阅读说明：本技术 一种棉花类纤维素制取富含乙醇酸甲酯液体的方法 (Method for preparing liquid rich in methyl glycolate from cotton cellulose ) 是由 彭锦星 刘新媛 鲍振博 于 2020-12-03 设计创作，主要内容包括：本发明涉及一种棉花类纤维素的制备富含乙醇酸甲酯液体的方法,其特征在于,步骤为：步骤1、首先对棉花类纤维素原料进行干燥处理,使原料的含水率小于10％；步骤2、然后将甲醇和棉花类纤维素原料送入密封耐压装置中进行升温升压,其温度控制在260℃～310℃,压力在6MPa～20MPa,并在此状态保持0.5～9小时；步骤3、冷却后进行过滤、固液分离,得到的液体为富含乙醇酸甲酯的液体。本发明利用超临界甲醇,将棉花纤维素转化为富含乙醇酸甲酯液体,富含乙醇酸甲酯液体可进一步提取制备乙醇酸甲酯。(The invention relates to a method for preparing liquid rich in methyl glycolate from cotton cellulose, which is characterized by comprising the following steps: step 1, firstly, drying a cotton cellulose raw material to enable the water content of the raw material to be less than 10%; step 2, feeding the methanol and the cotton cellulose raw materials into a sealed pressure-resistant device for heating and boosting, controlling the temperature to be 260-310 ℃ and the pressure to be 6-20 MPa, and keeping the state for 0.5-9 hours; and 3, cooling, filtering, and carrying out solid-liquid separation to obtain liquid rich in methyl glycolate. The invention utilizes supercritical methanol to convert cotton cellulose into liquid rich in methyl glycolate, and the liquid rich in methyl glycolate can be further extracted to prepare methyl glycolate.)

1. A method for preparing liquid rich in methyl glycolate from cotton cellulose is characterized by comprising the following steps:

step 1, firstly, drying a cotton cellulose raw material to enable the water content of the raw material to be less than 10%;

step 2, feeding the methanol and the cotton cellulose raw materials into a sealed pressure-resistant device for heating and boosting, controlling the temperature to be 260-310 ℃ and the pressure to be 6-20 MPa, and keeping the state for 0.5-9 hours;

and 3, cooling, filtering, and carrying out solid-liquid separation to obtain liquid rich in methyl glycolate.

2. The method of preparing methyl glycolate rich liquid of claim 1, wherein:

in the step 1, the cotton cellulose is one or a mixture of cotton, absorbent cotton and cellulose substances.

3. The method of preparing methyl glycolate rich liquid of claim 1, wherein:

in the step 2, the purity of the adopted methanol is 90-100 v/v%; the amount of methanol used was: 1-20 ml of the raw material is used for every 1 g of cotton cellulose.

4. The method of preparing methyl glycolate rich liquid of claim 1, wherein: the alcoholysis rate of the liquid obtained in the step 3 is 30-80%, and the content of methyl glycolate is 10-40%.

5. The method of preparing methyl glycolate rich liquid of claim 1, wherein: and (3) adding a certain amount of catalyst in the step (2), wherein the catalyst adopts potassium carbonate or sodium carbonate.

Technical Field

The invention belongs to the technical field of new materials and the technical field of resource utilization of solid wastes, and particularly relates to a method for preparing a liquid rich in methyl glycolate from cotton cellulose.

Background

Cotton is one of the most important crops worldwide. Cotton is also a raw material for textile and fine chemical industry and an important strategic material. The annual cotton yield of China in 2019 is 588.9 ten thousand tons. The cotton fiber is a raw material of fabrics with various specifications, and is mainly used as a raw material of various clothes, furniture cloth and industrial cloth.

Methyl glycolate is an important chemical raw material and has the chemical properties of both alcohol and ester. The main application fields of methyl glycolate are chemical industry, dye, medicine field and the like. The methyl glycolate can be used for preparing high-added-value chemical raw materials such as glycine, glycolic acid, dimethyl malonate and the like. Therefore, the development and research value of methyl glycolate is higher and higher.

Therefore, the preparation of methyl glycolate by using cotton cellulose has important research and practical value.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a method for preparing a liquid rich in methyl glycolate from cotton cellulose.

