几种果壳类生物质炭的制备和性能

Preparation and characterization of biochar from some kinds of nut shell

生物质炭作为一种多功能吸附材料正逐步受到人们的广泛关注.本文以花生壳、核桃壳、栗子壳等废弃生物质为原料制备生物质炭,研究了制备生物质炭的主要工艺,进一步对原材料的组成成分,制备的生物质炭的得率、元素分析、微观结构、碘吸附值等性质进行测定.结果表明,三种原材料中固定炭的含量趋势为花生壳〉栗子壳〉核桃壳.挥发分的含量为核桃壳〉花生壳〉栗子壳.比较了300℃、500℃、650℃三种温度下制备的生物质炭的性质,结果显示,随着温度的增加,生物质炭的得率逐渐减少,炭含量逐渐增加,并且炭表面的孔隙越丰富,褶皱越明显.在此基础上比较了炭材料的碘吸附能力,结果表明,碘吸附能力最高的是花生壳,其次是核桃壳、栗子壳.其中花生壳在650℃制备的生物质炭碘吸附值能达到685 mg/g.

Biochar as one of multifunctional adsorption material was widely concerned. In this paper, the main preparation technology of biochar with waste peanut shell, chestnut shell, walnut shell was researched. The raw material composition, biochar yield, hioehar elemental analysis, microscopic structure and the iodine adsorption value were tested. The results showed that the trend of fixed carbon in four kinds of raw material content is peanut shell 〉 chestnut shell 〉 walnut shell. The trend of volatile matter content is walnut shell 〉 chestnut shell 〉 peanut shell. The properties of 300 ℃, 500 and 650 ℃ three kinds of biochar were compared, the results also showed that the biochar yield decreased, the carbon content increased and the surface has more rich pore and obvious fold with the increase of temperature. Comparison of the iodine adsorption value of different biochars were cmxied out, the results indicated that the highest iodine adsorption capacity was peanut shell. The peanut shell at 650 ℃ preparation of biochar iodine adsorption value can reach 685 mg/g.