PROCEEDINGS OF THE COMBUSTION INSTITUTE
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2022
·
IF 6.535
Xing Yuan,Chaohe Zheng,Zuwei Xu,Qinghua Yang,Tiantian Zhang,Xi Luo,Haibo Zhao
Photothermocatalytic oxidation is an environmentally-friendly, low-temperature, and high-efficient method to remove the air pollutant. Yet, the lack of active, inexpensive, and superior stability catalysts has greatly limited its extensive utilization. In this work, the effect of single-atom Pt loading on TiO 2 support has been theoretically and experimentally studied to improve photothermocatalytic performance for the toluene combustion through flame spray pyrolysis (FSP). Pt loading can play two crucial roles into TiO 2 optimization: (1) The low-valence Pt cation incorporated into TiO 2 lattice is dramatically responsible for the anatase-rutile transformation (ART) and formation of sufficient oxygen vacancies ; (2) Introducing the defect energy level and Pt-3d orbitals remarkably promote the charge separation efficiency of single-atom catalysts. Moreover, the existence of single-atom Pt nanoparticles can signally boost the activity of surface adsorbed and lattice oxygen, as well as substantially reduce the oxygen vacancy formation energy. Thus, the toluene removal under light irradiation reaches 90% conversion below 160 °C and is maximally 18 °C lower than that under only thermocatalytic oxidation. It is attributed to larger specific surface area (SSA), outstanding low-temperature reducibility, extremely dispersed hybrid PtO x , more surface active oxygen, and higher mobility of bulk oxygen. Interestingly, when the oxygen-fuel equivalent ratio φ distinctly increases by shifting precursor solvent from xylene to ethanol, the photothermocatalytic property of toluene can be remarkably enhanced on single-atom Pt catalysts. It is due to the higher Pt dispersion resulting from more intense burning and drastic turbulent mixing, as well as the superior ratio of the metallic Pt active sites originating from higher flame temperature. Eventually, the rate-determining step of C 7 H 8 combustion on Pt/TiO 2 and Cu/TiO 2 slab are all the C C bond fracture of maleic anhydride to form acetic anhydride species, with the energy barriers of 112.03 and 188.74 kJ/mol, respectively.
研究领域:
环境科学
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催化化学
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DOI
高影响因子
Nanomaterials
·
2020
·Vol. 10
·期 9
·1795
·
IF 4.324
Junping Ding,Huanchun Wang,Yidong Luo,Yushuai Xu,Jinsheng Liu,Ruichu Lin,Yuchen Gao,Yuanhua Lin
In work, (002) oriented flower-like Bi2O2CO3(BOC) composites are synthesized by a facile chemical route and carbon quantum dots (CQDs) are modified on their surfaces through a hydrothermal method. The synthesized samples (CQD/BOC) are characterized by X-ray diffraction (XRD), SEM, X-ray photoelectron spectroscopy (XPS), UV-Vis diffuser reflectances (DRS), BET and TEM/HRTEM. The morphologies of CQD/BOC composites are the flower-like shapes, the irregular flaky structures and the fine spherical particles of CQDs attached. Photocatalytic performances were investigated in terms of removing gaseous toluene at a concentration of 94.3ppm in air, with the assistance of CQD/BOC under artificial irradiation. Our results show that CQDs modified (002) oriented Bi2O2CO3exhibits good photocatalytic activity for toluene decomposition, which can be attributed to the enhanced efficient charge separation. A certain ratio composite photocatalyst (BOC-CQD-15) shows a toluene removal rate of 96.62% in three hours, as well as great stability. CO2was verified to be the primary product. The oriented flower-like Bi2O2CO3with carbon quantum dots on the surface shows great potential in the field of solar driven air purification.Keywords:Bi2O2CO3;carbon quantum dots (CQDs);crystal orientation;toluene removal;photocatalysis
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry A
·
2015
·Vol. 3
·期 10
·5556-5562
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IF 7.443
Chunyu Chen,Qinming Wu,Fang Chen,Ling Zhang,Shuxiang Pan,Chaoqun Bian,Xiaoming Zheng,Xiangju Meng,Feng-Shou Xiao
