Materials Research Express
·
2021
·Vol. 8
·期 4
·045509
·
IF 1.62
Ruian Wu,Jiang Jin,Kun Li,Lei Zhao,Hua Zhang
The FeaTibOx catalyst was loaded into the pores of porous ceramic using impregnation method for removing nitrogen oxides with selective catalytic reduction (SCR) technology. The catalytic performance over FeaTibOx catalyst was studied in detail. The Fe6Ti1Ox catalyst displayed more than 95% NOx conversion within the range of 280 °C–400 °C, and still maintained 97% NOx conversion when 300 ppm SO2 and 10 vol.% water vapor were introduced at the testing temperature of 300 °C. The influence factors (including filtration velocity, NH3/NO mole ratio and oxygen concentration) for NOx conversion over Fe6Ti1Ox catalyst were also studied. The suitable NH3/NO mole ratio and oxygen concentration was 0.9 and 6%, respectively. The XRD, N2-BET, H2-TPR, NH3-TPD and XPS were employed to investigate physicochemical property of the FeaTibOx catalyst. The results illustrated that Fe6Ti1Ox catalyst has hematite Fe2O3 and TiO2 structure, better redox properties and stronger surface acid.
研究领域:
环境科学
·
催化材料
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2020
·Vol. 10
·期 23
·8086-8093
·
IF 5.721
Haoxi Jiang,Debin Kong,Ying Niu,Sheng Wang
MnO2–CoOX catalysts with different Mn/Co ratios were prepared using polyvinyl pyrrolidone (PVP) as an assistant to control the morphology and exposed crystal faces of composite oxides. The physicochemical properties of the catalysts were systematically characterized and the catalytic activity of NH3-SCR and resistance to SO2/H2O were investigated. It was found that the NO conversion over Mn–Co-0.2-PVP was apparently higher compared with that over Mn–Co-X-PVP (X = 0.9, 0.8, 0.6, and 0.4). This can be interpreted in terms of exposed crystal surface (110) and enhanced adsorption of NH3/NO, and better redox performance resulting from higher Co3+/Co2+ ratio. Furthermore, different PVP and HAc additives have different H2O and SO2 resistance. Mn–Co-0.2-PVP showed good resistance to H2O and SO2 poisoning owing to having more low-temperature (∼200 °C) NO adsorption sites, which are beneficial to promote the de-NOX reaction and less affected by SO2.
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
JOURNAL OF SOLID STATE CHEMISTRY
·
2023
·
IF 3.3
Yuting Hu,Ting Cheng,Zhaozhong Jiang,Kai Qin,Han He,Chengzhu Zhu
Fe-MIL-101-NH 2 was prepared by solvothermal method with ferric nitrate and 2-Aminoterephthalic Acid (DBC-NH 2 ), and Fe-MIL-101-NH 2 as precursor was calcined to prepare α-Fe 2 O 3 catalyst. The optimum synthesis condition and the NO conversion efficiency of α-Fe 2 O 3 were systematically investigated, and its crystallinity, micro-morphology and surface acidity were characterized. The results showed that α-Fe 2 O 3 over calcination at 400 °C for 1 h had excellent catalytic activity, SO 2 tolerance, water resistance, and stability. When an initial NO concentration of 500 ppm, the gas hourly space velocity (GHSV) of 35000 h −1 , and a reaction temperature of 350 °C, the NO conversion efficiency of α-Fe 2 O 3 remained above 90 %. The crystal structure of the catalyst was α-Fe 2 O 3 which retained the original octahedral morphology of Fe-MIL-101-NH 2 and increased a lot of new pores, leading to more abundant Lewis acid sites for promoting NO conversion efficiency.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2026
·
IF 12.2
Kaiqi Zhang,Jumabubi Yishake,Yue Zhao,Hua-Yun Xiao,Chenxi Li
The reaction between SO2 and NO2 is a key atmospheric sulfate formation pathway, yet its kinetics and mechanisms remain contentious. Here, we employ an aerosol optical tweezer to probe this reaction on microdroplets at the single-particle level. Two competing mechanistic frameworks were used for data interpretation─an aqueous and an interfacial reaction model. Accounting for intraparticle NO2 depletion, the aqueous reaction model explains the data given composition-dependent reaction rate constants. However, our experiments show that chloride ions accelerate sulfate production by more than an order of magnitude compared to sulfate ions, which cannot be explained by the aqueous reaction framework. With data extracted from previous nanoparticle experiments and this work, the interfacial reaction model provides a good fit across