INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2019
·
IF 3.375
Siqian Zhang,Cheng Zhang,Qiang Wang,Wha-Seung Ahn
A series of ZSM-5 catalysts were synthesized using fly ash from power plants and red mud from aluminum production in different weight ratios. The ZSM-5 was subsequently coimpregnated with Co and Mn and tested for the low-temperature selective catalytic reduction of NOx by NH3 (NH3-SCR). These catalysts were characterized by XRD, N2-adsorption isotherms, SEM, XPS, and H2-TPR. Among all the prepared catalysts, 5 wt % Co 10 wt % Mn/ZSM-5 had shown the best catalytic activity, with 98.8% conversion of NOx and 90.7% selectivity toward N2 at 150 °C. This is comparable to the performance of a similar ZSM-5 catalyst prepared using chemical reagents. The high ratio of Mn4+/(Mn4+ + Mn3+ + Mn2+) in the catalyst improved the NOx conversion, whereas the moderate redox property imparted by Co3+ led to high N2 selectivity. This catalyst also showed strong resistance against poisoning in 100 ppm SO2 and 5% H2O. This work demonstrates that effective NOx removal treatment with high N2 selectivity and sufficient stability for either cement plants or incinerators can be achieved by using a porous catalyst/support material produced from industrial solid wastes.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
·
2023
·
IF 3.8
Xudong Liu,Fengyuan Liu,Junqi Li,Yuanpei Lan,Jian Yang,Arun Murali,Chaoyi Chen,Wei Zhang
To accurately evaluate the phase effects of MnO x in Mn-Ce catalysts towards to low temperature NO x removal performance with NH 3 , MnCO 3 @CeCO 3 OH was synthesized firstly and decomposed to MnO 2 @CeO 2 , Mn 2 O 3 @CeO 2 and Mn 3 O 4 @CeO 2 with similar size and morphology, this will avoid the influence of size and morphology on the experimental results. Experimental results show that the MnO 2 @CeO 2 exhibiting the best NO conversion ratio, which achieved nearly 96.5 % at a low temperature of 150 °C, and the catalytic performance order of MnO x @CeO 2 is determined as: MnO 2 @CeO 2 > Mn 2 O 3 @CeO 2 > Mn 3 O 4 @CeO 2 below 200 °C, and MnO 2 @CeO 2 > Mn 2 O 3 @CeO 2 ≈Mn 3 O 4 @CeO 2 at range of 200 –400 °C. But the N 2 selectivity of Mn 2 O 3 @CeO 2 reaches 96 % at 100 °C which was higher than that of MnO 2 @CeO 2 and Mn 3 O 4 @CeO 2 . Characterizations including BET, XRD, SEM, H 2 -TPR, NH 3 -TPD and FTIR show that MnO 2 @CeO 2 has maximum specific surface area, a stronger redox ability, and more surface acid sites.
研究领域:
催化材料
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
INORGANIC CHEMISTRY COMMUNICATIONS
·
2025
·
IF 5.4
Jian Gao,Xinrui Dai,Zhenhua Gu,Guixian Deng,Jiangyong Yuan,Kongzhai Li
Catalysts loaded with metal oxides of M (M = Mn, Co, Ce) were synthesized by deposition precipitation method using cold rolled sludge (iron oxide as the main component) as a raw material for the selective catalytic reduction of NO x by ammonia (NH 3 -SCR). Among the various formulations, the co-supported catalyst containing 5 % Mn and 5 % Co on CRS-400 exhibited exceptional SCR performance, achieving over 90 % conversion of NO x from 80 °C to 200 °C. The addition of 5 % Mn and 5 % Co as active components resulted in an increase in the specific surface area for catalytic performance and an enhancement of the redox capacity, leading to a significant improvement in catalyst activity. The catalyst’s efficient denitration performance was attributed to the synergistic interaction between Mn, Co, and Fe oxides, resulting in a catalyst with a higher proportion of adsorbed oxygen, as well as an elevated composition of Mn 4+ and Fe 2+ species. The catalyst demonstrated excellent SCR activity at low-temperatures, indicating its potential for downstream applications in soot treatment equipment. This would achieve the dual benefits of purifying the atmosphere and disposing of solid waste.
