酒糟基炭材料的制备及应用

Preparation and application of distiller’s grains-based carbon materials

酒糟是乙醇工业和酿酒工艺产生的主要固体生物质废弃物,具有来源广泛、含碳量高、元素种类丰富等特点。酒糟在经过发酵、蒸馏等处理之后,仍含有丰富纤维素、木质素、粗蛋白和淀粉等物质,是理想的生物质炭材料前驱体。酒糟基炭材料是以酒糟为碳源,通过高温热解和水热处理等炭化方式,以及经过物理、化学等活化方式制备得到的炭材料。因其碳含量高、比表面积大、孔隙结构和元素种类丰富等特点,受到广泛关注和研究。综述了酒糟基炭材料的原料组成、制备方法及其在不同领域的应用,为今后对酒糟基炭材料的进一步研究提供了系统参考。首先分析了前驱体酒糟的来源和组成,不同地区、不同酿造方法产生的酒糟组成有所不同,主要体现为纤维素、木质素和粗蛋白等成分比例,以及N、S、P等元素质量分数的差别。然后总结对比了目前研究中典型的酒糟基炭材料制备方法,包括热解法、水热法和活化方法等,并展望了在未来酒糟基炭材料研究中可采取的先进制备方法。此外,介绍了目前酒糟基炭材料在能源(超级电容器、电池)、环境(重金属离子吸附、污水净化)、农业(土壤改善、缓释肥载体)和催化领域(氧还原、有机污染物降解)等方面的应用进展。最后,对现阶段酒糟基炭材料研究和应用过程中存在的问题及未来发展前景进行了展望。

Distiller’s grains are the main solid biomass waste from the ethanol industry and the brewing process,featuring a wide range of sources,high carbon content,and a rich variety of elements.Owing to rich cellulose,lignin,crude protein and starch after fermentation and distillation,the distiller’s grains are the ideal precursors for biomass carbon materials.Distiller’s grains-based carbon materials are prepared by high-temperature pyrolysis or hydrothermal treatment as well as physical or chemical activation,using distiller’s grains as the carbon source.Because of their high carbon content,large specific surface area,pore structure and rich variety of elements,the distiller’s grains-based carbon materials have been widely concerned and studied.Herein,the current research status of the distiller’s grains-based carbon materials is reviewed in terms of raw material composition,preparation methods and applications fields.For the distiller’s grains produced by different regions and brewing methods,the main differences lay in the ratio of components such as cellulose,lignin and crude protein, and in the content of elements such as N, S and P. Typical preparation methods of the distiller’s grains-based carbon materials are summarized and compared, including pyrolysis, hydrothermal method and activation method. Also, the development tendency of preparation method is pointed out. In addition, the progress of current applica-tions of the distiller’s grains-based carbon materials in energy (supercapacitors, batteries), environment (heavy metal ion adsorption, sewage purification), agriculture (soil improvement, slow-release fertilizer carrier) and catalytic fields (oxygen reduction, organic pollutant degradation) are introduced. Finally, the problems in the preparation and application of the distiller’s grains-based carbon materials are proposed, and their future development and application are prospected.