CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Yuchen Zhou,Zezhi Chen,Huijuan Gong,Xiaoshu Wang,Lu Chen,Huiqiang Yu
Zinc porphyrins, boasting a coordination environment akin to that of natural carbonic anhydrase (CA), coupled with excellent structural stability, built-in hydrophobic pocket, and suitable charge of center Zn 2+ , were considered as potential CA-mimics for CO 2 capture. To validate this assumption, three zinc porphyrin representatives, zinc porphin (ZnP), zinc protoporphyrin IX (ZnPP), and zinc meso -tetrakis(N-methylpyridinium-4-yl) porphyrin (ZnTMPyP), were prepared, and tested performance in enhancing CO 2 absorption in water and K 2 CO 3 solutions. The results from CO 2 absorption experiments indicated that ZnTMPyP with the optimal dosage increased CO 2 absorption rate by 44.25 % in water, and ZnPP with the optimal dosage increased the CO 2 absorption rate by 63.67 % in 20 wt% of K 2 CO 3 solution, which are respectively 1.53 and 2.07 times of CO 2 absorption performance of zinc cyclen (ZnC), the most effective CA-mimic reported. Besides, the zinc porphyrins demonstrated excellent stability and reusability throughout five cycles of CO 2 absorption and desorption, which are vital aspects for practical applications. Through the calorimetric method and density functional theory (DFT) calculations, it was confirmed that the prepared zinc porphyrins had similar enzymatic behavior and catalytic CO 2 hydration pathway to natural CA. According to the results of characterization and DFT calculations, high dispersion, the lowest charge of the Zn 2+ center, and the existence of additional CO 2 adsorption sites (propionate ions), endow ZnPP with the highest catalytic activity in the K 2 CO 3 solution.
研究领域:
化学
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环境科学
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生物化学
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产品关联
DOI
高影响因子
FUEL
·
2021
·
IF 6.609
Pengfei Cao,Haitao Zhao,Stephen Adegbite,Bolun Yang,Edward Lester,Tao Wu
CO 2 dry reforming of methane (DRM) is one of the most promising routes for the large-scale utilization of greenhouse gases (CO 2 and CH 4 ). However, it is still of challenges to develop catalysts that are efficient and cheap but are of high resistivity in coke formation to maintain long-term stability. Herein, K 2 CO 3 was used as a promoter to enable dynamic coke elimination reaction over the Ni/Al 2 O 3 for CO 2 reforming of CH 4 . K 2 CO 3 -modified Ni/Al 2 O 3 catalysts were synthesized via a wet co-impregnation method and investigated for DRM. The 1.0 K-Ni/Al 2 O 3 exhibited the best stability in the test of 96 h on stream at 800 °C. It was found that coke resistance of K 2 CO 3 modified catalyst was significantly improved, as the coke formation on 1.0 K-Ni/Al 2 O 3 catalyst was only 1/3 of that on Ni/Al 2 O 3 catalyst after a long-term test. Characterization results showed that the growth of Ni particles was suppressed because the addition of K 2 CO 3 enhanced the interaction between Ni and Al 2 O 3 . Meanwhile, the addition of K 2 CO 3 raises the basicity of the catalysts, which enhances the adsorption of CO 2 on the surface and subsequently facilitates CO 2 dry reforming of CH 4 . In addition, the transient experiment reveals that K 2 CO 3 enables a dynamic coke elimination reaction (KCER) via enhancing the catalytic reaction of disordered carbon with CO 2 , which is considered as a promising low-cost approach to stabilize the performance of the Ni-based catalysts in DRM reaction.