studies, yielding an interfacial rate constant that exponentially decreases with particle pH. To further probe the effect of organics, we modified the particle composition with ionic surfactants and polyethylene glycol (PEG). The surfactants can slow down or even completely inhibit the reaction, strengthening the hypothesis that the reaction proceeds via an interfacial pathway. Yet for the water-soluble PEG, the reaction rate decreases almost linearly with its mass fraction among solutes. Finally, under atmospherically relevant conditions, a comparison of the rate constants emphasizes using the full particle size distribution to calculate sulfate formation rates. By evaluating the SO2–NO2 reaction across a wide particle size range under different frameworks, this work provides a holistic picture of this reaction, underscoring the need to resolve this critical atmospheric process for compositionally complex particles.
✓ 已验证
DOI
PubMed
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2026
·
IF 11.3
Xiangyu Zhang,Junting Qiu,Xinming Wang
Organosulfates (OSs) are key components of atmospheric secondary organic aerosols (SOAs), yet much of their ambient mass remains unexplained. This study demonstrates that dissolved SO2 reacts directly with major biogenic terpenoids (α-pinene, β-pinene, d-limonene, β-caryophyllene, and α-terpineol) in atmospheric condensed phases to form OSs without the need for traditional oxidants. Electrospray ionization mass spectrometry confirms product molecular formulas consistent with field measurements. Kinetic experiments reveal that α-pinene reacts with SO2 at a second-order rate constant of 4.0 ± 0.9 M–1 s–1 in a 50 vol % acetonitrile/water mixture, with the rate increasing nonlinearly as water content rises, reaching 12 ± 1 M–1 s–1 at 70 vol % water. pH-dependent experiments suggest that this reaction of α-pinene can occur at rates of 60–80 M–1 s–1 at pH 3–5, typical of cloud and aerosol water. This pathway could substantially contribute to OS formation and improve multiphase model predictions. Given that dissolved SO2 concentrations (∼10–3 M) far exceed those of OH, O3, or NO3 in aqueous phase, this pathway may rival or even surpass established oxidant-based sinks for terpenoids, contributing substantially to OS formation. Incorporating terpenoid + SO2 aqueous chemistry into multiphase models could thus enhance predictions of aerosol composition, particle acidity, and climate-relevant properties.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENERGY & FUELS
·
2019
·
IF 3.021
Junli Zhang,Lei Yu,Ruiquan Gong,Meiyu Li,Hongwei Ren,Erhong Duan
Acid gases, especially sulfur dioxide (SO2), released from the burning of fossil fuels, have made a great contribution to environmental pollution. However, the technologies to remove the acid gases have high operation costs and energy requirements. A kind of hydrophilic deep eutectic solvents (DESs) were synthesized and applied to solve the problem of SO2 environmental pollution. The SO2 absorption conditions were optimized including the kind of DESs, viscosity, and temperature. The hydrophilic interaction in SO2 absorption was explored. The hydrophilic property of caprolactam/tetrabutylammonium bromide DESs (TBAB/CPL) greatly reduced the gas transfer barrier, thus accreting the SO2 absorption rate by enhancing the accessibility of the active sites on DESs and SO2. The surface tension decreased with the absorption of SO2, and the minimal surface tension of TBAB/CPL was 32 mN m–1 at 303.2 K (surface entropy, 0.0395 J K–1 m–2) when the concentration of TBAB/CPL aqueous solution was 2 mol L–1. The phase-transfer process for the SO2 absorption system was determined by nuclear magnetic resonance, Fourier transform infrared spectroscopy, and Raman spectroscopy. The mechanism of the hydrophilic absorption of SO2 in TBAB/CPL DESs was also developed.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Qingping Xin,Huajian Gao,Ke An,Xiaoli Ding,Yuzhong Zhang,Kongyin Zhao
