Adsorptive removal of dyes using char derived from anaerobic digestate

Research Poster
Shyam Sivaprasad
Ajay Shah
Department of Food, Agricultural and Biological Engineering

Hydrothermal carbonization (HTC) of waste biomass has garnered attraction lately owing to the potential application of hydrochar in soil amendment and pollution remediation. This study focuses on the utilization of Anaerobic digested effluent (ADE) obtained from wastewater treatment plant as adsorbent. The ADE was hydrothermally carbonized in a 1 L parr reactor at 200 oC for 1 hour to produce hydrochar. Pre-dried ADE and hydrochar were activated at 200 oC & 400 oC for 2 hours to further be used in adsorption studies. The performance of these adsorbents were also compared with Commercial activated carbon (CAC). Methylene blue (MB) and Methyl orange (MO) are prevalently used industrial dyes and are considered as representative adsorbate compounds for cationic and anionic dyes respectively. Effect of adsorbate concentration on different adsorbents were studied. It is observed that a maximum uptake content of 103.743 ± 9.264 mg/g was obtained for hydrochar activated at 400 oC at 1g/L dosage for Methylene blue and 35.260 ± 5.586 mg/g for Methyl orange. The maximum removal (%) was found to be 91.958 ± 2.604 for 10 ppm of Methylene blue at 1g/L dosage of hydrochar activated at 400 oC and 71.808 ± 4.265 for 10 ppm of Methyl orange. The plausible governing mechanism is strong electrostatic interaction between adsorbent and adsorbate which led to the enhanced adsorption of Methylene blue.