阅读说明：本技术 生物活性炭及其制备方法 (Biological activated carbon and preparation method thereof ) 是由 李海朝 张净净 石成龙 张丽娟 祝永强 王广乐 于 2019-11-27 设计创作，主要内容包括：一种生物活性炭及其制备方法,涉及吸附材料领域。生物活性炭的制备方法包括：将原料浸渍于活化剂的水溶液中5-12h,在空气气氛中,将浸渍后的原料在300-700℃保温活化至少30min。其中,原料包括羽毛和毛发中的至少一种,活化剂选自磷酸、氢氧化钾或氯化锌。该制备方法在制备过程无需惰性气体保护、工艺简单,易于生产,同时以羽毛或毛发为原料,经活化剂改性后活化,制备出比表面积大,吸附性能高的生物活性炭；不仅有利于实现羽毛或毛发的资源化利用,而且有利于节约木材、煤炭等资源,节省制作成本,具有较佳的商业价值。(A biological activated carbon and a preparation method thereof relate to the field of adsorption materials. The preparation method of the biological activated carbon comprises the following steps: soaking the raw material in the aqueous solution of an activating agent for 5-12h, and in an air atmosphere, preserving the heat of the soaked raw material at the temperature of 300-700 ℃ for activation for at least 30 min. Wherein the raw material comprises at least one of feather and hair, and the activating agent is selected from phosphoric acid, potassium hydroxide or zinc chloride. The preparation method does not need inert gas protection in the preparation process, has simple process and easy production, and takes the feathers or the hair as the raw material, and the feather or the hair is activated after being modified by the activating agent to prepare the biological activated carbon with large specific surface area and high adsorption performance; the feather and hair recycling agent is beneficial to realizing the resource utilization of feathers or hairs, saving resources such as wood, coal and the like, saving the manufacturing cost and having better commercial value.)

1. A preparation method of biological activated carbon is characterized by comprising the following steps:

soaking the raw materials in an aqueous solution of an activating agent for 5-12 h;

in the air atmosphere, the impregnated raw materials are subjected to heat preservation and activation at the temperature of 300-700 ℃ for at least 30 min;

wherein the raw material comprises at least one of feathers and hair;

the activating agent is selected from phosphoric acid, potassium hydroxide or zinc chloride.

2. The preparation method according to claim 1, wherein the mass ratio of the aqueous solution of the activating agent to the raw material is 1 (1-5).

3. The production method according to claim 1, wherein the aqueous solution of the activator is a phosphoric acid solution having a mass concentration of 50 to 85%;

optionally, when the raw material is feather and the activating agent is phosphoric acid, the impregnated raw material is subjected to heat preservation and activation at the temperature of 300-600 ℃;

optionally, when the raw material is hair and the activating agent is phosphoric acid, the impregnated raw material is activated at the temperature of 300-500 ℃.

4. The production method according to claim 1, wherein the aqueous solution of the activator is a potassium hydroxide solution having a mass concentration of not less than 30%;

optionally, when the raw material is feather and the activating agent is potassium hydroxide, the impregnated raw material is subjected to heat preservation and activation at the temperature of 500-700 ℃;

optionally, when the raw material is hair and the activating agent is potassium hydroxide, the impregnated raw material is activated at 400-700 ℃ under heat preservation.

5. The production method according to claim 1, wherein the aqueous solution of the activator is a zinc chloride solution having a mass concentration of not less than 40%.

6. The method according to claim 5, wherein when the raw material is feather and the activating agent is zinc chloride, the impregnated raw material is activated at 600 ℃ at 300-;

optionally, when the raw material is hair and the activating agent is zinc chloride, the impregnated raw material is activated at 300-500 ℃.

7. The method of any one of claims 1 to 6, wherein the step of activating comprises:

and (3) placing the impregnated raw materials in a muffle furnace, heating to an activation temperature at a speed of 19-21 ℃/min, and carrying out heat preservation and activation for 30-90 min.