The removal of volatile organic compounds is an important aspect of sustainability and environmental protection. Catalytic oxidation is one of the most efficient routes to achieve this. The K+ form of an aluminium-rich Beta zeolite-supported Pt nanoparticle (2.2 nm) [Pt/KBeta-seed-directed synthesis (SDS)] catalyst is very active for the low-temperature catalytic removal of toluene and results in full conversion at a much lower temperature than a conventional KBeta-supported Pt nanoparticle (Pt/KBeta-TEA) catalyst. The higher activity of the Pt/KBeta-SDS catalyst compared with the Pt/KBeta-TEA catalyst is related to the advantages of the higher K+ content and fewer terminal silanol defects in the KBeta-SDS catalyst than in the KBeta-TEA catalyst. The higher K+ content is helpful for the formation of more Pt0 species, and both the higher K+ content and the lower number of terminal silanol defects are favourable for the adsorption of toluene, as evidenced by XPS and the toluene-TPD profiles. More importantly, the Pt/KBeta-SDS catalyst shows very stable activities in the presence of H2O and CO2 in the feed gases. The combination of this extraordinary activity and excellent stability in the catalytic removal of toluene over the Pt/KBeta-SDS catalyst are important for future environment protection.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Low-Carbon Technologies
·
2024
·
IF 2.4
Lv Haorui,Leng Haihan,Li Bohan,Wang Qianyu,Ma Ximan,Zhou Runxuan,Yue Xiaoju,Wu Guodong
The escalating threat of pollutants, particularly aromatic hydrocarbons like benzene, toluene, ethylbenzene and xylene (BTEX), in aquatic environments necessitates effective remediation strategies. This study explores the potential of biochar derived from common reed (Phragmites australis) as a sustainable and multifaceted tool for the removal of toluene, a representative BTEX compound, from aqueous solutions. By harnessing reed straw as the precursor material for biochar production, this research showcases an environmentally friendly alternative to conventional disposal methods, such as incineration, offering the dual benefit of pollutant removal and carbon emissions reduction. The influence of pyrolysis temperature on biochar properties and its adsorption efficiency for toluene were rigorously examined, revealing a direct correlation between temperature and biochar’s pollutant sequestration capabilities. Results indicate that higher pyrolysis temperatures led to biochar (RB-750) with superior specific surface area (68.07 m2/g) and enhanced adsorption capabilities, demonstrating its potential as a powerful adsorbent in water treatment. The scanning electron microscope analysis revealed a complex, porous structure rich in active sites, validating the biochar’s suitability for pollutant adsorption. Optimal dosage was determined at 8 g/l, achieving an impressive toluene removal efficiency of 98.1%. Additionally, pH and initial toluene concentration significantly influenced removal efficiency. This study underscores the multifaceted potential of reed straw-derived biochar in combating water pollution while concurrently contributing to carbon emissions reduction through sustainable utilization of abundant wetland resources. Further research should delve into the impact of real-world conditions on its effectiveness, promising innovative solutions for environmental remediation efforts with a reduced carbon footprint.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Juntao Tang,Mengying Fu,Yidan Mao,Shuyi Yang,Wei Lin,Yan Yu,Shuang Song
Photocatalysis is regarded as a promising in situ air purification technology for the removal of volatile organic compounds. However, the deactivation of photocatalysts remains a serious issue that needs to be addressed. Herein, we report a novel dual-functional photocatalyst (TiO 2 @HYZ) with spatially separated catalytic sites and adsorption sites, which has been obtained by combining hydrophilic {0 0 1} TiO 2 nanosheets with hydrophobic NaY zeolite. TiO 2 @HYZ showed excellent photocatalytic activity for the degradation of gaseous toluene under UV irradiation in humid air. The optimized TiO 2 @HYZ-2 (containing 45.7 wt% TiO 2 ) achieved 96.6% toluene removal and 87.4% mineralization within 120 min. The specific reaction