研究领域:
环境科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
He Ma,Dashuai Li,Yingying Li,Yuanyuan Li,Changhua Wang,Xintong Zhang
While photocatalytic technology has been recognized as an effective means for removing low-concentration NOx in ambient atmosphere, it still faces the challenge of the deep oxidation in high efficiency. In many cases, the release of more toxic NO 2 byproduct appeared to be inevitable during the photocatalytic oxidation of NO. Herein we report that the atomically dispersed MnO x cocatalyst on TiO 2 (B) microspheres could significantly enhance the deep oxidation of NOx under mild photocatalytic conditions (1 mW/cm 2 UV-A light, 1 L/min flow rate). At an initial NO concentration of 0.35 ppm, ca. 67.15% of NO is oxidized on the MT-0.5 sample, which is 2.76 times higher than the pristine TiO 2 (B) sample. More importantly, the release of NO 2 is suppressed by 2.11 times. Comprehensive spectral analyses suggest that atomically dispersed MnO x effectively promotes the charge separation of photogenerated carriers in TiO 2 (B), even better than MnO x nanoparticles-loaded TiO 2 (B). EPR and in-situ FTIR analyses illustrate that atomically dispersed MnO x -loaded TiO 2 (B) sample exhibits excellent low concentration NOx abatement performance, thus providing a rational mechanism for the NO deep oxidation pathway. This study not only provides a unique approach for preparing non-noble metal atomically dispersed co-catalysts, but also affords an effective means for efficient photocatalytic NO degradation.
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
·
2022
·
IF 16.744
Bingke Xie,Dongyun Chen,Najun Li,Qingfeng Xu,Hua Li,Jianmei Lu
Nitrogen oxide (NOx) removal has long been a subject that has motivated researchers to develop a diverse range of techniques, including physical adsorption, biofiltration, low temperature plasma, selective catalytic reduction, and photocatalytic oxidation. In this work, Cs 3 Bi 2 Br 9 lead-free perovskite was synthesized via in-situ growth on a 3D flower-like g-C 3 N 4 microsphere, which uses a series of Cs 3 Bi 2 Br 9 /g-C 3 N 4 (labeled as X% CBB/CN, where X = 5, 10, 20, 30, and 50) heterojunctions for the photocatalytic removal of NOx. The efficiency of NO removal was enhanced considerably, compared with that of the pristine elements, when irradiated with a 300 W Xe lamp with the concentration of NO at the ppb level. The results of photocurrent measurements and electrochemical impedance spectroscopy are consistent with the results of the NO removal test. Electron spin resonance results verified that ⋅OH and ⋅O 2 − are formed under visible light irradiation. We report the detailed mechanism for the photocatalytic process of NO removal by CBB/CN heterojunctions and provide insights into the potential applications of lead-free perovskite-based heterostructures in the field of photocatalysis.
研究领域:
材料科学
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环境科学
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化学
✓ 已验证
产品关联
DOI
高影响因子
Materials Science and Engineering B-Advanced Functional Solid-State Materials
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2025
·
IF 4.6
Muhammad Kamran,Muhammad Sajjad,Salman Qadir,Changle Wang,Runtong Zhang,Baode Ma,Shao-Tao Bai
Crystal facet engineering is an important concept in material science but is yet to be explored direction of fabricating catalysts with improved selectivity. In this study, we prepared pure TiO 2 brookite nanorod catalysts exposed with a variation of (120), (111), and (110) active crystal domains for photocatalytic NOx (nitrogen oxides) abatement using TALH (C 6 H 18 N 2 O 8 Ti) titania precursor via a variation of sodium lactate (C 3 H 5 NaO 3 ) and urea (NH 4 CNO) addition. The different characterization such as XRD, SEM, and TEM proved the high availability of (111) crystal facet and approximate equal presence of (120), (111), and (110) crystal domains in TALH-6U-SL resulting in up to 4.9-fold higher selectivity than commercial TiO 2 -P25 as well as other brookite nanorod catalysts. TGA, FTIR, and XPS results demonstrated that compared to other catalysts, TALH-6U-SL nanorod catalyst adsorbs more water and contains more oxygen vacancies and crystal defects, thus boosting the photocatalytic selectivity for NOx conversion to NO 3 − ions.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Liyuan Duan,Guoqiang Li,Shuting Zhang,Hongyu Wang,Yongle Zhao,Yongfa Zhang
In this study, graphitized carbon nitride photocatalysts were successfully prepared by using the desulfurized waste liquid extracting salt from coking plants. The NO x removal efficiency of g-C 3 N 4 synthesized using ammonium thiocyanate (NH 4 SCN), ammonium thiosulfate ((NH 4 ) 2 S 2 O 3 ) and ammonium sulfate ((NH 4 ) 2 SO 4 ) with different mass ratios were evaluated. The results showed that due to the addition of (NH 4 ) 2 S 2 O 3 and (NH 4 ) 2 SO 4 a large amount of sulfur-containing gas was released during pyrolysis, which significantly increased the specific surface area and pore volume of the photocatalysts. The release of sulfur-containing gas also resulted in the incorporation of sulfur, and due to this doping process the band gap of the photocatalyst was widened to 2.94 eV, thus enhancing its visible light response. C vacancies were formed in the hepazine ring, which increased the electron density around the N–(C) 3 bridge bond and formed an electron trapping center, thus inhibiting the recombination of charge carriers. The photocatalysts had increased O 2 adsorption capacity and increased number of amino groups on their surface. This facilitated the rapid generation and consumption of reactive oxygen species, inhibited the accumulation of NO 2 on the surface, reduced the production of NO 2 , thus improving the NO x removal efficiency of the photocatalysts. The principle of using “waste for waste control” was achieved, and a new method for nitrogen oxide removal was provided.