8. The method according to any one of claims 1 to 6, further comprising, after the activation, washing the obtained product with water to the same pH as the water, drying, and grinding.

9. The method according to any one of claims 1 to 6, further comprising washing and drying the raw material before immersing the raw material in the aqueous solution of the activating agent.

10. A bio-activated carbon, characterized in that it is produced by the production method according to any one of claims 1 to 9.

Technical Field

The application relates to the field of adsorption materials, in particular to biological activated carbon and a preparation method thereof.

Background

The carbon adsorption material is a porous carbon-containing material, has the characteristics of developed pore structure, large specific surface area and the like, is an excellent adsorbent, has stable performance, is easy to regenerate, is an environment-friendly adsorbent, and is widely applied to the directions of metallurgy, chemical industry, environmental protection and the like. At present, in the preparation process of the carbon adsorption material, substances with rich carbon-containing elements, such as wood, coal, various nut shells and the like, are mainly used as raw materials, and it is necessary to develop and utilize renewable resources to prepare the activated carbon.

Disclosure of Invention

The present application provides a biological activated carbon and a preparation method thereof to improve the above technical problems.

A method of making a biological activated carbon according to an embodiment of the first aspect of the application, comprising:

soaking the raw materials in the aqueous solution of the activating agent for 5-12 h.

In the air atmosphere, the impregnated raw materials are subjected to heat preservation and activation at the temperature of 300-700 ℃ for at least 30 min.

Wherein the raw material comprises at least one of feather and hair.

The activator is selected from phosphoric acid, potassium hydroxide or zinc chloride.

According to the preparation method of the biological activated carbon, the feather or the hair is used as the raw material, so that the resource utilization of waste is realized, the environment pollution is prevented, the resources such as wood, coal and the like are saved, meanwhile, the activation is performed by adopting the activating agent for modification under the air atmosphere, the activation is not required to be performed under the protection of inert gas, and finally, the raw material is changed into the biological activated carbon with large specific surface area and high methylene blue adsorption value.

The biological activated carbon according to the second aspect embodiment of the application is prepared by the preparation method of the biological activated carbon provided by the first aspect embodiment of the application.

The biological activated carbon prepared by the method has large specific surface area and high methylene blue adsorption value.

The biological activated carbon provided by the embodiment of the application and the preparation method and application thereof have the beneficial effects that:

1. the invention uses waste: feather and/or hair are used as raw materials, and are activated after being modified by an activating agent to prepare the biological activated carbon with large specific surface area and high adsorption performance; is beneficial to realizing the resource utilization of the feather or the hair and saving resources such as wood, coal and the like.

2. The prepared biological activated carbon can be used for replacing part of the traditional activated carbon products; and the biological activated carbon does not need inert gas protection in the preparation process, and the process is simple and easy to produce.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The following is a detailed description of the bio-activated carbon and the method of preparing the same according to the examples of the present application.

A biological activated carbon is prepared by the following preparation method:

s1, soaking the raw materials in an aqueous solution of an activating agent for 5-12 h.

The raw materials are soaked in the aqueous solution of the activating agent for 5-12h, such as 5h, 7h, 8h, 9h, 10h, 11h or 12h, and the surface of the raw materials is modified by the activating agent through a soaking arrangement, so that the finally obtained biological activated carbon has a larger specific surface area and a higher methylene blue adsorption value. Wherein the impregnation is carried out at normal temperature, for example 20-35 ℃.

Wherein the raw material comprises at least one of feather and hair, for example, the raw material is feather, or hair, or a mixture of feather and hair.

The hair includes animal hair (such as wool, dog hair, etc.) and human hair, and both are basically the same and are composed of hair shaft and hair root. The feather or hair is used as the raw material to prepare the biological activated carbon, so that the price of the raw material can be reduced, the pollution of the feather or hair as waste to the environment is prevented, and the compression of human to the environment can be relieved.

