玻璃炭球的二步活化法 —— 一种高活化收率的途径(英文)

玻璃炭球的二步活化法 —— 一种高活化收率的途径(英文)

  • 摘要: 以玻璃炭球为原料,采用在干燥空气流中500℃高温热处理3h(第一步活化处理),而后在415℃低温处理不同时间(第二步活化处理)的两步活化法制取了一系列活性炭球。依据77K N2吸/脱附等温线,应用BET、αs-plot和BJH法测定了所得活性炭球的孔结构。结果表明:第一步活化处理后,在炭球表面生成少量大孔(中孔甚至大孔),这些大孔是第二步活化时活化气体(空气)的扩散入口,使得第二步活化处理时微孔的生成量增加。由此可以认为这种二步活化法是获得高收率的较高比面积和微孔容积活性炭的一种有效途径。

     

    Abstract: A series of activated carbons was prepared using a two-step activation process. The starting glass-like carbon spheres were heated at 500℃ for 3h (first step activation), and then at a low temperature, below 415℃, for different times (second step activation), in a flow of dry air. Their pore structures were evaluated from N2 gas adsorption/desorption isotherms at 77K by BET, αs-plot and BJH methods. The first step of activation generated a few large pores (mesopores and even macropores), on the surface of the spheres, which formed the entrance for the activating reagent gas (air), to increase micropores at a low temperature in the second step of activation. This two-step activation process was found to be an efficient approach to get a comparatively high surface area and a volume of micropores with a high activation yield.

     

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