It is essential to design a stable membrane material to solve the pollution produced by SO 2 emissions. This study aims to fabricate polystyrene (PS) nanofiber membranes, which are applied for flue gas desulfurization. PS nanofiber membranes are fabricated via electrospinning with porous polypropylene (PP) membrane as the support and high hydrophobic PS as the main membrane material. The modified membranes are characterized by scanning electron microscopy, true color confocal microscopy and other analytical methods, and the effects of mixed solvent ratio and polymer concentration on the desulfurization performance and on the stability of PS nanofiber membranes are investigated. The results suggest that an optimum hydrophobicity of PS nanofiber membrane is obtained with a water contact angle of 145°, when the polymer concentration is 5 %. The average pore size of PS nanofiber membrane is 1.56 μm, and the liquid entry pressure of water (LEPw) is 0.26 bar and the roughness of membrane is 5.674 μm. The desulfurization performance of the PS nanofiber membrane is better than that of the PP membrane. The SO 2 absorption flux of the modified membranes keeps at 7.2 × 10 −4 to 7.6 × 10 −4 mol·m −2 ·s −1 during 5 h operating, and SO 2 removal efficiency is up to 50 %, which potentially makes contributions to air pollution reduction.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Chemistry
·
2019
·
IF 1.727
Han Zhitao,Gao Yu,Yang Shaolong,Dong Jingming,Pan Xinxiang,Lan Tian,Song Liguo,Yan Zhijun,Sun Deping,Ning Kaixuan
Experiments were conducted to remove NO from simulated flue gas in a rotating packed bed (RPB) reactor with NaClO2 as wet scrubbing oxidant and diesel exhaust gas as carrier gas. The effects of various operating parameters (rotational speed, solution pH, NaClO2 concentration, liquid-gas ratio, and NO and SO2 concentrations) on NO removal performance were investigated preliminarily. The results showed that with the increase of rotational speed, oxidant concentration, and liquid-gas ratio, NO removal efficiency increased obviously. NO removal efficiency increased largely with the decrease of solution pH, and a complete removal of NO could be attained at pH 4. NO concentration imposed little effect on NO removal efficiency while coexisting SO2 in exhaust gas could enhance NOx removal greatly.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2015
·
IF 3.368
Xiaole Weng,Xiaoxia Dai,Qingshan Zeng,Yue Liu,Zhongbiao Wu
Heteropoly acids (HPAs) have been effectively utilized in selective catalytic reduction (SCR) of NO to improve the NH 3 absorption capacity and alkaline/alkali metal resistance for SCR catalysts. However, despite the promise on super-acidities, their other properties that would work on SCR process are still lack of exploration. In this study, a 12-tungstaphosphoric acid (H 3 PW 12 O 40 , HPW) was selected to modify a well-reported CeO 2 catalyst. The resulted CeO 2 /HPW catalyst was subsequently utilized for SCR of NO with excess NH 3 , which revealed a significantly promoted performance in SCR reaction. DRIFT analyses showed that the unique NO 2 absorption capacity of HPW could prevent the NO 2 being further oxidized into nitrate species and the abundant Brønsted acid sites could effectively retain the NH 3 , avoiding them being over-oxidized at evaluated temperatures. The presence of NO 2 was demonstrated able to induce a so called “fast SCR” reaction over the CeO 2 /HPW catalyst, which effectively facilitated the SCR reaction. Furthermore, we have also constructed a CeO 2 @HPW catalyst, which showed an enhanced SO 2 poisoning resistance in SCR reaction.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING & TECHNOLOGY
·
2023
·Vol. 46
·期 10
·2217-2225
·
IF 2.1
Shuangshuang Lv,Xianlong Zhang,Haoyang Dong,Shi Jin,Xinyu Wang
Manganese-antimony composite oxide catalysts were prepared for use in low-temperature selective catalytic reduction of flue gas, by adopting the strategy of passivation to regulate the valence state of the active component and control catalytic activity. Activity evaluation results found that MnSb 0.36 O y delivered 80 % NO conversion in the presence of SO 2 at 200 °C, and nearly 90 % conversion at 250 °C. Doping with Sb changed the surface micromorphology, resulting in a perforated porousness layered foam with a porous structure of tens of nanometers, which was conducive to molecular mass transfer of the reaction gas. Doping with Sb regulated the valence state of the active MnO x component, which diminished catalytic oxidation of SO 2 , thus promoting catalyst stability and limiting the toxic effect of SO 2 .