Optionally, in order to ensure the sufficiency of the activation of the raw material and prevent the introduction of impurities during the subsequent activation, the method for preparing biochar further includes washing and drying the raw material before the step S1 (dipping the raw material in the aqueous solution of the activating agent).

Wherein the activating agent is selected from phosphoric acid, potassium hydroxide or zinc chloride, and the activating agent can effectively modify the raw materials.

Alternatively, the aqueous solution of the activator is a phosphoric acid solution having a mass concentration of 50-85%, for example, the aqueous solution of the activator is a phosphoric acid solution having a mass concentration of any one of 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85% or a range between any two of the above. The phosphoric acid solution within the above-mentioned mass concentration range is excellent in the modification effect.

Alternatively, the aqueous solution of the activator is a potassium hydroxide solution having a mass concentration of not less than 30%, for example, the aqueous solution of the activator is a potassium hydroxide solution having a mass concentration of any one of 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, etc., or a value in a range between any two of them. The potassium hydroxide solution in the above mass concentration range has a good modification effect. It should be noted that the mass concentration of the aqueous solution of the activator cannot exceed 100% and cannot exceed the concentration of its saturated solution.

Optionally, the aqueous solution of the activator is a zinc chloride solution with a mass concentration of not less than 40%. For example, the aqueous solution of the activator is a zinc chloride solution having a mass concentration of any one of 41%, 45%, 50%, 55%, 60%, 65%, 70%, etc., or a value in a range between any two of these values. The zinc chloride solution within the mass concentration range has good modification effect. It should be noted that the mass concentration of the aqueous solution of the activator cannot exceed 100% and cannot exceed the concentration of its saturated solution.

S2, in the air atmosphere, the impregnated raw materials are subjected to heat preservation and activation for at least 30min at the temperature of 300-700 ℃.

The method adopts air atmosphere activation at the activation temperature of 300-700 ℃, does not need to be carried out under the protection condition of inert gas such as nitrogen, has simple preparation method, and simultaneously has large specific surface area and high methylene blue adsorption value of the finally prepared biological activated carbon.

Specifically, the impregnated raw material is taken out from the aqueous solution of the activator, and the aqueous solution of the excess activator is optionally drained and then subjected to high-temperature heat preservation activation in, for example, a muffle furnace, wherein the draining of the aqueous solution of the excess activator can prevent the aqueous solution of the excess activator from corroding the muffle furnace.

Optionally, the step of activating comprises:

and (3) placing the impregnated raw material in a muffle furnace, heating to an activation temperature at a speed of 19-21 ℃/min, such as 20 ℃/min, and carrying out heat preservation activation for 30-90min, such as ensuring any one time or a time period between any two time values of 30min, 35min, 40min, 50min, 60min, 70min, 80min and 90min of activation, so as to effectively activate the raw material to change the raw material into the biological activated carbon.

Optionally, the preparation method of the biological activated carbon further comprises the steps of washing the obtained product with water to the same pH value as water after activation to remove impurities, then drying and grinding after washing, and sieving with a 20-40 mesh sieve after grinding to obtain the undersize product.

It should be noted that, because the hair and feather have certain differences, the optimal activation temperature has certain differences in the actual activation process.

Optionally, when the raw material is feather and the activating agent is phosphoric acid, the impregnated raw material is activated by heat preservation at any one or any two temperature ranges of 300-600 ℃, such as 300 ℃, 350 ℃, 400 ℃, 450 ℃, 500 ℃, 540 ℃ and 600 ℃; wherein, the feather is used as the raw material, the biological activated carbon prepared by activating with phosphoric acid is acidic (pH6-7), the yield is 32-45%, and the specific surface area of the biological activated carbon reaches 68-130m²The methylene blue adsorption value is 60-98 mg/g.

