阅读说明：本技术 一种高纯异丙醇铝的连续化制备方法 (Continuous preparation method of high-purity aluminum isopropoxide ) 是由 张志峰 周海东 余瑶辰 于 2021-01-25 设计创作，主要内容包括：本发明公开了一种高纯异丙醇铝的连续化制备方法,所述制备方法包括以下步骤：S1异丙醇铝合成：向通道反应器的一端加入一定量的金属铝和催化剂,在通道反应器的另一端则匀速通入异丙醇,在催化剂的作用下,异丙醇和金属铝进行连续反应；S2异丙醇铝提纯：反应结束后,经过连续精馏装置处理得到高纯异丙醇铝产品。本发明高纯异丙醇铝的连续化制备方法,一方面,制备得到的异丙醇铝纯度高,另外一方面可实现高纯异丙醇铝的连续化生产,其工艺简单、操作方便,满足工业化生产的需求。(The invention discloses a continuous preparation method of high-purity aluminum isopropoxide, which comprises the following steps: s1 aluminum isopropoxide synthesis: adding a certain amount of metallic aluminum and a catalyst into one end of the channel reactor, introducing isopropanol into the other end of the channel reactor at a constant speed, and continuously reacting the isopropanol with the metallic aluminum under the action of the catalyst; s2 purification of aluminum isopropoxide: and after the reaction is finished, treating the mixture by a continuous rectification device to obtain a high-purity aluminum isopropoxide product. The continuous preparation method of the high-purity aluminum isopropoxide has the advantages that on one hand, the prepared aluminum isopropoxide is high in purity, on the other hand, the continuous production of the high-purity aluminum isopropoxide can be realized, the process is simple, the operation is convenient, and the requirement of industrial production is met.)

1. A continuous preparation method of high-purity aluminum isopropoxide is characterized by comprising the following steps:

s1 aluminum isopropoxide synthesis: adding a certain amount of metallic aluminum and a catalyst into one end of the channel reactor, introducing isopropanol into the other end of the channel reactor at a constant speed, and continuously reacting the isopropanol with the metallic aluminum under the action of the catalyst;

s2 purification of aluminum isopropoxide: after the reaction is finished, the high-purity aluminum isopropoxide product is obtained at the tower bottom after the treatment of the continuous rectification device.

2. The continuous preparation method of high-purity aluminum isopropoxide according to claim 1, wherein the length-diameter ratio of the channel reactor is 20-30: 1, a plurality of micro-mixing reaction zones are arranged in the channel reactor along the length direction of the reactor.

3. The continuous production method of high-purity aluminum isopropoxide according to claim 1, wherein the purity of the high-purity aluminum isopropoxide product is more than 99.99%.

4. The continuous production method of high-purity aluminum isopropoxide according to claim 1, wherein the initiation temperature of the reaction is 40 to 50 ℃ and the reaction temperature is 80 to 90 ℃.

5. The continuous production method of high-purity aluminum isopropoxide according to claim 1, wherein the residence time of isopropanol in the channel reactor is 60-90 min.

6. The continuous production method of high-purity aluminum isopropoxide according to claim 1, wherein the metallic aluminum is aluminum block or aluminum particles.

7. The continuous production method of high-purity aluminum isopropoxide according to claim 1, wherein the catalyst is aluminum isopropoxide and/or tri-n-propylaluminum.

8. The continuous production method of high-purity aluminum isopropoxide according to claim 1, wherein the mass ratio of the metallic aluminum to the catalyst to the isopropanol is 10:0.01 to 0.05:0.5 to 3.

9. The continuous preparation method of high-purity aluminum isopropoxide according to claim 1, wherein the operating temperature of the rectifying device is 85-95 ℃ and the operating pressure is normal pressure.

10. The continuous production method of high-purity aluminum isopropoxide according to claim 1, wherein the isopropanol which does not participate in the reaction is obtained from the top of the rectifying apparatus and is recycled to the inlet of the channel reactor.

