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Effect of K_(2)CO_(3) doping on CO_(2) sorption performance of silicate lithium-based sorbent prepared from citric acid treated sediment

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Chinese Journal of Chemical Engineering 2022年第11期51卷 10-20页

作者： Junya Wang Kai Chen Yi Wang Jiuming Lei Abdullah Alsubaie Ping Ning Shikun Wen Taiping Zhang Abdulraheem S.AAlmalki AAlhadhrami Zhiping Lin Hassan Algadi Zhanhu Guo Faculty of Environmental Science and Engineering Kunming University of Science and TechnologyKunming 650500China Ecological Environment Monitoring Station Linxiang BranchLincang Municipal Bureau of Ecology and EnvironmentLincang 677000China Department of Physics College of KhurmaTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Chemistry Faculty of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Integrated Composites Laboratory(ICL) Department of Chemical and Bimolecular EngineeringUniversity of TennesseeKnoxvilleTN 37996United States Department of Electrical Engineering Faculty of EngineeringNajran UniversityP.O.Box 1988Najran 11001Saudi Arabia College of Materials Science and Engineering Taizhou UniversityTaizhou 318000China

In this paper,a low-cost and environmental-friendly leaching agent citric acid(C_(6)H_(8)O_(7))was used to treat the sediment of Dianchi Lake(SDL)to synthesize lithium silicate(Li_(4)SiO_(4))based CO_(2)sorbent.The results were compared with that treated with strong acid.Moreover,the effects of preparation conditions,sorption conditions and desorption conditions on the CO_(2)sorption performance of prepared Li_(4)SiO_(4)were systematically studied.Under optimal conditions,the Li_(4)SiO_(4)sorbent was successfully synthesized and its CO_(2)sorption capacity reached 31.37%(mass),which is much higher than that synthesized from SDL treated with strong acid.It is speculated that the presence of some elements after C_(6)H_(8)O_(7)treatment may promote the sorption of synthetic Li_(4)SiO_(4)to CO_(2).In addition,after doping with K_(2)CO_(3),the CO_(2)uptake increases from the original 12.02%and 22.12%to 23.96%and 32.41%(mass)under the 20%and 50%CO_(2)partial pressure,respectively.More importantly,after doping K_(2)CO_(3),the synthesized Li_(4)SiO_(4)has a high cyclic stability under the low CO_(2)partial pressure.

关键词： CO_(2)sorbents Li_(4)SiO_(4) Sediment citric acid Doped with K_(2)CO_(3)

Preparation and Performance of Chitosan/citric acid Modified Magnesium Oxychloride Cement

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Journal of Wuhan University of Technology(Materials Science) 2023年第6期38卷 1326-1334页

作者： SONG Zijian LIU Lang YU Peipei ZHANG Yunsheng LI Xincheng CHU Hongqiang JIANG Linhua College of Mechanics and Materials Hohai UniversityNanjing 2100China School of Civil Engineering Lanzhou University of TechnologyLanzhou 730050China Yunnan Institute of Building Research Co. LtdKunming 650223China

citric acid(CA)and chitosan(CS)were employed to modify magnesium oxychloride cement(MOC).Multiscale measurements were implemented to study the properties of the modified MOC pastes.Results show that the addition of CA/CS significantly changes the content of each phase and the microstructure of phase 5.The single addition of CA can effectively increase the compressive strength of MOC after 7 d curing,while CS exerts no obvious effect on the compressive strength.As to the simultaneous addition of CA and CS,the compressive strength of MOC gradually decreases with the increasing content of CS.Interestingly,mixing CA and CS significantly enhances the water resistance of MOC and decreases the degradation rate of MOC in phosphate buffered solution,which can be ascribed to the low specific surface area of the plate-like crystals in the modified MOC and the reduction of pores in the structure.

关键词： magnesium oxychloride cement modifier citric acid chitosan

MUF Resins Improved by citric acid as Adhesives for Wood Veneer Panels

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Journal of Renewable Materials 2023年第2期11卷 539-553页

作者： Claudio Del Menezzi Antonio Pizzi Siham Amirou Xuedong Xi Department of Forestry Engineering Faculty of TechnologyUniversity of BrasiliaBrasíliaBrazil LERMAB University of LorraineNancyFrance SeniorPost-Doctoral Internship LERMAB-ENSTIBUniversity of LorraineEpinalFrance Yunnan Key Laboratory of Wood Adhesives and Glue Products College of Material Science and EngineeringSouthwest Forestry UniversityKunmingChina International Joint Research Center for Biomass Materials Southwest Forestry UniversityKunmingChina

This article presents the first applied results of using citric acid in combinations with a melamine-urea-formal-dehyde(MUF)resin for bonding wood veneers.The chemical reactions involved are shown based on a MALDI ToF analysis of the reaction of the MUF resin with citric acid.The preliminary results of the physical and mechanical properties of the LVL prepared are also presented.Veneers from Populus sp were used to manufacture 5-layer laminated veneer lumber(LVL)of small dimensions.Five combinations of the amount of citric acid,MUF spread rate and pressing parameters were tested.LVL bonded with 20%of citric acid+100 g/m^(2)of MUF,hot-pressed using a 3-step process with maximum 1.5 MPa of pressure yielded the board with better dimensional stability and mechanical properties.It could be concluded that citric acid in combination with MUF can be used for bonding wood veneer and the research should be continued to study further the parameters involved and to enhance the results.

