CN112694867A

CN112694867A - Method for preparing adhesive by water-settling acidified tetrahydrofurfuryl alcohol-treated biomass

Info

Publication number: CN112694867A
Application number: CN202011531615.9A
Authority: CN
Inventors: 徐建; 左宗涛; 王超; 顾帅令; 吴海军; 阮宏清; 尚兵; 张楷; 徐霞
Original assignee: Anhui University of Technology AHUT
Current assignee: Anhui University of Technology AHUT
Priority date: 2020-12-22
Filing date: 2020-12-22
Publication date: 2021-04-23

Abstract

The invention discloses a method for preparing an adhesive by biomass treated by water-settling acidified tetrahydrofurfuryl alcohol, which belongs to the technical field of lignin extraction in biomass and material chemical adhesives, and comprises the following steps: (1) crushing, sieving, washing and drying the raw materials to obtain raw material powder; (2) adding 5g of raw material powder into 20-100ml of tetrahydrofurfuryl alcohol, adding 72 wt% of sulfuric acid into the tetrahydrofurfuryl alcohol, and obtaining a pretreatment material after the reaction is finished; (3) rapidly cooling the pretreatment material to room temperature by using cold water, adding the pretreatment material into distilled water for precipitation, and separating a solid phase and a liquid phase after the precipitation is finished to obtain a jelly; (4) drying the jelly in vacuum to obtain a target product; the invention has simple preparation process, short preparation time and low energy consumption, and can prepare excellent adhesive.

Description

Method for preparing adhesive by water-settling acidified tetrahydrofurfuryl alcohol-treated biomass

Technical Field

The invention relates to the technical field of lignin extraction and material chemical adhesives in biomass, in particular to a method for preparing an adhesive from biomass treated by water-settling acidification tetrahydrofurfuryl alcohol.

Background

In recent years, the growing problem of wood shortage in China has attracted the attention of experts who are trying to develop various methods for effectively utilizing wood resources. Urea Formaldehyde (UF), Phenol Formaldehyde (PF) and Melamine Formaldehyde (MF) resins are the most widely used wood adhesives in the medium density fiberboard industry, but they pose a hazard to both the environment and human health due to the release of free formaldehyde. In order to overcome the disadvantages of formaldehyde-containing adhesives, experts are trying to find wood adhesives that are low or non-toxic by reducing the molar ratio and adding formaldehyde scavengers during the preparation process. In addition, petroleum resources for the production of UF, PF and MF resins are rapidly being exhausted. Therefore, it is important to develop formaldehyde-free binders from non-petroleum resources.

Although phenolic aldehyde (PF) resins have a long history since their first invention in 1907, they are still in the indispensable position in composite substrates, adhesives, flame retardant materials and the like, but there is an increasing interest in environmental friendliness, rising price of phenol and the desire to reduce dependence on crude oil, which has prompted the increase of the use of green alternatives in chemical and material production. In addition, the world health organization's international agency classifies formaldehyde as a carcinogen with genetic toxicity. Phenol and its vapors are also harmful to the human eye, skin and respiratory tract, as well as the central nervous system and heart. Further, the price of phenol has increased significantly in recent years due to the rising price of crude oil. Thus, adhesives synthesized with renewable substitutes are of great interest.

At present, the raw materials in the traditional adhesive production process cannot be regenerated and toxic, the environmental pollution is large in the production process, and the operation is complicated.

Therefore, a method for preparing an adhesive by water-precipitating and acidifying tetrahydrofurfuryl alcohol-treated biomass is proposed to solve the above problems.

Disclosure of Invention

The invention aims to utilize sustainable green energy biomass, adopt a simple process to replace phenol and formaldehyde in the traditional phenolic resin and synthesize an adhesive.

In order to achieve the purpose, the invention provides the following scheme to realize the following steps:

the invention provides a method for preparing an adhesive by using biomass treated by water-settling acidified tetrahydrofurfuryl alcohol, which specifically comprises the following steps:

(1) crushing, sieving, washing and drying the raw materials to obtain raw material powder;

(2) adding 5g of raw material powder into 20-100ml of tetrahydrofurfuryl alcohol, adding 72 wt% of sulfuric acid into the tetrahydrofurfuryl alcohol, and obtaining a pretreatment material after the reaction is finished;

(3) rapidly cooling the pretreatment material to room temperature by using cold water, then adding the pretreatment material into distilled water for sedimentation, and separating a solid phase and a liquid phase after the sedimentation is finished to obtain a jelly;

(4) and drying the jelly in vacuum to obtain the target product.

Preferably, in the step (1), the raw material is any one of walnut shells, poplar and pine.

Preferably, in the step (2), the reaction temperature is 140-.

Preferably, in the step (2), the addition amount of the sulfuric acid is 50-350 mM/L.

Preferably, in the step (3), the volume ratio of the distilled water to the pretreatment material is 3: 1.

Preferably, in the step (3), the settling time is 0.5-2 h.

Preferably, in the step (4), the drying temperature is 105 ℃ and the drying time is 0.5 h.

