CN103588200B - Production method of xyloid coal-based shaped active carbon - Google Patents

Abstract

The present invention is a method for forming activated carbon based on woody coal, which includes: (1) mixing sawdust and coal powder in proportion, soaking them in phosphoric acid solution, taking them out, putting them into an oil bath, and plasticizing until the color of the mixture changes from brown to When it turns black and produces a large viscosity, the plasticization is ended to obtain a plasticized product; (2) The obtained plasticized product is quickly transferred to the mold, and formed on a hydraulic press, and the pressed carbon precursor molding is placed Slow constant temperature drying and hardening in a drying oven; (3) carbonization and activation of the prepared shaped carbonaceous precursor in an activation furnace to obtain a woody coal-based shaped activated carbon. Advantages: It overcomes the pollution, high cost, difficulty in transportation and storage, poor stability, poor compatibility, complicated process and other defects caused by the addition of adhesives in the traditional process; the invention uses wood chips to play a role similar to adhesives, Some wood chips replace coal powder to reduce the consumption of coal powder resources.

Description

A kind of production method of woody coal-based shaped activated carbon

technical field

The invention relates to a production method of woody coal-based shaped activated carbon, which belongs to the technical field of novel activated carbon composite preparation.

Background technique

Activated carbon is an important material involved in many fields of military, civil and industry. Coal-based activated carbon is currently the largest activated carbon product at home and abroad. The preparation process of coal-based shaped activated carbon is generally: the raw coal is first crushed and pulverized, then mixed with a binder, shaped by molding equipment, and the shaped material is then carbonized and activated. Commonly used binders are: coal tar, coal tar pitch and petroleum pitch. The use of these adhesives increases the production cost on the one hand, and there are some problems. Such as coal tar pollution, high cost, insulation operation, transportation and storage difficulties; coal tar pitch poor stability, toxic and smelly; petroleum pitch and coal poor compatibility. These preparation methods have the problem of adhesive usage cost.

Contents of the invention

The present invention proposes a production method of woody coal-based shaped activated carbon, the purpose of which is to prepare woody coal-based activated carbon by using biomass sawdust as an adhesive without adding an adhesive and reducing the consumption of coal powder. Formed activated carbon solves the problems of adhesive use cost and non-renewable coal energy in traditional preparation methods.

Technical solution of the present invention: a method for forming activated carbon based on woody coal, characterized in that: the method includes the following process steps:

(1) Mix sawdust and coal powder in proportion, immerse them in a phosphoric acid solution with a mass concentration of 30%~50%, take them out, put them in an oil bath, and plasticize them at 150~190°C until the color of the mixture changes from brown to black , and produce a viscosity of about 1.5Pa·s, the plasticization is ended to obtain a plasticized product;

(2) Quickly transfer the obtained plasticized product to the mold, and shape it under the pressure of 30MPa in a hydraulic press, and place the pressed carbon precursor molding in a drying oven (temperature 80~100°C) for slow constant temperature drying for about 1 hour, hardening;

(3) Carbonize the prepared shaped carbon precursor in an activation furnace (carbonization temperature 300~500°C, carbonization time 1~2h) and activation (activation temperature 400~600°C, activation time 1~3 h) , to produce woody coal-based shaped activated carbon, the activated carbon diameter is 3mm, the length is 10-20mm, and the strength is 80%~90%, which is not a unit of strength. [Explanation: Refer to the national standard "GB/T12496.6 Wooden Activated Carbon Test Method" for the determination of strength]

Advantages of the present invention: In the traditional coal-based activated carbon preparation process, the addition of adhesives has problems such as large pollution, high cost, heat preservation operation, difficulty in transportation and storage, poor stability, poisonous and odorous, poor compatibility, etc. , and increased process complexity and production costs. Coal powder is a non-renewable energy source, and wood chips are renewable energy sources. It is of practical significance to use part of wood chips instead of coal powder to reduce the consumption of coal powder resources. The invention effectively solves the problem of using the adhesive and reduces the consumption of pulverized coal.

Description of drawings

Accompanying drawing 1 is process flow chart of the present invention.

Detailed ways

As shown in the accompanying drawings, a method for woody coal-based shaped activated carbon comprises the following process steps:

(1) Mix sawdust and coal powder in proportion, immerse them in a phosphoric acid solution with a mass concentration of 30%~50%, take them out, put them in an oil bath, and plasticize them at 150~190°C until the color of the mixture changes from brown to black , and produce a viscosity of about 1.5Pa·s, the plasticization is ended to obtain a plasticized product;

(2) Quickly transfer the obtained plasticized product to the mold, and shape it under the pressure of 30MPa in a hydraulic press, and place the pressed carbon precursor molding in a drying oven (temperature 80~100°C) for slow constant temperature drying for about 1 hour, hardening;

(3) Carbonize the prepared shaped carbon precursor in an activation furnace (carbonization temperature 300~500°C, carbonization time 1~2h) and activation (activation temperature 400~600°C, activation time 1~3 h) , to produce woody coal-based shaped activated carbon, activated carbon diameter 3mm, length 10~20mm, strength 80%~90%, 80%~90% is not a unit of strength. [Explanation: Refer to the national standard "GB/T12496.6 Wooden Activated Carbon Test Method" for the determination of strength]

The adhesive uses the adhesive effect of biomass sawdust, and at the same time reduces the consumption of pulverized coal without adding adhesive, and does not add adhesive.

