Adsorption and mechanism study for phenol removal by 10% CO2 activated bio-char after acid or alkali pretreatment.
J Environ Manage
; 348: 119317, 2023 Dec 15.
Article
in En
| MEDLINE
| ID: mdl-37857218
ABSTRACT
The development of an efficient bio-char used to remove phenol from wastewater holds great importance for environmental protection. In this work, wheat straw bio-char (BC) was acid-washed by HF and activated at 900 °C with 10% CO2 to obtain bio-char (B-â
¢-0.1D900). Adsorption experiments revealed that B-â
¢-0.1D900 achieved a remarkable phenol removal efficiency of 90% within 40 min. Despite its relatively low specific surface area of 492.60 m2/g, it exhibited a high maximum adsorption capacity of 471.16 mg/g. Furthermore, B-â
¢-0.1D900 demonstrated a good regeneration capacity for at least three cycles (90.71%, 87.54%, 84.36%). It has been discovered that HF washing, which removes AAEM and exposes unsaturated functional groups, constitutes one of the essential prerequisites for enhancing CO2 activation efficiency at high temperatures. After 10% CO2 activation, the mesoporous structure exhibited substantial development, facilitating enhanced phenol infiltration into the pores when compared to untreated BC. The increased branching of the bio-char culminated in a more complete aromatic system, which enhances the π-π forces between the bio-char and the phenol. The presence of tertiary alcohol structure enhances the hydrogen bonding forces, thereby promoting intermolecular multilayer adsorption of phenol. With the combination of various forces, B-â
¢-0.1D900 has a good removal capacity for phenol. This work provides valuable insights into the adsorption of organic pollutants using activated bio-char.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Water Pollutants, Chemical
/
Phenol
Language:
En
Journal:
J Environ Manage
Year:
2023
Type:
Article