Targeted Decomplexation of Metal Complexes for Efficient Metal Recovery by Ozone/Percarbonate

Abstract

Traditional methods cannot efficiently recover Cu from Cu(II)− EDTA wastewater and encounter the formation of secondary contaminants. In this study, an ozone/percarbonate (O 3 /SPC) process was proposed to efficiently decomplex Cu(II)−EDTA and simultaneously recover Cu. The results demonstrate that the O 3 /SPC process achieves 100% recovery of Cu with the corresponding k obs value of 0.103 min −1 compared with the typical • OH-based O 3 /H 2 O 2 process (81.2%, 0.042 min −1 ). The carbonate radical anion (CO 3 •− ) is generated from the O 3 /SPC process and carries out the targeted attack of amino groups of Cu(II)−EDTA for decarboxylation and deamination processes, resulting in successive cleavage of Cu−O and Cu−N bonds. In comparison, the • OH-based O 3 /H 2 O 2 process is predominantly responsible for the breakage of Cu−O bonds via decarboxylation and formic acid removal. Moreover, the released Cu(II) can be transformed into stable copper precipitates by employing an endogenous precipitant (CO 3 2−), accompanied by toxic-free byproducts in the O 3 /SPC process. More importantly, the O 3 /SPC process exhibits excellent metal recovery in the treatment of real copper electroplating wastewater and other metal−EDTA complexes. This study provides a promising technology and opens a new avenue for the efficient decomplexation of metal−organic complexes with simultaneous recovery of valuable metal resources.

Defect-Induced Synergetic Effect of Bi-Based Compounds for One-Pot Conversion of Organic Pollutants into CO via Coupling Photodegradation of Carbamazepine with Photoreduction of CO2

“…DFT calculations were performed to determine the work function of the catalysts to probe the flow and charge transfer between the interfaces. 29,30 As shown in Figure 3b, the calculation results exhibit BiVO 4 with high-level work function (6.88 eV) while BiOBr results in a lower work function of 5.60 eV. Combined with the test of the band gap, the initial state of the band structure diagram of BiVO 4 and BiOBr before contact is shown in Figure 3c, left.…”

“…As shown in Figure a, the high-resolution XPS pattern of O 1s revealed the signals belonging to the Bi–O bond in BiOBr/BiVO 4 were shifted to higher binding energy compared with those in BiOBr while showing an opposite trend with BiVO 4 , indicating a lower electron density around BiVO 4 in hybrids. , Therefore, it can be speculated that there existed a strong electron interaction that induced the electron transfer from BiOBr to BiVO 4 . DFT calculations were performed to determine the work function of the catalysts to probe the flow and charge transfer between the interfaces. , As shown in Figure b, the calculation results exhibit BiVO 4 with high-level work function (6.88 eV) while BiOBr results in a lower work function of 5.60 eV. Combined with the test of the band gap, the initial state of the band structure diagram of BiVO 4 and BiOBr before contact is shown in Figure c, left.…”

Controllable Pyridine N-Oxidation–Nucleophilic Dechlorination Process for Enhanced Dechlorination of Chloropyridines: The Cooperation of HCO4– and HO2–

“…The experimental solutions used in this study were all prepared with Milli-Q ultrapure water (with a specific conductivity of >18.2 MΩ cm). The strain used for toxicity testing was Vibrio qinghaiensis sp.-Q67 from the Department of Biology at East China Normal University . The real Cl–Py wastewater was collected from a company in Jiangxi Province (Cl–Py: 31.4 mg L –1 , NO 3 – : 75.5 mg L –1 , NH 4 + : 12.0 mg L –1 , Cl – : 21.6 mg L –1 , COD: 212.5 mg L –1 , pH = 8.4).…”

“…The strain used for toxicity testing was Vibrio qinghaiensis sp.-Q67 from the Department of Biology at East China Normal University. 28 The real Cl−Py wastewater was collected from a company in Jiangxi Province (Cl−Py: 31.4 mg L −1 , NO 3 − : 75.5 mg L −1 , NH 4 + : 12.0 mg L −1 , Cl − : 21.6 mg L −1 , COD: 212.5 mg L −1 , pH = 8.4).…”

Contradictory role of reactive oxygen species in dissolution-dependent activity of Pb-based anodes in acidic electrooxidation

“…38 Electron paramagnetic resonance (EPR) measurements were performed for the detection of cOH and SO 4 c − . 39 DMPO was used as the capturing agent for cOH and SO 4 c − . 38 The DMPO-containing electrolyte samples were used in electrochemical samples.…”