catalyst.

background

Hydrogen peroxide (H)₂O₂) Is an environment-friendly basic fine chemical and is widely applied to the fields of medicine, chemical synthesis, environmental protection, paper making, textile and the like. The global annual consumption of the hydrogen peroxide exceeds 2000 million tons (calculated according to the mass concentration of 27.5 percent), the annual output of China reaches 1250 million tons, and the hydrogen peroxide is the largest producing country and consuming country in the world. The anthraquinone process is the only international process for producing hydrogen peroxide, and anthraquinone derivatives which do not have hydrogen peroxide production capacity and are difficult to avoid in the hydrogenation or oxidation of anthraquinone are called anthraquinone degradants. Most of the anthraquinone degradation products can be converted into effective anthraquinones by the action of the regenerated catalyst and reused, and the regeneration efficiency depends on the performance of the regenerated catalyst. At present, the degradation problem of active anthraquinone troubles hydrogen peroxide production enterprises and is one of the main factors influencing the technical progress of the whole industry for preparing hydrogen peroxide by an anthraquinone method.

At present, anthraquinone degradation product regeneration catalysts in the market are mainly active alumina carriers loaded with NaOH, KOH or corresponding oxides and other active components, but the active components are easy to dissolve in water and run off in the using process, and the average service life is less than 60 days. The short service life of the catalyst means that the catalyst needs to be continuously updated, the production cost of the hydrogen peroxide is increased, the environment is polluted, and the precious aluminum resource of the country is wasted, so that how to prepare the anthraquinone degradation product regenerated catalyst with high activity and long service life is always a hot point concerned by the hydrogen peroxide industry and a key problem which needs to be broken through urgently.

US0018013 discloses a regenerated catalyst of anthraquinone degradation products in the preparation of hydrogen peroxide by an anthraquinone process and a preparation method thereof, soluble magnesium salts are loaded into alumina pore channels by adopting an impregnation mode, and the catalyst is roasted at a proper temperature to prepare 1-50 wt% of MgO/gamma-Al₂O₃. In MgO/gamma-Al₂O₃in the composite system, because magnesium oxide is easily converted into magnesium hydroxide crystals in a water-containing system, alumina pore channels are cracked, the service life of the regenerated catalyst is shortened, and the crushed particles easily block the regenerated system to influence the normal operation of the whole system. However, the regeneration activity was improved, indicating that magnesium oxide has regeneration catalytic activity.

Chinese patent CN105174229 discloses a composite anthraquinone process hydrogen peroxide working solution active regenerant and a preparation method thereof, mainly a two-layer or three-layer composite coating structure is designed and constructed, and the problems of excessively strong alkalinity, uncontrollable temperature and instability of the working solution are solved.

Magnesium oxide is a typical solid base catalyst with low cost, has better regeneration activity on anthraquinone degradation products, and the high specific surface area and the proper pore size and distribution of the magnesium oxide undoubtedly facilitate the improvement of the regeneration activity of the magnesium oxide. Most of the porous structure magnesium oxide is prepared in a pressure-resistant reactor under a template-assisted high-temperature high-pressure hydrothermal route, and the template removal post-treatment is complex (Zhang z., Zheng y., Chen j., Zhang q., Ni y., Liang x., adv.funct.mater.,2007,17, (14), 2447-2454.). These methods are of course unsuitable for large-scale production and use. Therefore, people pay more attention to exploring a method for efficiently and controllably preparing a flower-shaped magnesium oxide microsphere anthraquinone degradation product regenerated catalyst with a hierarchical pore structure.

The invention mainly solves the problems of insufficient activity and low stability of the anthraquinone degradation product regenerated catalyst, thereby ensuring the high efficiency and the durability of the regenerated catalytic activity. Therefore, the invention promotes the technical upgrade of the whole industry for preparing the hydrogen peroxide by the anthraquinone process, promotes the market competitiveness of hydrogen peroxide products in China, and promotes the high-value, efficient, green and sustainable utilization of the national strategic aluminum resource.

Disclosure of Invention

the invention aims to provide a preparation method and application of a magnesium oxide solid alkali anthraquinone degradation product regenerated catalyst, which ensure the high efficiency and the durability of the regenerated catalytic activity, promote the technical upgrade of the whole anthraquinone method hydrogen peroxide industry, and are beneficial to the high-value, high-efficiency, green and sustainable utilization of aluminum resources.

In order to solve the technical problems, the invention provides a preparation method of a magnesium oxide solid alkali anthraquinone degradation product regeneration catalyst, which is characterized by comprising the following steps: at room temperature, taking magnesium salt and crystalline hydrate thereof as a magnesium source, taking weak base as a precipitator and taking polyalcohol as a pore forming and structure directing agent, and preparing a flower-like magnesium oxide precursor by adopting one-step precipitation reaction; and calcining the precursor in the air to obtain the porous flower-like magnesium oxide anthraquinone degradation product regenerated catalyst.

Wherein the magnesium salt is MgSO₄、MgCl₂Or Mg (NO)₃)₂。

Wherein the weak base is ammonia water, urea or urotropine.

Wherein the polyalcohol is glycol or glycerol.

Wherein the polyol is reacted with Mg²⁺The molar ratio is 0-30.

a porous flower-shaped regenerated catalyst for the degradation products of anthraquinone in magnesia is prepared from the raw materials of anthraquinone and solid alkali.

Wherein the specific surface area of the porous flower-like magnesium oxide anthraquinone degradation product regenerated catalyst is 53-120 m²g^-1The porosity is 55-83%.

a porous flower-shaped regenerated catalyst of anthraquinone degradation products of magnesia is used as a regenerated catalyst of anthraquinone degradation products in the industry of preparing hydrogen peroxide by an anthraquinone method.

the invention has the beneficial effects that:

1. The reaction raw materials are cheap and easy to obtain;

2. The reaction is mild, and the dispersion effect of the structure-directing agent on the magnesium oxide is skillfully utilized, so that the formation of pores is effectively controlled, the growth of crystal grains is promoted, the agglomeration of particles is prevented, and the reaction can be smoothly finished at normal temperature and normal pressure;

3. The environmental protection of the reaction, the synthetic method does not involve any link and product which pollute the environment, is a green and cheap synthetic method, and has great practical significance in industrial application.

4. The practicability of the material is that the porosity of the porous flower-like magnesium oxide anthraquinone degradation product regenerated catalyst prepared by the method can reach 83.20% at most, and the specific surface area reaches 53-120 m²g^-1The catalyst is used for regenerating anthraquinone degradation products in the industry of preparing hydrogen peroxide by an anthraquinone process, and has an obvious effect, wherein the regeneration effect is 5-8g/L, and the regeneration capacity of the catalyst is obviously higher than that of the currently used regenerated catalysts such as activated alumina.

Drawings

FIG. 1 is an XRD spectrum of MgO samples prepared in examples 1, 2 and 3.

FIG. 2 is an SEM photograph of MgO samples prepared in examples 1, 2 and 3, wherein (A), (B) and (C) correspond to example 1; (D) examples 2, E and F; (G) the symbols (A), (B), (C), (D), (E), (D), (.

FIG. 3 is a graph showing pore structure analysis of MgO prepared in examples 1, 2 and 3, wherein A is a graph showing low-temperature nitrogen adsorption and desorption curves of examples 1, 2 and 3; b is an aperture distribution diagram obtained by low-temperature nitrogen adsorption and desorption calculation; c is a porosity chart measured by a mercury intrusion method; d is the overall aperture profile.

Detailed Description

The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic views illustrating only the basic structure of the present invention in a schematic manner, and thus show only the constitution related to the present invention.