Potential Use of Waste Activated Sludge Hydrothermally Treated as a Renewable Fuel or Activated Carbon Precursor

Molecules

E. Diaz¹  M.A. de la Rubia¹  A. F. Mohedano¹  J.A. Villamil² 

[1]Departamento de Ingenieria Química, Facultad de Ciencias, Universidad Autonoma de Madrid, Campus de Cantoblanco, 28049 Madrid, Spain

[2]Departamento de Tecnología Química y Ambiental, Universidad Rey Juan Carlos, 28933 Móstoles (Madrid), Spain

关键词: activated carbon;    adsorption;    chemical activation;    hydrothermal carbonization;    hydrochar;    low-cost adsorbent;   

DOI  :  10.3390/molecules25153534

来源: DOAJ

【 摘 要 】

In this work, dewatered waste activated sludge (DWAS) was subjected to hydrothermal carbonization to obtain hydrochars that can be used as renewable solid fuels or activated carbon precursors. A central composite rotatable design was used to analyze the effect of temperature (140–220 °C) and reaction time (0.5–4 h) on the physicochemical properties of the products. The hydrochars exhibited increased heating values (up to 22.3 MJ/kg) and their air-activation provided carbons with a low BET area (100 m²/g). By contrast, chemical activation with K₂CO₃, KOH, FeCl₃ and ZnCl₂ gave carbons with a well-developed porous network (BET areas of 410–1030 m²/g) and substantial contents in mesopores (0.079–0.271 cm³/g) and micropores (0.136–0.398 cm³/g). The chemically activated carbons had a fairly good potential to adsorb emerging pollutants such as sulfamethoxazole, antipyrine and desipramine from the liquid phase. This was especially the case with KOH-activated hydrochars, which exhibited a maximum adsorption capacity of 412, 198 and 146 mg/g, respectively, for the previous pollutants.

【 授权许可】

Unknown