A method for preparing liquid rich in methyl glycolate from cotton cellulose is characterized by comprising the following steps:

step 1, firstly, drying a cotton cellulose raw material to enable the water content of the raw material to be less than 10%;

step 2, feeding the methanol and the cotton cellulose raw materials into a sealed pressure-resistant device for heating and boosting, controlling the temperature to be 260-310 ℃ and the pressure to be 6-20 MPa, and keeping the state for 0.5-9 hours;

and 3, cooling, filtering, and carrying out solid-liquid separation to obtain liquid rich in methyl glycolate.

Further: in the step 1, the cotton cellulose is one or a mixture of cotton, absorbent cotton and cellulose substances.

Further: in the step 2, the purity of the adopted methanol is 90-100 v/v%; the amount of methanol used was: 1-20 ml of the raw material is used for every 1 g of cotton cellulose.

Further: the alcoholysis rate of the liquid obtained in the step 3 is 30-80%, and the content of methyl glycolate is 10-40%.

Further: and (3) adding a certain amount of catalyst in the step (2), wherein the catalyst adopts potassium carbonate or sodium carbonate.

The invention has the advantages and positive effects that:

1. the invention utilizes supercritical methanol to convert cotton cellulose into liquid rich in methyl glycolate, and the liquid rich in methyl glycolate can be further extracted to prepare methyl glycolate.

2. The invention selects methanol reaching a supercritical state as a reaction medium, and has lower critical temperature and critical pressure. Methanol has the advantage of being non-toxic relative to other alcohols.

2. The method has the advantages of mild conditions and low requirements on reaction equipment.

Detailed Description

In order to further understand the contents, features and effects of the present invention, the following examples are given and detailed below. It should be noted that the present embodiment is illustrative, not restrictive, and the scope of the invention should not be limited thereby.

The invention discloses a method for preparing liquid rich in methyl glycolate from cotton cellulose, which comprises the following steps: the method comprises the following steps:

step 1, drying the cotton cellulose raw material to ensure that the water content of the raw material is less than 10%, wherein the cotton cellulose raw material can adopt one or a mixture of more of cotton, absorbent cotton and cellulose substances.

Step 2, feeding the methanol and the cotton cellulose raw material into a sealed pressure-resistant device, and adding a certain amount of a catalytic frame, such as potassium carbonate or sodium carbonate, heating and boosting the pressure under an anoxic state, wherein the temperature is controlled to be 260-310 ℃, the pressure is controlled to be 6-20 MPa, and the state is kept for 0.5-9 hours, wherein the purity of the adopted methanol is 90-100 v/v%; the amount of methanol used was: 1-20 ml of the raw material is used for every 1 g of cotton cellulose. Under the temperature and pressure environment, the methanol reaches a supercritical state, so that the methanol has excellent transfer characteristics, dissolution characteristics and reaction characteristics. Compared with supercritical water, the method has the advantages of milder operation condition and lower boiling point, and is more beneficial to further separation of products.

And 3, cooling, filtering, and carrying out solid-liquid separation to obtain liquid rich in methyl glycolate. Wherein, the alcoholysis rate is 30-80 percent, and the content of methyl glycolate is 10-40 percent.

The method for preparing the liquid rich in methyl glycolate by using the cotton cellulose is specifically illustrated by the following two examples:

example 1:

20g of dried absorbent cotton and 300ml of 96% methanol were charged into an autoclave, the autoclave was sealed, the temperature was raised to 280 ℃ and the pressure was raised to 13.5MPa, the state was maintained for 5 hours, the mixture was cooled, and then filtered and subjected to solid-liquid separation to obtain a liquid rich in methyl glycolate, the alcoholysis rate was measured to be 65% and the content of methyl glycolate was measured to be 13%.

Example 2:

adding 20g of dried absorbent cotton and 300ml of 96% methanol into an autoclave, sealing, heating to 290 ℃, boosting to 14.5MPa, keeping the state for 5 hours, cooling, filtering, performing solid-liquid separation, wherein the alcoholysis rate is 82%, and obtaining a liquid rich in methyl glycolate, and the alcoholysis rate is 82% and the content of methyl glycolate is 20% by measurement.

It will be understood that modifications and variations can be made by persons skilled in the art in light of the above teachings and all such modifications and variations are intended to be included within the scope of the invention as defined in the appended claims.