Investigating the potential origin and formation of humic substances in biological wastewater treatment systems from the forms of phosphorus.
Environ Technol
; 42(13): 1979-1988, 2021 May.
Article
en En
| MEDLINE
| ID: mdl-31642393
ABSTRACT
Origin of the humic substances formed in biological wastewater treatment system (abbreviated as bio-HS) still remains inconclusive. In this study, the bio-HS that contained humic acid (HA) and fulvic acid (FA) from effluent and activated sludge were isolated and purified with XAD-8 resin and ion exchange resin, and then the molecular weight, functional groups, contents and forms of phosphorus (P) using gel permeation chromatography (GPC), fourier transform infrared (FTIR), element analysis and P nuclear magnetic resonance (31P-NMR) were investigated. The results showed that HS was formed in biological wastewater treatment systems, and had a lower degree of humification than soil, peat, or marine HS, and mainly comprised diester and monoester P fragments. Specific signal peaks of intracellular materials and cell membranes (nucleic acid, phospholipids, and sugar phosphate) showed that microbial cell debris was the precursor of bio-HS. HA comprised diester P fragments and monoester P fragments that formed when diester P fragments degraded, while FA contained only diester P fragments. The monoester P fragments in HA may result from microbial degradation of diester P fragments, and FA may simultaneously condense into HA. These results show that microbial cell debris was first transformed into FA and then into HA.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Purificación del Agua
/
Sustancias Húmicas
Idioma:
En
Revista:
Environ Technol
Asunto de la revista:
SAUDE AMBIENTAL
/
TOXICOLOGIA
Año:
2021
Tipo del documento:
Article