Technical Field

The invention relates to the technical field of aluminum isopropoxide synthesis, in particular to a continuous preparation method of high-purity aluminum isopropoxide.

Background

With the development of science and technology, the demand of ultrafine high-purity alumina powder is increasing at home and abroad, and higher requirements on the granularity, purity and uniformity of the high-purity alumina powder are provided. Currently, high purity alumina is typically prepared by aluminum isopropoxide: aluminum isopropoxide is hydrolyzed to obtain aluminum hydroxide, and then the aluminum hydroxide is further calcined to obtain high-purity aluminum oxide powder. Therefore, in order to obtain high purity alumina powder, it is very critical to prepare high purity aluminum isopropoxide.

The synthesis process of aluminum isopropoxide generally comprises the step of generating aluminum isopropoxide from aluminum and isopropanol under the action of a catalyst, wherein the commonly used catalyst is HgCl₂、AlCl₃、I₂In recent years, CuCl has been reported₂The catalyst was used to synthesize aluminum isopropoxide. The existing method for preparing aluminum isopropoxide is intermittent reaction, has low production efficiency, introduces additional impurities, is difficult to completely remove, influences the purity of the product and is not beneficial to industrial requirements.

In view of the above, it is desirable to provide a continuous preparation method of high-purity aluminum isopropoxide.

Disclosure of Invention

In view of the defects of the prior art, the invention mainly aims to provide a continuous preparation method of high-purity aluminum isopropoxide, so as to solve the problems of low production efficiency and low product purity of the conventional preparation method of aluminum isopropoxide, and thus, the continuous preparation method meets the requirement of industrial continuous production.

In order to achieve the above purposes, the technical scheme adopted by the invention is as follows:

a continuous preparation method of high-purity aluminum isopropoxide comprises the following steps:

s1 aluminum isopropoxide synthesis: adding a certain amount of metallic aluminum and a catalyst into one end of the channel reactor, introducing isopropanol into the other end of the channel reactor at a constant speed, and continuously reacting the isopropanol with the metallic aluminum under the action of the catalyst;

s2 purification of aluminum isopropoxide: after the reaction is finished, the high-purity aluminum isopropoxide product is obtained at the tower bottom after the treatment of the continuous rectification device.

Preferably, the length-diameter ratio of the channel reactor is 20-30: 1, a plurality of micro-mixing reaction zones are arranged in the channel reactor along the length direction of the reactor. The micro-mixing reaction zone is composed of an arc inner wall, a front baffle, a rear baffle and a channel reactor body, wherein the arc inner wall is arranged along the length direction of the channel reactor, and the front baffle and the rear baffle are inclined by 10-30 degrees along the flow direction of an isopropanol raw material of the channel reactor. The channel reactor can make isopropanol and metal aluminum contact and collide in a turbulent flow in the micro-mixing reaction zone, on one hand, the residence time of the isopropanol in the channel reactor is prolonged, so that the isopropanol and the metal aluminum react more fully, on the other hand, the contact area of a solid phase and a liquid phase is increased, and the reaction yield of the aluminum isopropoxide is further improved.

Preferably, the purity of the high purity aluminum isopropoxide product is greater than 99.99%.

Preferably, the initiation temperature of the reaction is 40-50 ℃, and the reaction temperature is 80-90 ℃.

Preferably, the residence time of the isopropanol in the channel reactor is 60-90 min.

Preferably, the metal aluminum is aluminum block or aluminum particle.

Preferably, the catalyst is aluminum isopropoxide and/or tri-n-propylaluminum.

Preferably, the mass ratio of the metal aluminum to the catalyst to the isopropanol is 10: 0.01-0.05: 0.5-3.

Preferably, the operation temperature of the rectifying device is 85-95 ℃, and the operation pressure is normal pressure.

Preferably, the top of the rectifying device obtains isopropanol which does not participate in the reaction, and the isopropanol is recycled to the inlet of the channel reactor.