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
Environmental Technology & Innovation
·
2018
·
IF 0
Jiaorong Yan,Feixiang Zhou,Ying Zhou,Xianghao Wu,Qiulian Zhu,Huayan Liu,Hanfeng Lu
The removal of NO x with low oxidation degree, low temperature, and high vapor content from small coal-fired boiler emission through selective catalytic reduction is difficult. This study investigated liquid oxidation and absorption to remove NO x systematically. Thermodynamic calculation showed that the equilibrium constants of the NO oxidation and NO x absorption reaction are high; thus, NO x treatment by liquid oxidation and absorption is feasible. Four oxidants (NaClO 2 , NaClO, H 2 O 2 , and KMnO 4 ) and four absorbents (Ca(OH) 2 , CaCO 3 , NaOH, and Na 2 CO 3 ) were used to study the reaction mechanism of the oxidation and absorption processes. Results show that NaClO 2 solution is the best oxidant, and the optimum pH value of the oxidation reaction is 5–6. The oxidation degree reaches 100% when the concentration of the NaClO 2 solution is 1.0%, and the oxidation degree can still reach approximately 50% when the concentration is 0.1%. Ca(OH) 2 slurry has the best absorption performance among the four kinds of absorbents. The NO x removal efficiency of Ca(OH) 2 slurry can reach approximately 70% when the oxidation degree is 50%. The removal efficiency is up to 80% when the oxidation degree is 100%.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
ChemistrySelect
·
2024
·Vol. 9
·期 28
·e202401039
·
IF 1.9
Xueqi Wang,Kai Li,Fei Wang,Lei Shi,Shuangyou Bao,Jiacheng Bao,Xin Sun
Graphical In this study, we prepared the thermally modified copper slag catalyst CS-CaO-900 and applied it to a pilot-scale Fenton-like denitrification system. In single-factor experiments, the effects of six factors, namely inlet NO concentration, H 2 O 2 concentration, catalyst dosage, reaction temperature, L/G ratio, and pH value, on desulfurization and denitrification were investigated. Through analysis of the experimental results, the three factors that had the greatest impact on the maximum denitrification efficiency, namely pH value, H 2 O 2 concentration, and reaction temperature, were selected. The response surface methodology was employed to investigate the significance of the three factors and optimize the parameters, and it was finally determined that the initial pH of the slurry had the greatest impact on the maximum denitrification efficiency, followed by the H 2 O 2 concentration. At the same time, the combination of initial slurry pH and reaction temperature, initial slurry pH and H 2 O 2 concentration also had a large impact on the maximum denitrification efficiency, and the combination of reaction temperature and H 2 O 2 concentration had a non-significant impact on the denitrification efficiency. And through the model optimization to get the best parameters, denitrification experiments under this parameter to achieve the maximum denitrification efficiency of 91.5 %, for further industrial application to provide reference and guidance. In this study, Response Surface Methodology (RSM) was employed to optimize the experimental factors influencing the simultaneous removal of NOx and SO 2 in a spray tower wet scrubbing experiment. Thermally modified copper slag (CS-CaO-900) was prepared by heat treating the original copper slag. The performance of CS-CaO-900 in the synchronized removal of NOx and SO 2 was then evaluated in an expanded experimental setup. Based on single-factor experimental results, the Box-Behnken design of RSM was used to optimize the reaction parameters in a two-stage sequential reactor (bubbling reactor + spray tower). NOx removal efficiency was modeled as a function of reaction temperature, pH, and H 2 O 2 concentration. Regression curves provided a visual representation of the interaction effects among these parameters on NOx removal efficiency in the thermally modified copper slag/H 2 O 2 composite slurry. This study elucidates the characteristics of each parameter under wet scrubbing conditions and provides essential data for industrial applications.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2019
·
IF 4.507
Haotian Li,Feng Liu,Shuhui Wang,Fengjia Wang,Xin Qian,Caiduan Zhang,Yongliang Ma,Lidong Wang
Based on advanced oxidation technology, a new method for the simultaneous removal of SO 2 and NO x from industrial flue gas using Na 2 S 2 O 8 /MgO was proposed. The method does not require the body structure of the wet desulfurization device is changed but adds Na 2 S 2 O 8 to the original equipment to realize simultaneous desulfurization and denitrification. After determining Cl − was additive, the effects of various reaction factors on the simultaneous removal of SO 2 and NO x were investigated, including the Cl − concentration, the initial concentration of the oxidant, the initial pH value of the solution, and the reaction temperature. According to the characterization of removal products and the types of free radicals involved in the reaction by XRD , XPS , and EPR , the reaction mechanism was elucidated. The experimental results indicated that the removal products were mainly sulfates and nitrates. The free radicals involved in the reaction were SO 4 ·− , ·OH, and Cl·, and the key free radical was Cl·.