The invention has the beneficial effects that:

1. the tetrahydrofurfuryl alcohol is stable and cheap, the operation process is safe, and the environmental pollution is less;

2. the addition process is simple, the preparation time is short, and the energy consumption is low;

3. the raw materials are biomass raw materials, have wide sources and are raw materials derived from renewable resources, so that the adhesive can be continuously produced.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a process flow diagram of the present invention;

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

A method for preparing an adhesive by water-settling acidified biomass treated by tetrahydrofurfuryl alcohol specifically comprises the following steps: crushing, sieving, washing and drying walnut shells to obtain walnut shell powder; adding 5g of walnut shell powder into 50ml of tetrahydrofurfuryl alcohol, adding 72 wt% of sulfuric acid into the tetrahydrofurfuryl alcohol, and reacting at 140 ℃ for 2 hours to obtain a pretreated material, wherein the addition amount of the sulfuric acid is 50 mM/L; rapidly cooling the pretreatment material to room temperature by using cold water, then adding the pretreatment material into distilled water with the volume 3 times that of the pretreatment material, settling for 30min, and separating a solid phase from a liquid phase after the settling is finished to obtain a jelly; drying the jelly at 105 deg.C for 30min to obtain the target product.

Example 2

A method for preparing an adhesive by water-settling acidified biomass treated by tetrahydrofurfuryl alcohol specifically comprises the following steps: pulverizing pine, sieving, washing with water, and oven drying to obtain pine powder; adding 5g of pine wood powder into 25ml of tetrahydrofurfuryl alcohol, adding 72 wt% of sulfuric acid into the tetrahydrofurfuryl alcohol, and reacting for 2h at 180 ℃ to obtain a pretreatment material, wherein the addition amount of the sulfuric acid is 100 mM/L; rapidly cooling the pretreatment material to room temperature by using cold water, then adding the pretreatment material into distilled water with the volume 3 times that of the pretreatment material, settling for 30min, and separating a solid phase from a liquid phase after the settling is finished to obtain a jelly; drying the jelly at 105 deg.C for 30min to obtain the target product.

Example 3

A method for preparing an adhesive by water-settling acidified biomass treated by tetrahydrofurfuryl alcohol specifically comprises the following steps: pulverizing poplar, sieving, washing and drying to obtain poplar powder; adding 5g of poplar powder into 25ml of tetrahydrofurfuryl alcohol, adding 72 wt% of sulfuric acid into the tetrahydrofurfuryl alcohol, wherein the addition amount of the sulfuric acid is 250mM/L, and reacting for 2h at 200 ℃ to obtain a pretreatment material; rapidly cooling the pretreatment material to room temperature by using cold water, then adding the pretreatment material into distilled water with the volume 3 times that of the pretreatment material, settling for 30min, and separating a solid phase from a liquid phase after the settling is finished to obtain a jelly; drying the jelly at 105 deg.C for 30min to obtain the target product.

Result detection

1. The test method comprises the following steps: the adhesives of examples 1 to 3 were tested for bond strength. Specific detection results are shown in table 1.

TABLE 1 bonding Strength

Group of	Bonding strength/MPa
		Example 1	0.89
Example 2	1.04
		Example 3	0.83

In the description herein, references to the description of "one embodiment," "an example," "a specific example" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The preferred embodiments of the invention disclosed above are intended to be illustrative only. The preferred embodiments are not exhaustive. Obviously, many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and the practical application, to thereby enable others skilled in the art to best utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A method for preparing an adhesive by water-precipitating and acidifying biomass treated by tetrahydrofurfuryl alcohol is characterized by comprising the following steps:

(4) and drying the jelly in vacuum to obtain the target product.

2. The method for preparing the adhesive by the water-precipitation acidification of the tetrahydrofurfuryl alcohol-treated biomass according to claim 1, wherein in step (1), the raw material is any one of walnut shell, poplar and pine.

3. The method for preparing the adhesive by the water-precipitation acidification of the tetrahydrofurfuryl alcohol-treated biomass as claimed in claim 1, wherein the reaction temperature in step (2) is 140-200 ℃ and the reaction time is 1-3 h.

4. The method for preparing adhesive by water-precipitating and acidifying biomass treated with tetrahydrofurfuryl alcohol according to claim 1, wherein the amount of sulfuric acid added in step (2) is 50-350 mM/L.

5. The method for preparing adhesive by water-precipitating and acidifying biomass of tetrahydrofurfuryl alcohol according to claim 1, wherein in step (3), the volume ratio of the distilled water to the pretreatment material is 3: 1.

6. The method for preparing adhesive by water-precipitating acid-treated biomass of tetrahydrofurfuryl alcohol according to claim 1, wherein in step (3), the precipitation time is 0.5-2 h.

7. The method for preparing adhesive by water-precipitating and acidifying biomass of tetrahydrofurfuryl alcohol according to claim 1, wherein in step (4), the drying temperature is 105 ℃ and the drying time is 0.5 h.