研究领域:
化学工程
·
催化材料
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产品关联
DOI
高影响因子
ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE-INTERNATIONAL JOURNAL OF RESEARCH IN PHYSICAL CHEMISTRY & CHEMICAL PHYSICS
·
2020
·Vol. 235
·期 4
·451-466
·
IF 2.03
Yuli Xue,Yan Zhang,Xiaoling Tan,Wenqing Li,Zhongshu Li,Shaonan Xu,Peng Zhang,Jian Wang,Peiping Zhang,Shiding Miao
It is of importance to reclaim single-salt of potash from Li + -type brines of low concentration. In this work the potassium salts KHCO 3 was efficiently separated from the lithium carbonate-type brines with the aid of CO 2 carbonation. The phase field was provided in which the precipitation of KHCO 3 occurs and single-salt of potassium can be obtained. The low concentration of [Li + ] was also successfully concentrated to a high level (8.1 g/L), and this concentration can be used as sources for Li + -salts production using pre-developed strategies, which looks forward wider applications of the lithium resources of natural brine. This state-of-art was traced via isotherm evaporation on the quaternary system of Li + –K + –CO 3 2− –H 2 O at 298.15 K in which the carbonation steps were performed by CO 2 . Metastable phase diagram was found to consist of three invariant points, seven univariant curves, and four crystallization fields corresponding to Li 2 CO 3 , KHCO 3 , potassium carbonate sesquihydrate (K 2 CO 3 ⋅ 3/2H 2 O), and a potassium carbonate and potassium bicarbonate double salt (K 2 CO 3 ⋅ 2 KHCO 3 ⋅ 1.5H 2 O). There was no crystallization field corresponding to LiHCO 3 . The pH-composition diagram and density-composition diagram were also plotted. This work was carried out in aim of extracting/separating single salts of alkali metals from carbonate-type brines of west China.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
Reaction Kinetics Mechanisms and Catalysis
·
2023
·Vol. 136
·期 2
·771-786
·
IF 1.8
Su Haitang,Yang Zhixiu,Xiao Guomin,Gao Lijing,Wei Ruiping,Zhang Jin
A series of cost-effective (X) K 2 CO 3 /γAl 2 O 3 catalysts for efficient conversion of vinyltrimethoxysilane (VTMOS) to vinyltris(β-methoxyethoxy)silane (VTMOEOS) were synthesized. The microstructure and active site of the synthesized catalysts were analyzed by BET, XRD, FT-IR, SEM, and CO 2 -TPD. The results showed that the synthesized catalysts formed K–O–Al strong basic sites while maintaining the original structure, which greatly improved the basic strength of the catalysts. It was found that the 60%K 2 CO 3 /γAl 2 O 3 possessed the highest the catalytic activity under the activation temperature of 600 °C by optimizing the preparation conditions of K 2 CO 3 /γAl 2 O 3 . Moreover, the optimal reaction process conditions were also determined by optimizing the experimental reaction temperature, reaction time, catalyst dosage, and reactant molar ratio under (60%, 600 °C) K 2 CO 3 /γAl 2 O 3 catalysis. Under the optimal reaction conditions, the conversion of VTMOS was 92.5% and the yield of VTMOEOS was 65%. Meanwhile, the 60%K 2 CO 3 /γAl 2 O 3 catalyst was satisfactorily reusable and maintained a high catalytic activity after four cycles of catalytic reactions.
研究领域:
材料化学
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催化化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2016
·
IF 5.31
Yafei Guo,Changhai Li,Shouxiang Lu,Chuanwen Zhao
K 2 CO 3 supported on activated carbon (K 2 CO 3 /AC) shows promise as a potential candidate for removing low-concentration CO 2 from environmental control and life support systems (ECLSS). However, K 2 CO 3 /AC would suffer a decreased CO 2 sorption capacity due to sorbent deactivation in acid impurities such as SO 2 and NO 2 . To solve this problem, water vapor pretreatment, KOH addition and polyethyleneimine (PEI) modification were proposed as efficacious means for improving its CO 2 sorption capacity and mitigating the sorbent deactivation in these acid impurities. CO 2 sorption performances of the pretreated and modified sorbents were evaluated in a fixed-bed reactor under simulated ECLSS conditions of 20 °C, 1.0% CO 2 , 2.0% H 2 O, 30 ppm SO 2 , 20 ppm NO 2 and balanced N 2 . The mechanisms for sorbent deactivation inhibition by water vapor pretreatment, KOH addition and PEI modification were revealed by N 2 adsorption-desorption, X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FT-IR). Effects of water vapor pretreatment duration, KOH addition and PEI loading on sorbent deactivation inhibition performances were demonstrated. Furthermore, the long-term working stabilities of the pretreated and modified sorbents in impurities were evaluated. The results will provide fundamental support on practical application of K 2 CO 3 /AC for low-concentration CO 2 removal in ECLSS.