rate constant of TiO 2 @HYZ-2, pristine TiO 2 and P25 normalized by the unit amount of TiO 2 during the photocatalytic degradation process were calculated to be 0.481, 0.230 and 0.250 min −1 g −1 , respectively. Moreover, TiO 2 @HYZ-2 showed superior durability, maintaining stable performance over repeated toluene degradation processes, even at high toluene concentration, whereas pristine TiO 2 incurred severe deactivation with increasing number of photocatalysis cycles. The significantly enhanced activity and anti-deactivation property was attributed to a synergistic effect between HYZ and TiO 2 in the catalyst structure, which strengthened the adsorption of toluene on HYZ and facilitated effective separation of photoexcited charge carriers on TiO 2 , thus avoiding the deposition of degradation intermediates on the active sites and simultaneously improving mineralization. This work provided a new perspective for the design of efficient and deactivation-resistant photocatalysts for air pollution remediation.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2023
·
IF 7.7
Haofei Ma,Ziqi Wang,Peng Yuan,Boxiong Shen,Jie Xu
Since the yield of titanium-bearing blast furnace slag (TF) during the smelting of vanadium titanium magnetite is large, it is urgent to find ways to recycle it and implement its value-added utilization. In this study, a perovskite-rich photocatalyst was prepared by acid-washing of TF, and then Ce was doped to modify it for photocatalytic removal of gaseous toluene under the irradiation of visible light. XRD, XRF and XPS analyses demonstrated that the perovskite phase was enriched after the acid-washing, and the content of CaTiO 3 in the acid-washed slag (AS) also increased after Ce doping. The combined N 2 adsorption-desorption, UV Vis DRS, EIS, PL , and ESR analysis results indicated that the photocatalytic performance of the mentioned photocatalyst was related to the Ce dopant content. The AS doped with 20% Ce (20% Ce-AS) had a lower band gap and larger specific surface area than the others catalysts. Under visible light radiation , more active radicals were produced, and the removal efficiency of toluene reached 92.08% for 20% Ce-AS. In addition, the results of the in situ DRIFTS tests indicated that toluene was gradually degraded by the Ce-doped perovskite-type photocatalyst to alcohols and aldehydes and mineralized to H 2 O and CO 2 . This study is expected to provide a new approach for the technical development of the value-added utilization of TF coupled with the efficient removal of toluene.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 47
·期 21
·10397-10408
·
IF 3.3
Ning Gao,Xuanyu Gu,Jining Liu,Mengjie Fan,Yingwen Chen
At present, it is challenging to improve the activity and humidity resistance of ozone catalysts. Herein, an integrated MnOx–Al2O3 aerogel was prepared by a sol–gel method in this study, and its application in catalytic ozonation of toluene was explored preliminarily. Compared with the MnOx–SiO2 aerogel and impregnation catalysts (MnOx–silicalite-1 and MnOx–γ-Al2O3), the MnOx–Al2O3 aerogel exhibited superior performance in toluene removal and enhanced ozone utilization efficiency under optimal conditions (room temperature, O3 : C7H8 = 14 : 1, GHSV = 45 000 h−1 and 120 ppm C7H8). After reacting for 360 min, the 5 wt% MnOx–Al2O3 aerogel still showed stable catalytic ability, with the efficiency of toluene removal and ozone degradation maintained at 64.1% and 62.7%, respectively. Based on SEM characterization, the MnOx–Al2O3 aerogel demonstrated low MnOx agglomeration. From XPS and NH3-TPD analyses, it was found that the catalyst had a high content of Mn3+/Mn, Oβ/O, oxygen vacancies and acid sites, which was positively related to ozone degradation. Among them, an increase in the number of weak acid and moderately strong acid sites could prolong the life of active oxygen, which was the key to promoting the deep oxidation of toluene effectively. In addition, the MnOx–Al2O3 aerogel exhibited remarkable load-adjustability and humidity resistance. Therefore, the development of aerogel catalysts for catalytic ozonation of toluene is an effective strategy to alleviate the current ozone catalyst problem.