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
RESEARCH ON CHEMICAL INTERMEDIATES
·
2018
·Vol. 44
·期 5
·3455-3474
·
IF 1.674
Sun Xiao,Guo Rui-tang,Li Ming-yuan,Sun Peng,Pan Wei-guo,Liu Shu-ming,Liu Jian,Liu Shuai-wei
Fe was used as the modifier to improve the performance of CeZr 2 O
x
catalyst for the selective catalytic reduction (SCR) reaction with ammonia. Experimental results revealed that proper Fe species (Fe/Ce molar ratio = 2) could effectively improve the SCR activity of CeZr 2 O
x
, along with the elevated resistance to SO 2 and H 2 O. The characterization results including BET, XRD, H 2 -TPR and NH 3 -TPD confirmed that Fe species in Fe 2 CeZr 2 O
x
catalyst could inhibit the formation of ZrO 2 crystals and lead to higher reducibility and surface acidity. In addition, more Ce 3+ and surface active oxygen species could be detected on Fe 2 CeZr 2 O
x
compared with CeZr 2 O
x
. By means of in situ DRIFT technique, it could be deduced that the SCR reaction process over Fe 2 CeZr 2 O
x
was accelerated mainly through theL–H pathway due to the advanced adsorption of NH 3 and NO
x
species, along with the promoted NO conversion to NO 2 . Therefore, the modification of CeZrO
x
catalyst by Fe had a significant stimulation effect on its low-temperature SCR performance.
研究领域:
催化化学
·
环境科学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2021
·Vol. 12
·期 1
·517-527
·
IF 3.361
Qingping Xin,Meixue Zhao,Jianping Guo,Dandan Huang,Yinan Zeng,Yuhang Zhao,Teng Zhang,Lei Zhang,Shaofei Wang,Yuzhong Zhang
Exploring a new type of smart membrane with tunable separation performance is a promising area of research. In this study, new light-responsive metal–organic framework [Co(azpy)] sheets were prepared by a facile microwave method for the first time, and were then incorporated into a polymer matrix to fabricate smart mixed matrix membranes (MMMs) applied for flue gas desulfurization and decarburization. The smart MMMs exhibited significantly elevated SO2(CO2)/N2 selectivity by 184(166)% in comparison with an unfilled polymer membrane. The light-responsive characteristic of the smart MMMs was investigated, and the permeability and selectivity of the Co(azpy) sheets-loaded smart MMMs were able to respond to external light stimuli. In particular, the selectivity of the smart MMM at the Co(azpy) content of 20% for the SO2/N2 system could be switched between 341 and 211 in situ irradiated with Vis and UV light, while the SO2 permeability switched between 58 Barrer and 36 Barrer, respectively. This switching influence was mainly ascribed to the increased SO2 adsorption capacity in the visible light condition, as verified by adsorption test. The CO2 permeability and CO2/N2 selectivity of MMMs in the humidified state could achieve 248 Barrer and 103.2, surpassing the Robeson's upper bound reported in 2019.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）