APPLIED ORGANOMETALLIC CHEMISTRY
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2019
·Vol. 33
·期 3
·e4745
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IF 3.259
Yibing Xie,Langlang Wang,Ping Ning,Xueqian Wang,Qi Wang,Yingjie Zhang,Mengyu Wang
A series of Ce modified catalysts were prepared using equivalent-volumetric ultrasonic impregnation method for AsH 3 removal. The performance of catalytic oxidation of AsH 3 under dynamic conditions was studied under different synthesis and reaction conditions. Through screening tests, the optimum catalyst was impregnated by 10 wt.% Ce (CH 3 COO) 3 precursor and subsequently calcinated at 550 °C. When the reaction temperature reached 170 °C, the Ce-HZSM-5 catalyst could maintain an oxidation efficiency of over 90% in 82 hrs. Furthermore, the chemical structure and properties of the catalyst and its catalytic oxidation mechanism with AsH 3 were analyzed using SEM-EDS, BET, XRD, XPS, H 2 -TPR and FT-IR. The results showed that Ce mainly existed on the catalyst surface in the forms of Ce 4+ and Ce 3+ . In the reaction process, the chemisorbed oxygen played a key role in the transformation between the two valence states. AsH 3 was firstly oxidized to elemental As with the participation of lattice oxygen. Then, the elemental As was partially blown into the rear part of the adsorption column along with the air flow and subsequently, de-sublimed on the column wall. Herein, the elemental As remained on the surface of Ce-HZSM-5 catalyst, which would further oxidize to As 2 O 3 . For the recovery of As, Ce-HZSM-5 proved to be a promising catalyst in AsH 3 removal. Highlights The CeO x modified HZSM-5 catalyst was used to catalytic oxidation of AsH 3 . The Ce-HZSM-5 catalyst could maintain over 90% oxidation efficiency in 82 hrs. AsH 3 was catalytic oxidized to elemental As and H 2 O on the catalyst surface and the As can be collected. The As adsorbed on the catalyst surface can be oxidized to As 2 O 3 but cannot be further oxidized to As 2 O 5 .
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2022
·
IF 14.224
Kunlin Li,Jiayu Feng,Xingguang Hao,Xin Song,Changbin Zhang,Ping Ning,Kai Li
In this study, CuO@SiO 2 core-shell catalysts were successfully synthesized and applied to efficiently remove hazardous gaseous pollutant arsine (AsH 3 ) by catalytic oxidation under low-temperature and low-oxygen conditions for the first time. In typical experiments, the CuO@SiO 2 catalysts showed excellent AsH 3 removal activity and stability under low-temperature and low-oxygen conditions. The duration of the AsH 3 conversion rate above 90 % for the CuO@SiO 2 catalysts was 39 h, which was markedly higher than that of other catalysts previously reported in the literature. The considerable catalytic activity and stability were attributed to the protection and confinement effects of the SiO 2 shell, which resulted in highly dispersed CuO nanoparticles . Meanwhile, the strong interaction between the CuO core and SiO 2 shell further facilitated the formation of active species such as coordinatively unsaturated Cu 2+ and chemisorbed oxygen. The accumulation of oxidation products (As 2 O 3 and As 2 O 5 ) on the interface between the CuO core and SiO 2 shell and the pore channels of the SiO 2 shell is the main cause of catalysts deactivation . Furthermore, through combined density functional theory (DFT) calculations and characterization methods, a reaction pathway including gradual dehydrogenation (AsH 3 *→AsH 2 *→AsH*→As*) and gradual oxidation (2As*→As*+AsO*→2AsO*→As 2 O 3 ) for the catalytic oxidation of AsH 3 on CuO (111) surface was constructed to clarify the detailed reaction mechanism. The CuO@SiO 2 core-shell catalysts applied in this study could provide a powerful method for developing AsH 3 catalysts from multiple know AsH 3 removal systems.
研究领域:
环境科学
·
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2024
·
IF 10.8
Yibing Xie,Xueqian Wang,Zan Qu,Ping Ning,Langlang Wang,Haomiao Xu,Wenjun Huang,Jichang Lu,Jianfei Luo
The transformation of toxic arsine (AsH3) gas into valuable elemental arsenic (As0) from industrial exhaust gases is important for achieving sustainable development goals. Although advanced arsenic removal catalysts can improve the removal efficiency of AsH3, toxic arsenic oxides generated during this process have not received adequate attention. In light of this, a novel approach for obtaining stable As0 products was proposed by performing controlled moderate oxidation. We designed a tailored Ni-based catalyst through an acid etching approach to alter interactions between Ni and NaY. As a result, the 1Ni/NaY-H catalyst yielded an unprecedented proportion of As0 as the major product (65%), which is superior to those of other reported catalysts that only produced arsenic oxides. Density functional theory calculations clarified that Ni species changed the electronic structure of oxygen atoms, and the formed [NiIII–OH (μ-O)] active centers facilitated the adsorption of AsH2*, AsH*, and As* reaction intermediates for As–H bond cleavage, thereby decreasing the direct reactivity of oxygen with the arsenic intermediates. This work presents pioneering insights into inhibiting excessive oxidation during AsH3 removal, demonstrating potential environmental applications for recovery of As0 from toxic AsH3.
