Highly efficient nickel (II) removal by sewage sludge biochar supported α-Fe2O3 and α-FeOOH: Sorption characteristics and mechanisms

Abstract

A novel approach was employed to load α-Fe 2 O 3 and α-FeOOH onto sewage sludge biochar (SBC) with the purpose of efficient nickel (Ni) removal. A high Ni(II) adsorption capacity of 35.50 mg·g -1 in 100 ppm Ni(II) solution with 10 mg modified sewage sludge biochar (MSBC) was achieved. The adsorption kinetic and isotherm were fitted well by the pseudo-second-order model and the Langmuir model, respectively. The optimal pH was found around a neutral pH of 7. The adsorption mechanisms of Ni(II) onto MSBC were described as the synergistic effects of electrostatic attraction, ion exchange, inner-sphere complexation and co-precipitation. The initial rapid adsorption phenomenon could be attributed to electrostatic attraction and ion exchange, and then inner-sphere complexation and co-precipitation acted as a crucial role in the following step. The remarkable performance of MSBC provides an effective waste utilization approach to simultaneous sewage sludge recycle and Ni removal from aqueous solution.

Na4P2O7-Modified Biochar Derived from Sewage Sludge: Effective Cu(II)-Adsorption Removal from Aqueous Solution

“…However, the heavy-metal-adsorption capacity of sludge-based biochar is unsatisfactory, which limits its promotion and application to a certain extent [42, 43]. Some modifiers such as Fe 3 O 4 [44], nanostructured CaCO 3 [45], trithiocyanuric acid trisodium salt [46], α -Fe 2 O 3 and α -FeOOH [47], K 2 FeO 4 [48], and hydroxyapatite [42] have been successfully applied to prepare modified sewage sludge biochar, and satisfactory heavy-metal-adsorption capacity has been achieved. At present, chemical modification is a noteworthy research direction for improving the adsorption capacity of heavy metals by sewage sludge biochar [45, 49].…”

Production strategies and potential repercussion of sewage sludge biochar as a futuristic paradigm toward environmental beneficiation: A comprehensive review

“…The results showed that KOH activation produced biochar with a superior Pb(II) adsorption capacity (57.48 mg/g) than other examined biochar. For effective nickel (Ni) removal, Yang reported in his study (Yang et al, 2019) used a unique method to load 𝛼-Fe 2 O 3 and 𝛼-FeOOH onto SSB.…”

“…The results showed that KOH activation produced biochar with a superior Pb(II) adsorption capacity (57.48 mg/g) than other examined biochar. For effective nickel (Ni) removal, Yang reported in his study (Yang et al., 2019) used a unique method to load $$\alpha $$‐Fe 2 O 3 and $$\alpha $$‐FeOOH onto SSB. With 10 mg of modified SSB, a solution containing 100 ppm of Ni(II) was able to obtain a high Ni(II) adsorption capacity of 35.50 mg/g.…”

Hydrothermal Enhanced Nanoscale Zero-Valent Iron Activated Peroxydisulfate Oxidation of Chloramphenicol in Aqueous Solutions: Fe-Speciation Analysis and Modeling Optimization

“…Furthermore, FeOOH was believed to react with Fe 0 to generate Fe 3 O 4 due to no FeOOH being found in this study. Meanwhile, it has been demonstrated that Fe(OH) 3 can produce the mixture of FeOOH and α-Fe 2 O 3 at the range of 40-80 • C (Equation (15)) [63,64]. FeOOH could be converted to Fe 2 O 3 due to poor chemical stability (Equation (16)) [63].…”