研究领域:
环境科学
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催化材料
✓ 已验证
DOI
高影响因子
POLYMER
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2025
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IF 4.5
Yong-Gang Zhao,Yu-Fei Sun,He-Gang Gao,Li-Hui Chen,Wei-Si Su,Chao Lei,Ming-Li Ye,Yin Lu
Carbon skeleton nano microspheres are regarded as a prospective adsorbent material for the removal of pollutants in water, largely due to their exceptional characteristics. In this study, different carbon skeleton microspheres were prepared using the acetonitrile precipitation method. The particle size of the microspheres was adjusted to between 80 and 100 nm by controlling the dosage of modified monomers during the reaction process and the acidity and alkalinity of the solution. The resulting material was a carboxylated nano carbon skeleton microsphere (NCS). Subsequently, the grafting of octadecylamine (C18) onto the NSC material resulted in the formation of nano carbon skeleton materials with superhydrophobic properties. The adsorption performance of the composite C18-NCS on toluene was investigated, and the effect of C18 dosage on the adsorption performance of C18-NCS was further examined. The findings revealed that the maximum adsorption of toluene by C18-NCS was 509.43 mg/g, and the adsorption process exhibited conformity to the Langmuir model and pseudo-second order kinetics. Furthermore, the adsorption behavior of the composites towards other benzenes (benzene, paraxylene) was also investigated. The thermodynamic studies demonstrated that the adsorption of benzenes on the composites was a spontaneous, heat-absorbing process. Ultimately, following three cycles, the composite exhibited a retention of over 80 % of its initial adsorption performance. In conclusion, the superhydrophobicity and thermal stabilization of C18-NCS render it an excellent and environmentally friendly adsorbent material for the efficient and rapid removal of benzene .
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2022
·Vol. 152
·期 12
·3795-3806
·
IF 2.936
Tao Wanyi,Bo Longli,Li Mingxin,Liu Jiadong
The modification of cordierite honeycomb (CH) carrier is conducive to improve the catalytic activity of catalyst that applying in the treatment of real VOCs waste gas. A honeycombed calcium aluminum silicate hydrate (C–A–S–H) thin layer was self-assembled successfully by alkaline corrosion with supersaturated Ca(OH) 2 and contacted robustly onto the CH surface (named as CHC) by chemical bond. CuMnCeO x /CHC catalyst was prepared and applied in microwave catalytic combustion of toluene to check the catalytic activity in this work. Compared with CuMnCeO x /CH catalyst, CuMnCeO x /CHC catalyst exhibited a higher catalytic capacity and the removal rate of toluene reached 99%, which was higher than 75% of CuMnCeO x /CH catalyst under same reaction conditions of toluene initial concentration 1000 mg m −3 , air flow 0.12 m 3 h −1 and bed temperature 200 °C. Based on SEM, BET, XRD, XPS, UV-Raman, H 2 -TPR and NH 3 -TPD characterizations, it showed clearly that honeycombed C–A–S–H thin layer made CuMnCeO x active particles with smaller size more uniformly embedded into the pores of itself to hinder effectively the agglomeration of active particles in reaction. The valence reversible conversion of Cu + /Cu 2+ , Mn 2+ /Mn 3+ /Mn 4+ and Ce 3+ /Ce 4+ and total valence increase of CuMnCeO x produced abundant oxygen vacancies on the catalyst surface and simultaneously improved the transformation of surface adsorbed oxygen (O ads ) to lattice oxygen (O latt ). Toluene was oxidized completely by O ads and O latt species onto the active sites and “hot spots” under microwave irradiation that following both L–H mechanism and MvK mechanism. The research work lays down a theoretical basis for the preparation of highly effective catalyst and further application in the treatment of industrial VOCs waste gas. Graphical Abstract
研究领域:
环境科学
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
Microfluidics and Nanofluidics
·
2018
·Vol. 22
·期 12
·1-13
·
IF 2.384
Lian Zheng,Ren Yong,He Jun,Chen George Z.,Koh Kai Seng
In this paper, pristine and two types of porous polydimethylsiloxane (PDMS) microparticles were fabricated using oil-in-water (O/W) single emulsion template by the needle-based microfluidic multiphase system. By manipulating the flow rate of either the dispersed or continuous phase, microparticles of various sizes were obtained. The capillary number of the continuous phase for all flow conditions applied in this study was less than 0.1, suggesting that the flow regime was dripping. The coefficients of variation (CV) of sizes under different flow conditions were less than 1.5% which indicates the particles to be highly monodispersed. The surface morphology and particle size were characterized by optical microscope and scanning electron microscope. Pristine PDMS microparticles (PDMS-P) and PDMS microparticles templated from tetrachloromethane (CCl 4 ) and white granulated sugars (PDMS-C and PDMS-S, respectively) were prepared under the same flow conditions. Subsequently, the microparticles were adopted for treatment of a synthetic wastewater that contained organic compounds such as toluene under static and dynamic states for comparison. The effects including the releasing amount, size of particles, porosity of microparticles and initial concentration of pollutants were investigated based on the toluene concentration variation, which was quantified by a gas chromatograph-headspace sampler (GC-HS). It has been found that 50 mg of porous PDMS microparticles are capable of realising over 65% of toluene removal efficiency of 200 ppm toluene aqueous solution within 2 h. The microparticles were collected and reused 30 times with unchanged treatment capacity.
