College of Materials Science and Engineering, Nanjing Forestry University, Nanjing, 210037, China.
Department of Chemical and Biomolecular Engineering, University of California, Berkeley, CA, 94720, USA.
Sci Rep. 2018 Jun 22;8(1):9501. doi: 10.1038/s41598-018-27777-4.
This study explores the effect of carbon sphere preparation conditions on the morphology of the carbon spheres and the micropore development by fast potassium hydroxide activation via microwave heating. Enzymatic hydrolysis lignin is used as the precursor for carbon sphere preparation via environmentally friendly hydrothermal carbonization. The effects of various carbonization temperatures, carbonization times and reaction concentrations on the physical morphology of the carbon sphere surfaces are investigated. The Brunauer-Emmett-Teller surface area, yield and scanning electron microscopic images are used to characterize the carbon spheres. High carbonization temperatures and times result in large particle sizes, high sphericity, uniform size, and high dispersity of the carbon spheres. The best carbon spheres are obtained at 270 °C for 7 hours with a reaction concentration of 0.06 g ml and a particle size of 3-6 μm. After activation, the Brunauer-Emmett-Teller surface area of the activated carbon spheres increases from 248 m g to 1278 m g. Carbon spheres activated by treatment with fast potassium hydroxide and microwave heating can develop micropores that enhance the adsorptive capacity for small molecules, such as gases. Enzymatic hydrolysis lignin-derived carbon spheres formed via hydrothermal carbonization should be potentially sustainable materials applicable in energy and environmental fields.
本研究通过微波加热快速氢氧化钾活化，探讨了碳球制备条件对碳球形态和微孔发展的影响。采用环境友好的水热碳化法，以酶解木质素为前驱体制备碳球。考察了不同碳化温度、碳化时间和反应浓度对碳球表面物理形态的影响。采用比表面积、产率和扫描电子显微镜图像对碳球进行了表征。高碳化温度和时间导致碳球粒径大、球形度高、粒径均匀、分散性好。在反应浓度为 0.06g/ml、碳化时间为 7 小时、碳化温度为 270°C 的条件下，得到了最佳的碳球，粒径为 3-6μm。活化后，活性炭球的比表面积从 248m2/g 增加到 1278m2/g。用快速氢氧化钾和微波加热处理得到的碳球可以开发出微孔，从而增强对小分子（如气体）的吸附能力。通过水热碳化法由酶解木质素衍生的碳球应该是一种有潜力的可持续材料，可应用于能源和环境领域。