研究领域:
环境控制与生命支持系统
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气体吸附
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材料化学
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空气净化技术
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二氧化碳捕集
✓ 已验证
DOI
高影响因子
Chemical Science
·
2024
·
IF 7.6
Yonghui Zhang,Xin Xu,Qingxuan Geng,Qingwei Li,Xiuli Li,Yixuan Wang,Zihuan Tang,Biao Gao,Xuming Zhang,Paul K. Chu,Kaifu Huo
Alkali activation was the common method to prepare commercial porous carbon. In a mixed alkali activation system, the role of individual alkali was generally assumed to be the same as in single alkali activation system, and only low corrosiveness of weak alkali was mostly emphasized. However, the intrinsic roles of individual alkali should be finely understanded and redefined to illuminate the activation pathway from the perspective of internal chemical reactions rather than corrosiveness. Herein, combing the in situ TG-MS analysis, DFT calculation and other characterizations, the activation processes were precisely tracked and the activation pathways were proposed. In the mixed alkali activation system, the strong alkali KOH served as the activation promoter, first decomposing into K2O, which then attacks the C-C bonds, forming active reaction sites defined as pore seeds. The weak alkali K2CO3 acted as the activation pathway modifier, CO32− preferentially etched the pore seeds over K2O due to the lower reaction barrier of CO32− interacting with the pore seeds. Consequently, the rough etching reaction of KOH was replaced and suppressed by the gentler action of CO32− forming more micropores. When the ratio of strong to weak alkali was 1:1, the obtained CK1K2-122 owned the highest microporosity (82.61%) and large specific surface area (1962.18 m2 g-1). It exhibited high specific capacitance of 296.7 F g-1 and excellent cycling stability with 98.3% retention after 10,000 cycles. The supercapacitor demonstrated high energy density of 114.4 Wh kg-1 at power density of 17.5 kW kg-1, with a broad potential window of 3.5 V.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Jinpeng Zhai,Zhenjiang Wang,Jia Ouyang,Beichen Xue,Chao Liu,Rui Xiao
Sewage sludge (SS), as a common solid waste with large production and rich organic nitrogen, has the potential to synthesize N-doped carbon (N-C) for CO 2 adsorption. In this paper, A novel synthesis method of N-C CO 2 adsorbent from SS by structural regulation of glucose (Glc) and further activating with K 2 CO 3 was proposed. Besides, the influence mechanism of N-doping form and content on CO 2 absorption capacity of N-C was studied by density functional theory calculations (DFT). Results showed that Glc had the effect of promoting the formation of internal mesoporous structure and adjusting pyrrole-N (N-5) structure into quaternary-N (N-Q) structure. The N-C prepared with feedstock mixing sludge, Glc and K 2 CO 3 powder (mass ratio of SS/Glc/K 2 CO 3 = 3:1:4) at 800 °C showed the highest CO 2 adsorption capacity (3.00 mmol/g at 25 °C and 1 bar) and superior CO 2 selectivity for CO 2 /CO/CH 4 under continuous flow. Theoretical calculations identified a nitrogen-doping threshold effect, where elevated nitrogen content strengthened pyridine-N (N-6) induction effects to enhance localized polarity for CO 2 adsorption. Conversely, lower doping levels amplify conjugation effects via N-5 prevalence, significantly improving adsorption capacity. This dual mechanism demonstrates that N-6 configurations optimize local polarity at high doping ratios, while N-5 architectures maximize electron delocalization efficiency at reduced nitrogen concentrations.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
Energy Technology
·
2018
·Vol. 6
·期 11
·2273-2281
·
IF 3.175
Peng Chen,Suhui Lu,Chao Yang,Zi He,Xuli Chen,Kunkun Guo