Preferably, the aluminum isopropoxide obtained from the tower bottom of the rectifying device further comprises heavy metal impurity removal treatment operation.

The invention has the beneficial effects that:

the continuous preparation method of the high-purity aluminum isopropoxide can realize the continuous production of the high-purity aluminum isopropoxide by only adding the catalyst once, and not only ensures that the solid-liquid two-phase contact reaction is sufficient, but also avoids the high energy consumption and the impurity introduction caused by frequent material addition and frequent temperature rise of the intermittent reaction by carrying out the continuous reaction in the channel reactor with the unique structural design.

According to the continuous preparation method of the high-purity aluminum isopropoxide, disclosed by the invention, the high-purity aluminum isopropoxide is prepared by carrying out reaction of isopropanol and metal aluminum in the channel reactor, and after rectification and impurity removal treatment, the purity of the product is further improved, so that the aluminum isopropoxide with the purity of more than 99.99% is obtained.

In general, the continuous preparation method of the high-purity aluminum isopropoxide has the advantages of simple process, convenient operation and high purity of reaction products, and can meet the requirements of industrial production.

Drawings

FIG. 1 is a process flow diagram of the continuous preparation method of high purity aluminum isopropoxide according to the present invention;

FIG. 2 is an enlarged view of a portion of FIG. 1 at A;

the device comprises a channel reactor 1, a buffer tank 2, a diaphragm pump 3, a rectifying tower 4, impurity removal equipment 5, a stainless steel screen mesh 11, a micro-mixing reaction zone 12, a tubular condenser 41, a reboiler 42, an isopropanol inlet 101, a metal aluminum inlet 102, a reaction product outlet 103, a heat conduction oil inlet 104 and a heat conduction oil outlet 105.

Detailed Description

The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art.

Example 1

As shown in fig. 1 and fig. 2, the continuous preparation method of high purity aluminum isopropoxide of this embodiment includes the following steps:

first, 10kg of aluminum pellets having an average particle size of 5mm were injected into a micro-mixing reaction zone of a channel reactor through a metallic aluminum addition port of the channel reactor, which has a length-to-diameter ratio of 20: 1, introducing 40g of catalyst aluminum isopropoxide through a metallic aluminum addition port of the channel reactor; and then heating to 50 ℃, pumping isopropanol into the channel reactor through an isopropanol adding port at the rate of 1L per hour, reacting for 5min, heating to 85 ℃, carrying out continuous reflux reaction in a micro-mixing reaction zone in the channel reactor, and introducing the reaction product into a channel reactor for 60min, so that qualified aluminum isopropoxide and isopropanol mixed liquor appears at a reaction product outlet of the channel reactor. The temperature of the channel reactor is controlled through a circulating heat conducting oil jacket arranged on the outer wall of the channel reactor, a heat conducting oil inlet and a heat conducting oil outlet. And a stainless steel screen is also arranged on one side of the channel reactor close to the isopropanol adding port to prevent the added metallic aluminum from flowing out of the isopropanol adding port of the channel reactor.

And secondly, collecting the reaction product in a buffer tank, pumping the reaction product into a rectifying tower through a diaphragm pump for continuous distillation operation, distilling off isopropanol, wherein the distillation temperature is 90 ℃, obtaining 80-90 ℃ isopropanol light fraction at the top of the tower, condensing the isopropanol light fraction through a tubular condenser, collecting the isopropanol light fraction, obtaining 135-145 ℃ aluminum isopropoxide from the bottom of the tower, circularly operating the heavy fraction through a reboiler, and then passing through impurity removal equipment to obtain the high-purity aluminum isopropoxide.

Tests show that the yield of the aluminum isopropoxide is 96.8% (relative to aluminum), and the purity of the prepared high-purity aluminum isopropoxide is more than 99.99%, so that the quality requirement is met.

