Subject: Chemical properties of activated carbon0053
Content: Petroleum coke, the by-product of oil refinery, is rich in resources, low in price, high in carbon content, low in ash and volatile, and is a high quality raw material for producing medium and high grade carbon.But because petroleum coke is easy graphitization carbon, compact structure, high crystallinity, lack of activation required by the primary hole, need to use a large number of strong alkali to activate the hole, resulting in high production cost, serious pollution. Therefore, optimizing the process conditions, reducing the amount of alkali and controlling the micropore structure are the key to the development of petroleum coke based activated carbon with high specific surface area on the basis of activation mechanism. Based on this, this paper focuses on the following aspects of exploration and research: Activated carbon was prepared by using Liaohua petroleum coke as raw material and KOH as activator. The effects of alkali-coke mixing mode, particle size of raw material, carrier gas flow rate, different chlorophyll immersion, drying and heating rate on the properties of activated carbon were investigated.The experimental results show that Liaohua petroleum coke is a high quality raw material for the preparation of activated carbon with high specific surface area. The mixing mode of alkali coke, the particle size of raw material and the velocity of activated gas all affect the performance of the product.The specific surface area of activated carbon was obtained in the following order: water ~ glacial acetic acid >, ethanol >, methanol ~ tetrahydroaromatic >, ethylene glycol >, 30% hydrogen peroxide, which indicated that the removal of potassium compounds in activated carbon particles had a great influence on the formation of activated carbon pores and the adsorption performance.The microcrystalline structure and surface properties of the raw materials were changed by pre-carbonization, and the effect of these changes on the properties of the activated products was emphatically investigated. At higher pre-carbonization temperature, with the increase of pre-carbonization temperature, the content of hydrogen and oxygen in petroleum coke decreases sharply, the content of surface functional groups also decreases, and the microcrystalline structure becomes more stable. As a result, activation is difficult, which leads to the reduction of specific surface area of activated carbon and the change of pore size distribution. The mesopore content increased relatively. activated carbon pellets wholesale The specific surface area of activated carbon prepared by untreated petroleum coke plus three times the mass of alkali activation is 1997m2g, while the specific surface area of activated carbon prepared by petroleum coke carbonized at 1200 ℃ under the same activation condition is only 12m2g1.However, the heat treatment of petroleum coke at lower temperature has little effect on the specific surface area of the activated carbon prepared, but increases the DOO of graphite microcrystals in the raw material.