Optionally, when the raw material is hair and the activating agent is phosphoric acid, the impregnated raw material is activated at 300-500 ℃, for example, at any one or two temperature ranges of 300 ℃, 350 ℃, 400 ℃, 450 ℃ and 500 ℃; wherein, the hair is used as raw material, and is prepared by activating with phosphoric acidThe biological activated carbon is acidic (pH6-7), the yield is 11-23%, and the specific surface area of the biological activated carbon reaches 169-287m²The methylene blue adsorption value is 96-115 mg/g.

Optionally, when the raw material is feather and the activating agent is potassium hydroxide, the impregnated raw material is activated by heat preservation at any one or any two temperature ranges of 500-700 ℃, such as 500 ℃, 550 ℃, 600 ℃, 650 ℃, 700 ℃; wherein, the feather is used as the raw material, the biological activated carbon prepared by activating potassium hydroxide is alkaline (pH7-8), the yield is 8-15%, and the specific surface area of the biological activated carbon reaches 116-294m²The methylene blue adsorption value is 95-138 mg/g.

Optionally, when the raw material is hair and the activating agent is potassium hydroxide, the impregnated raw material is activated by heat preservation at any one or two temperature ranges of 400-700 ℃, such as 400 ℃, 450 ℃, 480 ℃, 500 ℃, 550 ℃, 600 ℃, 650 ℃, 700 ℃; wherein, the hair is used as the raw material, the biological activated carbon prepared by activating the potassium hydroxide is alkaline (pH7-8), the yield is 15-27%, and the specific surface area of the biological activated carbon reaches 150-²The methylene blue adsorption value is 68-80 mg/g.

Optionally, when the raw material is feather and the activating agent is zinc chloride, the impregnated raw material is activated by heat preservation at any one or two temperature ranges of 300-600 ℃, such as 300 ℃, 350 ℃, 400 ℃, 450 ℃, 500 ℃, 540 ℃ and 600 ℃; wherein, the feather is used as the raw material, the bioactive carbon prepared by zinc chloride activation is acidic (pH6-7), the yield is 23-49%, and the specific surface area of the bioactive carbon reaches 165-365m²The methylene blue adsorption value is 84-145 mg/g.

Optionally, when the raw material is hair and the activating agent is zinc chloride, the impregnated raw material is activated by heat preservation at any one or two temperature ranges of 300-500 ℃, such as 300 ℃, 350 ℃, 400 ℃, 450 ℃, 500 ℃; wherein, the hair is used as the raw material, the biological activated carbon prepared by activating the zinc chloride is slightly acidic (pH6-7), the yield is 12-24.5%, and the specific surface area of the biological activated carbon reaches 142-²A/g, methylene groupThe blue adsorption value is 50-72 mg/g.

That is, the specific surface area and methylene blue adsorption value of the biological activated carbon prepared by different raw materials and different activators are different, and the biological activated carbon can be selected by a person skilled in the art according to actual needs.

In conclusion, the biological activated carbon provided by the application has the advantages of large specific surface area and high methylene blue adsorption value, can replace the traditional activated carbon prepared from wood, carbon and the like, and can be applied to liquid-phase decolorization, heavy metal adsorption, wastewater purification and the like.

The features and properties of the present application are described in further detail below with reference to examples.

In the examples provided in the present application, the method for determining the yield of the bio-activated carbon is as follows: after drying the above-mentioned bio-activated carbon at 110 ℃ for 10 hours, the mass percentage of the bio-activated carbon at that time to the mass of the dried raw material was calculated.

The determination method of the methylene blue adsorption performance determination basis of the biological activated carbon comprises the following steps: the national standard GB/T12496.10-1999 test method of wooden activated carbon: determination of methylene blue adsorption value. Wherein the unit of methylene blue adsorption value is mg/g.

The specific surface area of the biological activated carbon is measured by a Tristar3000analyzer specific surface area analyzer (Micromeritics, USA); the specific surface area is calculated according to the Brunaue-Emmett-Teller (BET) equation, and the specific surface area is expressed in m²/g。