Example 2

The continuous preparation method of the high-purity aluminum isopropoxide comprises the following steps:

first, 10kg of aluminum pellets having an average particle size of 5mm were injected into the micro-mixing reaction zone of a channel reactor through the metallic aluminum addition port of the channel reactor, which had a length-to-diameter ratio of 25: 1, then 40g of catalyst (aluminum isopropoxide or tri-n-propylaluminum) is introduced through the metallic aluminum addition port of the channel reactor; and then heating to 50 ℃, pumping isopropanol into the channel reactor through an isopropanol adding port at the rate of 1L per hour, reacting for 5min, heating to 85 ℃, carrying out continuous reflux reaction in a micro-mixing reaction zone in the channel reactor, and introducing 72min later, wherein qualified aluminum isopropoxide and isopropanol mixed liquor appears at a reaction product outlet of the channel reactor. The temperature of the channel reactor is controlled through a circulating heat conducting oil jacket arranged on the outer wall of the channel reactor, a heat conducting oil inlet and a heat conducting oil outlet. And a stainless steel screen is also arranged on one side of the channel reactor close to the isopropanol adding port to prevent the added metallic aluminum from flowing out of the isopropanol adding port of the channel reactor.

And secondly, collecting the reaction product in a buffer tank, pumping the reaction product into a rectifying tower through a diaphragm pump for continuous distillation operation, distilling off isopropanol, wherein the distillation temperature is 90 ℃, obtaining 80-90 ℃ isopropanol light fraction at the top of the tower, condensing the isopropanol light fraction through a tubular condenser, collecting the isopropanol light fraction, obtaining 135-145 ℃ aluminum isopropoxide from the bottom of the tower, circularly operating the heavy fraction through a reboiler, and then passing through impurity removal equipment to obtain the high-purity aluminum isopropoxide.

Tests show that the yield of the aluminum isopropoxide is 97.5 percent (relative to aluminum), and the purity of the prepared high-purity aluminum isopropoxide is more than 99.99 percent and meets the quality requirement.

Example 3

The continuous preparation method of the high-purity aluminum isopropoxide comprises the following steps:

first, 10kg of aluminum pellets having an average particle size of 5mm were injected into a micro-mixing reaction zone of a channel reactor through a metallic aluminum addition port of the channel reactor, which has an aspect ratio of 30: 1, then 40g of catalyst (aluminum isopropoxide or tri-n-propylaluminum) is introduced through the metallic aluminum addition port of the channel reactor; and then heating to 50 ℃, pumping isopropanol into the channel reactor through an isopropanol adding port at the rate of 1L per hour, reacting for 5min, heating to 85 ℃, carrying out continuous reflux reaction in a micro-mixing reaction zone in the channel reactor, and introducing 88min later, so that qualified aluminum isopropoxide and isopropanol mixed liquor appears at a reaction product outlet of the channel reactor. The temperature of the channel reactor is controlled through a circulating heat conducting oil jacket arranged on the outer wall of the channel reactor, a heat conducting oil inlet and a heat conducting oil outlet. And a stainless steel screen is also arranged on one side of the channel reactor close to the isopropanol adding port to prevent the added metallic aluminum from flowing out of the isopropanol adding port of the channel reactor.

And secondly, collecting the reaction product in a buffer tank, pumping the reaction product into a rectifying tower through a diaphragm pump for continuous distillation operation, distilling off isopropanol at the distillation temperature of 95 ℃, obtaining 80-90 ℃ isopropanol light fraction at the top of the tower, condensing the isopropanol light fraction through a tubular condenser, collecting the isopropanol light fraction, obtaining 135-145 ℃ aluminum isopropoxide as heavy fraction at the bottom of the tower, circularly operating the heavy fraction through a reboiler, and then passing through impurity removal equipment to obtain high-purity aluminum isopropoxide.

Tests show that the yield of the aluminum isopropoxide is 98.1% (relative to aluminum), and the purity of the prepared high-purity aluminum isopropoxide is more than 99.99%, so that the quality requirement is met.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are merely illustrative of the principles of the invention, but that various changes and modifications may be made without departing from the spirit and scope of the invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.