Biochar from sewage sludge: preparation, characterization and ammonia-phosphorus capture

摘要

Sewage sludge was pyrolyzed in order to assess the effect of pyrolysis temperature on the yield of biochar production and its characteristics. The pyrolysis temperature was a key factor affecting biochar yield, while the highest yield was obtained at a temperature of 400°C. Biochar surface area increased with increasing pyrolysis temperature and was maximized (8.4 m~2/g), which was beneficial for capturing ammonia and phosphate in aqueous solution. Biochar removed 48.3-82.2% of ammonia at equilibrium time, whereas 35.4 to 69.6% was adsorbed onto biochar surface, implying that biochar is more efficient in removing cations than anions from aqueous solutions.