Mechanisms of Pb and/or Zn adsorption by different biochars: Biochar characteristics, stability, and binding energies

Efficient elimination of organic and inorganic pollutants by biochar and biochar-based materials

“…Adsorption capacity of biochar for metal endocrine disruptors (Hg 2+ , Pb 2+ , Cd 2+ ) was compared through DFT calculations, and the effect of oxygen-containing groups has been suggested for the high binding energy (Zhang et al 2019d). Besides, quantum chemistry calculations turned out that inner-sphere chemical complexation with functional groups was responsible for the adsorption of Cr(VI), Pb 2+ , and Zn 2+ (Zhao et al 2017(Zhao et al , 2020. On the other hand, a significant amount of theoretical research has gone into addressing the organic pollutants such as antibiotics, ionizable organic pollutants (IOPs), drugs, dyes, pesticide and so on (Peng et al 2016;Zhang et al 2018b;Jung et al 2015b;Wang et al 2016).…”

Qualitative and quantitative adsorption mechanisms of zinc ions from aqueous solutions onto dead carp derived biochar

“…13 Additionally, the calculated maximum monolayer adsorption capacities based on Langmuir model for CMBx were 80.65-87.72 mg g À1 . The observed maximum monolayer adsorption capacities of CMBx for Zn 2+ were higher than those of rice straw biochars (39.7 and 40.2 mg g À1 ), 18,28 chicken manure biochars (11.2 mg g À1 ), 18 sewage sludge biochars (4.3 mg g À1 ), 18 wheat straw biochars (41.8 mg g À1 ), 5 S. hermaphrodita biochars (48.1 mg g À1 ), 5 hardwood biochars (4.3 mg g À1 ) 27 and corn straw biochars (4.3 mg g À1 ), 27 suggesting that carp biochar was a promising one for Zn 2+ adsorption (Table S1 †). The R L values (ESI †) for CMB450, CMB550 and CMB650 were obtained in the range of 0.091-0.455, 0.063-0.357 and 0.032-0.217, respectively, indicating that the adsorption of Zn 2+ on CMBx was the favorable adsorption (0 < R L < 1).…”

“…hydroxyl and carboxyl groups). 18,20,34 Compared with the original biochar, the FTIR results of Zn 2+ loaded biochars showed that, aer Zn 2+ adsorption, the peaks at 3498, 3034 and 1649 cm À1 (assigned to the -OH, -CO-OH and C]C) had a signicant displacement and were broadened, indicating that the hydroxyl, carboxyl and C]C were involved in the adsorption process of Zn 2+ on CMBx. Analysis of the XPS wide scan spectra show that, aer Zn 2+ adsorption on CMB550, the photoelectron peaks of Zn 2p 1/2 and Zn 2p 3/2 appeared in the binding energy of 1022.13 eV and 1045.31 eV (Fig.…”

“…According to recently published research results, the mechanisms responsible for heavy metal adsorption on biochar mainly included physical adsorption, chemical precipitation, surface complexation with oxygen-containing functional groups (OFGs), cation exchange, electrostatic attraction, and cation-p interaction. [13][14][15][16][17][18] However, the relative contribution of these mechanisms for heavy metal adsorption on biochar largely varies with the type of biomass and pyrolysis temperature. Specically speaking, Zhao et al indicated that for the biochars derived from rice straw, chicken manure, and sewage sludge at 350 and 550 C, adsorption capacities and mechanisms for Pb 2+ and Zn 2+ were quite different.…”

Influence of Pyrolysis Temperature on the Heavy Metal Sorption Capacity of Biochar from Poultry Manure

“…The BET surface area of the investigated biochars reached the maximum value (19 m 2 ·g −1 ) for the BPM725 biochar which is high in comparison to the results obtained by other researchers. For example, in the work Zhao et al [ 37 ], the specific surface area of biochar produced at 550 °C was 7.09 m 2 ·g −1 . The adsorption–desorption isotherms for the investigated biochars are presented in Figure 2 .…”