The molten salt activation containing different oxysalts are proposed to activate the ordered mesoporous carbons loading on graphene layers (OMC/G). The effects of different oxysalts activations on the structures of OMC/G are thoroughly investigated by scan electron microscopy (SEM), small angle X-ray scattering (SAXS), Raman spectroscopy and nitrogen adsorption-desorption at 77 K. The structures of these carboneous materials are related with the oxidizing nature of these oxysalts. By using weak oxysalt of K 2 CO 3 , the original structure of OMC/G is almost kept together with the appearance of a lot of micropores and mesopores. The electrochemical performances of OMC/G after different oxysalts activation are also studied for supercapacitor applications. OMC/G after weak oxysalt of K 2 CO 3 based electrode results in the highest specific capacitance up to 332.5 F g −1 at a current density of 1.0 A g −1 , which is higher than those after both KOH activation (276.8 F g −1 ) and the other three oxysalts activation. Moreover, OMC/G-K 2 CO 3 shows an excellent cycling stability with no capacitance loss over 5000 cycles. The molten salt activation would be potentially applied to activate the porous carbons for supercapacitor applications.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Zongze Lv,Junqiang Han,Tao Deng,Chang Gao,Jianan Li,Changlei Qin
Integrated CO 2 capture and utilization (ICCU) is an emerging technology to reduce CO 2 emissions by greatly simplifying the processes of conventional CO 2 capture and utilization. In particular, ICCU-methanation could directly convert the low-concentration CO 2 into CH 4 using hydrogen from new energy electricity, representing an efficient Power-to-Gas route. CO 2 adsorption/catalytic materials play a crucial role for the operation of ICCU-methanation, and it is more feasible to scale up material production and avoid components interference by directly combining the sorbent and catalyst. However, it is necessary to reveal the effect of different arrangements of sorbent and catalyst on reaction characteristics of ICCU-methanation. In the work, the matching of K 2 CO 3 -doped Li 4 SiO 4 sorbent with various supported Ni-based catalyst was tested and four arrangements of sorbent and catalyst particles in a fixed-bed were investigated to understand the influences on ICCU-methanation. Results show that the presence of catalyst accelerates CO 2 supply by sorbent and achieves quicker methanation, and the promotion effect becomes more obvious with a closer contact between the sorbent and catalyst. Under optimized conditions, ICCU-methanation of uniformly mixed K-Li 4 SiO 4 and Ni/Al 2 O 3 shows an excellent performance with very stable CO 2 conversion of 95.58% and CH 4 selectivity of 93.29% during cyclic reactions.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Science and Engineering B-Advanced Functional Solid-State Materials
·
2026
·
IF 4.6
Lulu Jiang,Wenqi Lei,Xiaoyun Miao,Xiulin Wang,Yongcun Liu,Yuanshuang Zheng,Xiaofeng Ye,Donglin Han
Ba 3 MoNbO 8.5 -based materials are an attractive class of hexagonal perovskite-derived oxide ion conductors, and the oxide ion conductivity can be increased to 0.012 Scm −1 at 700 °C by doping Zr to form the composition of Ba 3 MoNb 0.95 Zr 0.05 O 8.475 (BMNZ5). However, BMNZ5 shows lower relative density around 69% after sintering at 1200 °C. Increasing the temperature to 1300 °C densifies the sample but unfortunately results in the formation of a BaMoO 4 second phase. Interestingly, adding K 2 CO 3 leads to the reduced temperature forming the BMNZ5 phase, and the relative density increases to 89% by adding 5 mol% K 2 CO 3 . Although the conductivity decreases slightly, adding K 2 CO 3 leads to an acceptable balance between the relative density and conductivity. The samples added with 1.0, 2.5 and 5.0 mol% K 2 CO 3 show reasonably high total conductivity of 0.0079, 0.0062 and 0.0077 Scm −1 at 700 °C in a dry Ar-20% O 2 atmosphere. No proton conduction was detected in both the pristine and 2.5 mol% K 2 CO 3 -added compositions by the H 2 O/D 2 O isotope effect measurements.
