Heavy metals removal from sewage sludge with mixed chelators of N, N-bis(carboxymethyl) glutamic acid and citric acid

The mixed chelators (MC) of N, N-bis(carboxymethyl) glutamic acid (GLDA) and citric acid (CA), which were biodegradable chelating ligand, were employed to remove heavy metals from sewage sludge. The extraction of Cd, Cu, Zn, Mn, and Cr from sludge was studied under different experimental conditions. Results showed that the removal efficiencies of heavy metals from both sludges were the highest with MC of GLDA and CA at the molar ratio of 1:5. For the sludge of plant A, the extraction efficiencies increased with increasing contact time, but only slowly increase was observed after 24 h. However, for the sludge of plant B, the removal efficiencies were significantly decreased after 16 h, and sharply decreased after 24 h. The removal efficiencies of heavy metals decreased with the increase of the solution pH, while they increased with the increase of the solution concentration. For the sludge of plant A, single washing with 200 mmol·L-1 MC might be favourable to remove heavy metals. However, for the sludge of plant B, duplicate washing with 100 mmol·L-1 MC could remove much more heavy metals. The concentration of Cu in sludge of plant B decreased from 695.79-139.16 mg·kg-1, which was conformed to the standard (GB 4284-2018). These results suggested that MC may be useful and environmentally friendly chelators in the removal of heavy metals from sewage sludge.

Medienart:

E-Artikel

Erscheinungsjahr:

2022

Erschienen:

2022

Enthalten in:

Zur Gesamtaufnahme - volume:43

Enthalten in:

Environmental technology - 43(2022), 2 vom: 31. Jan., Seite 255-263

Sprache:

Englisch

Beteiligte Personen:

Guo, Xiaofang [VerfasserIn]
Chen, Yulong [VerfasserIn]
Han, Wei [VerfasserIn]
Wang, Lu [VerfasserIn]
Gao, Libing [VerfasserIn]
Zhang, Guixiang [VerfasserIn]
He, Qiusheng [VerfasserIn]

Links:

Volltext

Themen:

2968PHW8QP
3KX376GY7L
Chelating Agents
Citric Acid
Citric acid
Glutamic Acid
Heavy metals
Journal Article
Metals, Heavy
Mixed chelators
N, N-bis(carboxymethyl) glutamic acid
Sewage
Sewage sludge

Anmerkungen:

Date Completed 24.01.2022

Date Revised 24.01.2022

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1080/09593330.2020.1783373

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM311229603