Abdulsalam Jibril, Otun Kabir, Gardee Nasreen, Patel Bilal, Leswifi Taile, Mathe Mahlanyane Kenneth
Department of Chemical Engineering, University of South Africa, Florida Park, Roodepoort, Johannesburg1709, South Africa.
Institute for the Development of Energy for African Sustainability, University of South Africa, Florida Park, Roodepoort, Johannesburg1709, South Africa.
ACS Omega. 2023 Jan 31;8(6):5285-5299. doi: 10.1021/acsomega.2c05887. eCollection 2023 Feb 14.
The valorization of a South African paper mill waste sludge into an activated biocarbon electrode material for energy storage application is reported. The valorization method is a two-step synthesis that comprises hydrothermal carbonization and NaOH activation of paper mill waste at 700 °C to produce activated biocarbon. The development of high porosity carbon material with a surface area of 1139 m/g was observed. The synthesized biocarbon electrode exhibited good specific capacitance ( ) values of 206 and 157 Fg, from a three-electrode cell in neutral (1 M NaSO) and alkali (3 M KOH) electrolytes, respectively. The electrolyte concentration purportedly has a considerable effect on specific capacitance. In both electrolytes, symmetric triangular curves in galvanostatic charge-discharge point to a quick charge-discharge process. Synthesized material testing with a two-electrode cell in 3 M KOH and 1 M NaSO electrolytes, respectively, delivered specific capacitances of 125 and 152 Fg, with the corresponding energy densities of 17.4 and 21.1 Wh kg. The material had capacity retention efficiencies of 83 and 92% after 5000 cycles in 3 M KOH and 1 M NaSO electrolytes, respectively. The electrode material performance of the activated biocarbon from paper sludge clearly shows its potential for electrochemical energy storage. The reported results present an exciting potential contribution of the pulp and paper industry toward the transition to green energy.
报道了将南非造纸厂的废污泥转化为用于储能应用的活性生物碳电极材料。该转化方法是一种两步合成法，包括水热碳化和在700℃下对造纸厂废料进行NaOH活化以生产活性生物碳。观察到开发出了表面积为1139 m/g的高孔隙率碳材料。合成的生物碳电极在中性（1 M NaSO）和碱性（3 M KOH）电解质的三电极电池中分别表现出206和157 F/g的良好比电容值。据称电解质浓度对比电容有相当大的影响。在两种电解质中，恒电流充放电中的对称三角曲线表明充放电过程很快。分别在3 M KOH和1 M NaSO电解质中用两电极电池对合成材料进行测试，得到的比电容分别为125和152 F/g，相应的能量密度分别为17.4和21.1 Wh/kg。该材料在3 M KOH和1 M NaSO电解质中经过5000次循环后，容量保持效率分别为83%和92%。造纸污泥中活性生物碳的电极材料性能清楚地显示了其在电化学储能方面的潜力。报道的结果展示了制浆造纸工业对向绿色能源转型的令人兴奋的潜在贡献。