研究领域:
环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2014
·
IF 4.058
Jiancheng Wang,Zhaoliang Peng,Ying Chen,Weiren Bao,Liping Chang,Gang Feng
Cu-SSZ-13/cordierite monolithic catalyst was prepared by in situ hydrothermal synthesis method. The physicochemical properties of the as-prepared Cu-SSZ-13/cordierite were investigated by X-ray diffraction analysis, scanning electron microscopy, transmission electron microscopy, N 2 -adsorption, inductively coupled plasma, X-ray photoelectron spectroscopy, and solid-state NMR techniques. The removal of nitrogen oxides (NO x ) from simulated diesel vehicle exhaust gas was performed using fixed-bed reactor. The effects of crystallization time and addition of HF during hydrothermal synthesis, reaction space velocity, and aging treatment of catalyst on the catalytic performances of NO x reduction reactions were investigated. The results indicate that the optimum crystallization time was 72 h. Highly crystalline structure of zeolite Cu-SSZ-13 was formed, in a close combination with a carrier, via one step hydrothermal process. Cu-SSZ-13/cordierite showed excellent DeNO x performance for selective catalytic reduction (SCR) and anti-aging properties in a simulated diesel exhaust gas under a high space velocity. At a high space velocity of 72,000 h −1 , the highest conversion and N 2 selectivity of 94% and 90%, respectively, were achieved. After the aging for 50 h at 720 °C, NO x reduction rate was still >80% in the temperature range of 350–550 °C. The larger height to diameter ratio of the same catalysts enhanced the NH 3 -SCR catalytic activity and broadened the active temperature window. The addition of HF increased the catalytic activity and anti-aging performance of the sample.
研究领域:
催化材料
·
环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2024
·
IF 3.8
Jiangxiao Qiao,Jinxin Gan,Fei Gao,Xiangsen Xu,Jiesong Tan,Yiqing Zeng,Feng Zhang,Feng Han,Zhaoxiang Zhong,Weihong Xing
Synergistic removal of nitrogen oxides (NOx) and particulate matter (PM) can be achieved using multifunctional catalytic membranes. In this work, CePO4 nanorods were loaded on the pore surfaces of SiC membranes to construct the CePO4/SiC-X catalytic membranes. The stacked nanorod structure of the CePO4 catalyst layer facilitates the diffusion of gases to the catalyst surface during reactions. Owing to the high specific surface area, rich surface acidity, and strong redox capacity, the CePO4/SiC-400 catalytic membrane exhibits the best ammonia-selective catalytic reduction (NH3–SCR) denitration activity, achieving >90% NO conversion at a temperature of 250–380 °C and negligible N2O byproduct. In addition, the CePO4/SiC-400 catalytic membrane demonstrates excellent H2O and SO2 resistance. The performance of dust filtration and simultaneous dust filtration and denitration at 250–350 °C proposed that the dust rejection efficiency reached more than 99% at various conditions, and the dust filtration process did not affect the NH3–SCR performance of the CePO4/SiC-400 catalytic membrane. From the above results, the CePO4/SiC-400 catalytic membrane presents a broad application prospect in the simultaneous dust removal and denitration of high-temperature flue gas.
研究领域:
环境科学
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催化材料
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）