研究领域:
环境科学
·
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL
·
2024
·
IF 6.7
Jianfei Luo,Langlang Wang,Yibing Xie,Ping Ning,Yiran Xiong,Hang Zhang,Yixing Ma,Shao Zhang,Xueqian Wang
Existing processes for transforming arsine (AsH 3 ) into toxic arsenic oxides (As x O y ) through catalytic oxidation do not meet economic requirements. In contrast, the catalytic decomposition method stands out due to its ability to both remove AsH 3 and obtain elemental arsenic (As 0 ) as a valuable product. A series of blank molecular sieves (HZSM-5, 13X, MCM-41, and TS-1) was applied to the catalytic decomposition performance of AsH 3 . At a catalytic decomposition temperature of 100 ℃, the HZSM-5 zeolite exhibited exceptional performance, achieving a D 90% value (the duration for which the AsH 3 removal efficiency remained above 90 %) exceeding 40 h. Moreover, up to 83.1 % of the product was As 0 . Comprehensive characterization revealed that the surface of the HZSM-5 zeolite contained a large number of strong acid sites, which played a key role in As 0 generation. In situ diffuse reflectance infrared spectroscopy further revealed the activation behavior of O 2 at the Brønsted acid sites on HZSM-5. To assess its suitability in industrial applications, the AsH 3 removal performance of the HZSM-5 molecular sieve was investigated in the presence of actual gas components (CO, H 2 S, PH 3 ). This study provides new ideas for the effective catalytic decomposition of AsH 3 and the recovery of valuable products in industry.
CAS / MDL:
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Cleaner Production
·
2022
·
IF 11.072
Yibing Xie,Mengyu Wang,Xueqian Wang,Langlang Wang,Ping Ning,Yixing Ma,Jichang Lu,Rui Cao,Yu Xue
The traditional way for arsine (AsH 3 ) removal from the reducing exhaust gas by catalytic oxidation undershot the expect goal in pollutant emission control. This laboratory scale work used magnetic field to improve the chemical environment of AsH 3 catalytic oxidation over magnetic response catalyst Fe/HZSM-5. After introducing external magnetic field at a magnetic field intensity of 0.1 T, the catalytic performance of Fe/HZSM-5 for AsH 3 removal was improved by 52%, and the turnover frequency (TOF) value increased from 4.65 × 10 −3 s −1 to 5.73 × 10 −3 s −1 . The structure–activity relationship of the catalyst in the presence of magnetic field was investigated. The characterization results showed that Fe is mainly anchored onto the surface of Fe/HZSM-5 catalyst through an oxygen bridge, while a small proportion of Fe exists in the form of iron oxides . The Fe species and surface labile oxygen (O − ) in the aluminum tetrahedra are the magnetic active sites of Fe/HZSM-5, magnetic field promotes the reaction by increasing the activity of them. It was discovered that paramagnetic O − increased by 50% in the presence of magnetic field compared with that in its absence. Therefore, a magnetic-field-assisted oxygen cycling process is proposed. In terms of the stability of catalyst, formation of more amorphous oxidized arsenic after reaction in the presence of magnetic field reduced the toxicity to the strong acid sites of the catalyst, and the holding time of excellent AsH 3 removal efficiency was prolonged from 23 h to 35 h. These results provide new insights into magnetic-field-assisted zeolite catalysis.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2023
·
IF 9.8
Lin Chen,Tingting Fan,Min Yang,Dunfeng Si,Haotian Wu,Song Wu,Jian Xu,Dongmei Zhou
Microplastics weathering by various types of oxidants in the oxic environment and their interaction with environmental contaminants have drawn numerous scientific attention. However, the environmental fate of microplastics under a reducing environment has been largely unresolved. Herein, the change of physicochemical and redox properties of microplastics during the weathering under a sulfate-reducing environment and the interaction with arsenite were addressed. The sulfurization of phenol-formaldehyde resin microplastics under a sulfate-reducing environment generated smooth and porous particles with the induction of organic S species. Multiple spectroscopic results demonstrated thioether and thiophene groups formed by the substitute removal of O-containing functional groups. Moreover, the sulfurization process induced the reduction of carbonyl groups and oxidation of phenolic hydroxyl groups and resulted in the formation of semiquinone radicals. The O-containing functional groups contributed to microplastics redox property and As(III) oxidation while S-containing functional groups showed no obvious effect. The sulfurized microplastics had lower efficiency in mediating arsenite oxidation than the unsulfurized counterparts due to the decreased electron donating capacity. Producing hydrogen peroxides by electron-donating phenol groups and semiquinone radicals and the direct semiquinone radicals oxidation could mediate arsenite oxidation. The findings of this study help us understand the fate of microplastics in redox fluctuation interfaces.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子