Roles of intrinsic Mn3+ sites and lattice oxygen in mechanochemical debromination and mineralization of decabromodiphenyl ether with manganese dioxide

Chai, Huijuan; Zhang, Zhimin; Zhou, Yuqi; Zhu, Lihua; Lv, Hanqing; Wang, Nan

doi:10.1016/j.chemosphere.2018.04.160

Cited by 31 publications

(10 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…During the ball milling, PS is activated to produce SO 4 •– , and the metal oxide generates oxygen vacancies and free electrons due to a collateral effect of losing lattice oxygen. ,, To confirm such reactive species during the milling of Al 2 O 3 and PS, we first employed DPPH• as a probe of free electrons and radicals. When the mixture of DPPH• and Al 2 O 3 is subjected to the ball milling, the absorption peak of DPPH• at 525 nm significantly decreased with the appearance of a new peak approximately 425 nm corresponding to DPPH – (Figure a), , which indicates the generation of free electrons on the milled Al 2 O 3 (eq ).…”

Section: Resultsmentioning

confidence: 99%

Complete Defluorination and Mineralization of Perfluorooctanoic Acid by a Mechanochemical Method Using Alumina and Persulfate

Wang

Zhou

et al. 2019

Environ. Sci. Technol.

Self Cite

View full text Add to dashboard Cite

Perfluorooctanoic acid (PFOA) is a persistent organic pollutant that has received concerns worldwide due to its extreme resistance to conventional degradation. A mechanochemical (MC) method was developed for complete degradation of PFOA by using alumina (Al2O3) and potassium persulfate (PS) as comilling agents. After ball milling for 2 h, the MC treatment using Al2O3 or PS caused conversion of PFOA to either 1-H-1-perfluoroheptene or dimers with a defluorination efficiency lower than 20%, but that using both Al2O3 and PS caused degradation of PFOA with a defluorination of 100% and a mineralization of 98%. This method also caused complete defluorination of other C3∼C6 homologues of PFOA. The complete defluorination of PFOA attributes to Al2O3 and PS led to the weakening of the C–F bond in PFOA and the generation of hydroxyl radical (•OH), respectively. During the MC degradation, Al2O3 strongly anchors PFOA through COO––Al coordination and in situ formed from Lewis-base interaction and PS through hydrogen bond. Meanwhile, mechanical effects induce the homolytic cleavage of PS to produce SO4 •–, which reacts with OH group of Al2O3 to generate •OH. The degradation of PFOA is initiated by decarboxylation as a result of weakened C–COO– due to Al3+ coordination. The subsequent addition of •OH, elimination of HF, and reaction with water induce the stepwise removal of all carboxyl groups and F atoms as CO2 and F– , respectively. Thus, complete defluorination and mineralization are achieved.

show abstract

Section: Resultsmentioning

confidence: 99%

Complete Defluorination and Mineralization of Perfluorooctanoic Acid by a Mechanochemical Method Using Alumina and Persulfate

Wang

Zhou

et al. 2019

Environ. Sci. Technol.

Self Cite

View full text Add to dashboard Cite

show abstract

“…The presence of lattice oxygen would make the catalyst have more excellent oxidation ability, so it had excellent catalytic activity. [63,64] Cat-2 had the lowest reduction temperature, which suggested that high reduction performance is one of the factors that enhanced the catalyst's oxidation of toluene. In general, the special advantages of crystal structure, active oxygen and element valence made the catalyst show the best activity.…”

Section: Discussionmentioning

confidence: 99%

“…Lattice oxygen was an important substance that affects the catalytic performance of the catalyst. The presence of lattice oxygen would make the catalyst have more excellent oxidation ability, so it had excellent catalytic activity [63,64] . Cat‐2 had the lowest reduction temperature, which suggested that high reduction performance is one of the factors that enhanced the catalyst‘s oxidation of toluene.…”

Section: Discussionmentioning

confidence: 99%

MnO_x Catalyst with High‐Efficiency Degradation Behavior of Toluene: Effect of Cryptomelane

Zhang

Qin

et al. 2022

ChemistrySelect

View full text Add to dashboard Cite

A series of MnOx catalysts were prepared by hydrothermal reaction of different pH values, which proved the important influence of preparation conditions on the structure and performance of the catalysts. The results proved that the cryptomelane MnOx catalyst with a pH of 10 (Cat‐2) exhibited the most outstanding performance in catalyzing toluene. The appearance of cryptomelane on Cat‐2 would reduce the chemical valence of Mn, which could increase the content of Mn3+ and the amount of oxygen vacancies. With the increase of Mn3+, the Mn−O bond was broken more easily, and then facilitated the mobility oxygen species, causing the promotion of the catalytic activity. Low‐valence manganese, high‐capacity oxygen vacancies and maximum concentration of lattice oxygen were the most important reasons for the best catalytic activity of Cat‐2. According to the results of in‐situ DRIFT, benzyl, benzaldehyde, benzoic acid were the main intermediate products, which followed the Mars‐van Krevelen mechanism.

show abstract

“…Fig. 2(d) shows that the O 1s peak was deconvoluted into two peaks at 531.5 and 530.3 eV corresponding to the adsorption oxygen (Oads) and lattice oxygen (Olat), respectively [35,36]. The peak intensity of the lattice oxygen was much higher than that of the adsorption oxygen, which was different from that with BiOCl and Bi12O17Cl2 [37,38].…”

Section: Xps Analysismentioning

confidence: 94%

BiOCl-Bi12O17Cl2 nanocomposite with high visible-light photocatalytic activity prepared by an ultrasonic hydrothermal method for removing dye and pharmaceutical

Long

Xian

Zhang

et al. 2020

Chinese Journal of Catalysis

View full text Add to dashboard Cite

Roles of intrinsic Mn3+ sites and lattice oxygen in mechanochemical debromination and mineralization of decabromodiphenyl ether with manganese dioxide

Cited by 31 publications

References 37 publications

Complete Defluorination and Mineralization of Perfluorooctanoic Acid by a Mechanochemical Method Using Alumina and Persulfate

Complete Defluorination and Mineralization of Perfluorooctanoic Acid by a Mechanochemical Method Using Alumina and Persulfate

MnO_x Catalyst with High‐Efficiency Degradation Behavior of Toluene: Effect of Cryptomelane

BiOCl-Bi12O17Cl2 nanocomposite with high visible-light photocatalytic activity prepared by an ultrasonic hydrothermal method for removing dye and pharmaceutical

Contact Info

Product

Resources

About

Roles of intrinsic Mn3+ sites and lattice oxygen in mechanochemical debromination and mineralization of decabromodiphenyl ether with manganese dioxide

Cited by 31 publications

References 37 publications

Complete Defluorination and Mineralization of Perfluorooctanoic Acid by a Mechanochemical Method Using Alumina and Persulfate

Complete Defluorination and Mineralization of Perfluorooctanoic Acid by a Mechanochemical Method Using Alumina and Persulfate

MnOx Catalyst with High‐Efficiency Degradation Behavior of Toluene: Effect of Cryptomelane

BiOCl-Bi12O17Cl2 nanocomposite with high visible-light photocatalytic activity prepared by an ultrasonic hydrothermal method for removing dye and pharmaceutical

Contact Info

Product

Resources

About

MnO_x Catalyst with High‐Efficiency Degradation Behavior of Toluene: Effect of Cryptomelane