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DOI
高影响因子
ZEITSCHRIFT FUR PHYSIKALISCHE CHEMIE-INTERNATIONAL JOURNAL OF RESEARCH IN PHYSICAL CHEMISTRY & CHEMICAL PHYSICS
·
2018
·
IF 1.144
Miao Shiding,He Shuai,Xue Yuli,Nian Hongen,Wang Jian,Zhang Peng,Zhu Fujie,Wen Wanglin
Food grade (K2CO3 wt.%>99.0%, GB/T 25588-2010) potassium carbonate (K2CO3) has been extracted from low concentration [K+] solutions of K2CO3-Na2CO3-H2O,
which refers to a subsystem of brine water in the Lop Nor Lake in West China. Procedures of the isothermal evaporation, crystallization, CO2 acidification, filtration, and calcination were employed to prepare the K2CO3. This research focuses on the phase study
of metastable equilibria between K2CO3-Na2CO3-H2O and KHCO3-NaHCO3-H2O. The solubility, density, conductivity, and pH values were determined. Phase diagrams were plotted at temperatures of 298.2 and 313.2
K. At 298.2 K the ternary system of K2CO3-Na2CO3-H2O was found to have double salts in form of solid solutions Na2CO3·K2CO3·(6–12)H2O, which would hinder the process
of getting pure K2CO3 by the means of isothermal evaporation. In this protocol the high-pressure CO2 was charged to the ternary carbonate solution, and the K2CO3-Na2CO3-H2O was moved to bicarbonate system
KHCO3-NaHCO3-H2O. This quaternary system is of a simple co-saturation type of diagram, in which a solid solution (KHCO3·NaHCO3) was found to be greatly affected by temperatures. This finding affords efficient separation of KHCO3
from the KHCO3-NaHCO3-H2O solutions.
研究领域:
无机化学
·
化学工程
·
相平衡
·
矿物加工
·
资源回收
✓ 已验证
DOI
高影响因子
THERMOCHIMICA ACTA
·
2017
·
IF 2.236
Zhongyun Zhou,Ke Wang,Zeguang Yin,Pengfei Zhao,Zhen Su,Ji Sun
Highly efficient K 2 CO 3 -doped lithium orthosilicate (Li 4 SiO 4 ) sorbents were synthesized using acid treatment to overcome the typical kinetic limitations of sorbents at low CO 2 concentrations. The effects of K 2 CO 3 on the structure and absorption properties were characterized using various morphological characterization techniques, differential scanning calorimetry (DSC) and thermogravimetric analysis (dynamic and isothermal). The results showed that different amounts of K 2 CO 3 greatly affected the physical-chemical properties and absorption kinetics of the sorbents. On one hand, K 2 CO 3 formed a solid solution with Li 4 SiO 4 and generated favorable characteristics (a smaller crystal size, corrugated morphology, larger surface area and higher surface concentration of Li 2 O), significantly facilitating the chemisorption processes. On the other hand, a higher amount of doped K 2 CO 3 was located on the surface, which induced molten phases during CO 2 absorption, remarkably decreasing the diffusion processes. Therefore, 0.1 M K 2 CO 3 doped sorbent obtained noticeable absorption capacity and good regenerability in 15 vol.% CO 2 .
研究领域:
材料科学
·
环境化学
·
能源工程
·
无机化学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）