TY - JOUR
T1 - Porous carbons derived from hydrothermally treated biogas digestate
AU - Bernardo, Maria
AU - Correa, Catalina Rodriguez
AU - Ringelspacher, Yvonne
AU - Becker, Gero C.
AU - Lapa, Nuno
AU - Fonseca, Isabel
AU - Esteves, Isabel A. A. C.
AU - Kruse, Andrea
N1 - info:eu-repo/grantAgreement/FCT/SFRH/SFRH%2FBPD%2F93407%2F2013/PT#
FCT/MCTES (UID/QUI/50006/2019.
FCT Investigator Project/Contract IF/01016/2014.
ERANet-LAC (ELAC2014/BEE-0367), funded by the European Commission.
The authors from the University of Hohenheim would like to thank the German Federal Ministry for Education and Research (BMBF) for funding this research (01DN15027). The authors would also like to thank QUANTACHROME GmbH & Co. KG for measuring the N2 and CO2 isotherms of the porous carbons.
PY - 2020/3/15
Y1 - 2020/3/15
N2 - Porous carbons from digestate-derived hydrochar were produced, characterized and their performance to reclaim phosphate from water was evaluated as a preliminary approach to demonstrate their practical application. In a first step, the digestate was converted into hydrochars through hydrothermal carbonization by using two different pH conditions: 8.3 (native conditions) and 3.0 (addition of H2SO4). The resulting hydrochars did not present significant differences. Consecutively, the hydrochars were activated with KOH to produce activated carbons with enhanced textural properties. The resulting porous carbons presented marked differences: the AC native presented a lower ash content (20.3 wt%) and a higher surface area (SBET = 1106 m2/g) when compared with the AC-H2SO4 (ash content = 43.7 wt% SBET = 503 m2/g). Phosphorus, as phosphate, is a resource present in significative amount in wastewater, causing serious problems of eutrophication. Therefore, the performance of the porous carbons samples to recover phosphate – P(PO4 3−) – from water was evaluated through exploitation assays that included kinetic studies. The lumped model presented a good fitting to the kinetic data and the obtained uptake capacities were the same for both carbons, 12 mg P(PO4 3−)/g carbon. Despite the poorer textural properties of AC-H2SO4, this carbon was richer in Ca, Al, Fe, K, and Mg cations which promoted the formation of mineral complexes with phosphate anions. The results obtained in this work are promising for the future development of P(PO4 3−) enriched carbons that can be used thereafter as biofertilizers in soil amendment applications.
AB - Porous carbons from digestate-derived hydrochar were produced, characterized and their performance to reclaim phosphate from water was evaluated as a preliminary approach to demonstrate their practical application. In a first step, the digestate was converted into hydrochars through hydrothermal carbonization by using two different pH conditions: 8.3 (native conditions) and 3.0 (addition of H2SO4). The resulting hydrochars did not present significant differences. Consecutively, the hydrochars were activated with KOH to produce activated carbons with enhanced textural properties. The resulting porous carbons presented marked differences: the AC native presented a lower ash content (20.3 wt%) and a higher surface area (SBET = 1106 m2/g) when compared with the AC-H2SO4 (ash content = 43.7 wt% SBET = 503 m2/g). Phosphorus, as phosphate, is a resource present in significative amount in wastewater, causing serious problems of eutrophication. Therefore, the performance of the porous carbons samples to recover phosphate – P(PO4 3−) – from water was evaluated through exploitation assays that included kinetic studies. The lumped model presented a good fitting to the kinetic data and the obtained uptake capacities were the same for both carbons, 12 mg P(PO4 3−)/g carbon. Despite the poorer textural properties of AC-H2SO4, this carbon was richer in Ca, Al, Fe, K, and Mg cations which promoted the formation of mineral complexes with phosphate anions. The results obtained in this work are promising for the future development of P(PO4 3−) enriched carbons that can be used thereafter as biofertilizers in soil amendment applications.
KW - Biogas production
KW - Biomass digestate
KW - Hydrothermal carbonization
KW - Nanoporous carbons
KW - Phosphate recovery from water
UR - http://www.scopus.com/inward/record.url?scp=85079355664&partnerID=8YFLogxK
U2 - 10.1016/j.wasman.2020.02.011
DO - 10.1016/j.wasman.2020.02.011
M3 - Article
C2 - 32070820
AN - SCOPUS:85079355664
SN - 0956-053X
VL - 105
SP - 170
EP - 179
JO - Waste Management
JF - Waste Management
ER -