The process parameters for preparing the shaped carbonaceous precursor are: impregnation with phosphoric acid with a mass concentration of 30% to 50%, impregnation temperature at 50°C to 70°C, plasticization temperature at 150°C to 190°C, mass ratio of wood chips to coal powder It is 1:1~1:4, the mass ratio of sawdust and phosphoric acid is 1:1~1:4, and the molding pressure is 30MPa.

The process parameters for the combination of wood-based activated carbon and coal-based activated carbon are: the impregnation ratio, that is, the mass ratio of phosphoric acid to the shaped carbon precursor, is 0:1~2:1, the activation temperature is 400~600°C, and the activation time is 1 h~3 h.

Example 1

Crush wood chips to 30 mesh and coal powder to 200 mesh, mix them at a mass ratio of 1:4, and then soak them in 30% phosphoric acid solution, then take them out and plasticize them in an oil bath at 180°C until the color of the mixture changes from brown to black. And when a greater viscosity is produced, the plasticization is ended and a plasticized product is obtained. The obtained plasticized product is quickly transferred to the mold and formed on the hydraulic press. The pressed carbonaceous precursor molding was slowly dried and hardened in a drying oven at a constant temperature, and the strength of the shaped carbonaceous precursor was measured to be 93%. The shaped carbonaceous precursor is sent into a tube furnace for carbonization and activation at an activation temperature of 550°C and an activation time of 2.5 hours to prepare a woody coal-based shaped activated carbon with a diameter of 3 mm, a length of 10-20 mm, a strength of 88%, and an adsorption value of methylene blue of 210 mg. ·g ^-1 , iodine adsorption value 865 mg·g ^-1 .

The performance index of woody coal-based shaped activated carbon should be adjusted appropriately according to the specific molding process and activation process parameters.

Example 2

Crush wood chips to 40 mesh and coal powder to 200 mesh, mix them at a mass ratio of 1:3, soak them in 40% phosphoric acid solution, take them out and plasticize them in an oil bath at 190°C until the color of the mixture changes from brown to black. And when a greater viscosity is produced, the plasticization is ended and a plasticized product is obtained. The obtained plasticized product is quickly transferred to the mold and formed on the hydraulic press. The pressed carbonaceous precursor molding was slowly dried and hardened in a drying oven at a constant temperature, and the strength of the shaped carbonaceous precursor was measured to be 91%. The shaped carbonaceous precursor is then sent into a tube furnace for carbonization and activation at an activation temperature of 500°C and an activation time of 1.5 h to prepare a woody coal-based shaped activated carbon with a diameter of 3 mm, a length of 10-20 mm, a strength of 87%, and an adsorption value of methylene blue of 195 mg. ·g ^-1 , iodine adsorption value 825 mg·g ^-1 .

The performance index of woody coal-based shaped activated carbon should be adjusted appropriately according to the specific molding process and activation process parameters.

Example 3

Crush wood chips to 40 mesh and coal powder to 200 mesh, mix them according to the mass ratio of 1:2, soak them in 50% phosphoric acid solution, take them out and plasticize them in an oil bath at 170°C until the color of the mixture changes from brown to black. And when a greater viscosity is produced, the plasticization is ended and a plasticized product is obtained. The obtained plasticized product is quickly transferred to the mold and formed on the hydraulic press. The pressed carbonaceous precursor molding was slowly dried and hardened in a drying oven at a constant temperature, and the strength of the shaped carbonaceous precursor was measured to be 93%. The shaped carbonaceous precursor is sent into a tube furnace for carbonization and activation at an activation temperature of 600°C and an activation time of 2 hours to prepare a woody coal-based shaped activated carbon with a diameter of 3 mm, a length of 10-20 mm, a strength of 84%, and an adsorption value of methylene blue of 165 mg. ·g ^-1 , iodine adsorption value 795 mg·g ^-1 .

The performance index of woody coal-based shaped activated carbon should be adjusted appropriately according to the specific molding process and activation process parameters.

Claims (1)

1. the method for the base molded gac of xyloid coal, it is characterized in that: wood dust is broken to 30 orders, coal dust 200 order, flood in 30% phosphoric acid solution after 1:4 mixing in mass ratio completely, take out and in oil bath pan, be plasticized to mixture color at 180 DEG C become black by brown, and when producing larger viscosity, terminate plasticizing, obtain plastifying product; The plasticizing product obtained is quickly transferred on mould, shaping on a hydraulic press; In loft drier, carry out slow freeze-day with constant temperature, sclerosis by suppressing the carbonaceous forerunner forming composition obtained, recording shaping carbonaceous presoma intensity is 93%; Shaping carbonaceous presoma to send in tube furnace carbonization-activation under activation temperature 550 DEG C, soak time 2.5 h again, and be prepared into the base molded gac of xyloid coal, diameter 3mm, length 10-20mm, intensity is 88%, methylene blue adsorption value 210mgg ^-1, iodine sorption value 865mgg ^-1.