TY - JOUR
T1 - The effect of Sol-Gel coatings on the phosphorus (P) adsorption capacity of calcareous materials for use in water treatment
AU - Jensen, Solvei Mundbjerg
AU - Søhoel, Helmer
AU - Blaikie, Frances Helen
AU - Brix, Hans
AU - Arias, Carlos Alberto
PY - 2022/1
Y1 - 2022/1
N2 - (1) Phosphorus (P) removal has proven difficult in decentralized wastewater treatment systems, and P binding material, installed as an external filter, has been proposed for improving P removal. Especially, calcium (Ca)-rich materials have shown promising results. (2) Five calcareous materials were tested with isotherm batch experiments. The material with the highest P adsorption capacity was selected to undergo different Sol-Gel coatings, i.e., different coating dilution ratios (1:10, 1:5, and 1:1) and exposure periods (5, 10, and 15 min). The seven coated materials were evaluated by isotherm experiments. (3) The maximum adsorption capacity (Q
max) was determined by fitting the Langmuir equation. Q
max for the non-coated materials, and ranged from 0.7 (sand) to 35.1 (Catsan) mg P g
−1 DW, while the coated materials ranged from 7.8 to 24.7 mg P g
−1 DW depending on the coating. Based on the rotated Principal Component Analysis, the most important parameters for Q
max were the texture and the Ca content. (4) Catsan was the most promising material, but when performing a Sol-Gel coating, a trade-off between preserving Q
max and the coating thickness were evident, as the materials with the thinner coating preserved more of the sorption capacity. The development of P binding materials constitutes a useful technology in decentralized wastewater treatment systems.
AB - (1) Phosphorus (P) removal has proven difficult in decentralized wastewater treatment systems, and P binding material, installed as an external filter, has been proposed for improving P removal. Especially, calcium (Ca)-rich materials have shown promising results. (2) Five calcareous materials were tested with isotherm batch experiments. The material with the highest P adsorption capacity was selected to undergo different Sol-Gel coatings, i.e., different coating dilution ratios (1:10, 1:5, and 1:1) and exposure periods (5, 10, and 15 min). The seven coated materials were evaluated by isotherm experiments. (3) The maximum adsorption capacity (Q
max) was determined by fitting the Langmuir equation. Q
max for the non-coated materials, and ranged from 0.7 (sand) to 35.1 (Catsan) mg P g
−1 DW, while the coated materials ranged from 7.8 to 24.7 mg P g
−1 DW depending on the coating. Based on the rotated Principal Component Analysis, the most important parameters for Q
max were the texture and the Ca content. (4) Catsan was the most promising material, but when performing a Sol-Gel coating, a trade-off between preserving Q
max and the coating thickness were evident, as the materials with the thinner coating preserved more of the sorption capacity. The development of P binding materials constitutes a useful technology in decentralized wastewater treatment systems.
KW - Adsorption isotherm experiments
KW - Constructed Wetlands (CWs)
KW - Decentralised wastewater treatment
KW - Filter
KW - Freundlich
KW - Langmuir
KW - Media
KW - Phosphorus (P)
KW - Sol-Gel coating
KW - Sorption
UR - http://www.scopus.com/inward/record.url?scp=85121707994&partnerID=8YFLogxK
U2 - 10.3390/w14010003
DO - 10.3390/w14010003
M3 - Journal article
SN - 2073-4441
VL - 14
JO - Water
JF - Water
IS - 1
M1 - 3
ER -