研究领域:
环境科学
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材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMOSPHERE
·
2021
·
IF 7.086
Yue Lang,Yanan Yu,Hongtao Zou,Jiexu Ye,Shihan Zhang,Jianmeng Chen
Chemical park is regarded as a major contributor of VOCs emissions in China. Currently, a green and safe technology, microbial fuel cells (MFCs), is being developed for the VOCs abatement. Noting that effective electron transfer is critical to the MFC performance. In this work, flavin mononucleotide (FMN) was dosed as an electron shuttle to improve the removal of the typical toxic VOCs, toluene. The experimental results revealed that the performance of toluene removal and power generation were accelerated with the dosage of 0.2–2 μM FMN. With the addition of 1 μM FMN, the removal efficiency, the maximum output voltage and the coulombic efficiency of MFC were increased by 18.4%, 64.4% and 56.3%, respectively. However, a further increase in FMN concentration to 2 μM caused a reduction in the removal efficiency and coulombic efficiency. The images of scanning electron microscopy and confocal laser scanning microscopy showed that the presence of FMN greatly promoted the microbial growth and its activity. Furthermore, microbial community analysis also implied that the moderate dosage of FMN (0.2–1 μM) was beneficial for the growth of the typical exoelectrogens, Geobacter sp., and thus the coulombic efficiency was increased. In addition, an electron transfer pathway involving in cytochrome b , OMCs, cytochrome c , and MtrA was proposed based on the cyclic voltammetry analysis. This work will provide a fundamental theoretical support for its application of toxic VOCs abatement from the chemical park.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2021
·
IF 6.901
Juping You,Han Chen,Liangliang Xu,Jingkai Zhao,Jiexu Ye,Shihan Zhang,Jianmeng Chen,Zhuowei Cheng
Microbial fuel cell (MFC) is an innovative technology to stimulate the anaerobic degradation of hydrocarbons and recover their chemical energy. Typically, for the hydrocarbon oxidation, its performance depends upon the activity of the bioanode. In this work, four anodic potentials pertained to the redox of four different membrane proteins of the microbes, namely -0.52, -0.35, -0.16, and 0.17 V vs. Ag/AgCl, were applied to tune the bioanode. Experimental results revealed that, the more negative the bioanode potential was, the more obvious the enhancement became. The biofilm tuned at -0.35 V exhibited a highest toluene removal efficiency of 99% (800 mg/m 3 ), and a maximum power density of 8.97 mW/m 2 with the Coulomb efficiency of 2.06%. The microbial community analysis indicated that the dominant microbes in the bioanode were Comamonas sp., Petrimonas sp., Sedimentibacter sp., Ignavibacterium sp. and Parachlamydia sp., which was almost unaffected by the applied anodic potentials. The cyclic voltammetry analysis showed that the bioanode tuned at 0.17, -0.16 and -0.35 V exhibited three completely different electron transfer pathways. Furthermore, three metabolic pathways with o -cresol as an intermediate were proposed under the four applied anodic potentials. These results demonstrated that the anodic potential acclimation offers an effective enhancement method for the gaseous toluene removal combined with power generation.
研究领域:
环境科学
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微生物学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）