关键词： LVL wood adhesives citric acid MUF resins MALDI ToF mechanical performance

Urchin-like Na-doped zinc oxide nanoneedles for low-concentration and exclusive VOC detections

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Journal of Advanced Ceramics 2024年第4期13卷 507-517页

作者： Yiwen Zhou Yifan Luo Zichen Zheng Kewei Liu Xiaoxi He Kaidi Wu Marc Debliquy Chao Zhang College of Mechanical Engineering Yangzhou UniversityYangzhou 225127China Material Science Department University of MonsMons 7000Belgium

In the early-stage diagnosis of lung cancer,the low-concentration(<5 ppm)volatile organic compounds(VOCs)are extensively identified to be the biomarkers for breath analysis.Herein,the urchin-like sodium(Na)-doped zinc... 详细信息

In the early-stage diagnosis of lung cancer,the low-concentration(citric acid.The Na-doped ZnO gas sensor with a 3:1 molar ratio of Na^(+)and citric acid showed outstanding sensing properties with an optimal selectivity to various VOCs(formaldehyde(HCOH),isopropanol,acetone,and ammonia)based on working temperature regulation.Specifically,significantly enhanced sensitivity(21.3@5 ppm)compared with pristine ZnO(~7-fold),low limit of detection(LOD)(298 ppb),robust humidity resistance,and long-term stability of formaldehyde sensing performances were obtained,which can be attributed to the formation of a higher concentration of oxygen vacancies(20.98%)and the active electron transitions.Furthermore,the improved sensing mechanism was demonstrated by the exquisite band structure and introduction of the additional acceptor level,which resulted in the narrowed bandgap of ZnO.

关键词： zinc oxide(ZnO) heterovalent ions doping citric acid gas sensor volatile organic compound(VOC)detection lungcancer

Recovery of Li, Ni, Co and Mn from spent lithium-ion batteries assisted by organic acids: Process optimization and leaching mechanism

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 518-530页

作者： Liuyi Ren Bo Liu Shenxu Bao Wei Ding Yimin Zhang Xiaochuan Hou Chao Lin Bo Chen School of Resources and Environmental Engineering Wuhan University of TechnologyWuhan 430070China State Environmental Protection Key Laboratory of Mineral Metallurgical Resources Utilization and Pollution Control Wuhan University of Science and TechnologyWuhan 430081China Zhejiang New Era Zhongneng Recycling Technology Co. LtdShaoxing 312000China Shenzhen Water Planning&Design Institute Co. LtdShenzhen 518000China

The proper recycling of spent lithium-ion batteries(LIBs)can promote the recovery and utilization of valuable resources,while also negative environmental effects resulting from the presence of toxic and hazardous substances.In this study,a new environmentally friendly hydro-metallurgical process was proposed for leaching lithium(Li),nickel(Ni),cobalt(Co),and manganese(Mn)from spent LIBs using sulfuric acid with citric acid as a reductant.The effects of the concentration of sulfuric acid,the leaching temperature,the leaching time,the solid-liquid ratio,and the reducing agent dosage on the leaching behavior of the above elements were investigated.Key parameters were optimized using response surface methodology(RSM)to maximize the recovery of metals from spent LIBs.The maxim-um recovery efficiencies of Li,Ni,Co,and Mn can reach 99.08%,98.76%,98.33%,and 97.63%.under the optimized conditions(the sulfuric acid concentration was 1.16 mol/L,the citric acid dosage was 15wt%,the solid-liquid ratio was 40 g/L,and the temperature was 83℃ for 120 min),respectively.It was found that in the collaborative leaching process of sulfuric acid and citric acid,the citric acid initially provided strong reducing CO_(2)^(-),and the transition metal ions in the high state underwent a reduction reaction to produce transition metal ions in the low state.Additionally,citric acid can also act as a proton donor and chelate with lower-priced transition metal ions,thus speeding up the dissolution process.

关键词： spent lithium-ion batteries leaching response surface methodology sulfuric acid citric acid

Adsorption of trichlorphon on phyllosilicate minerals:Effect of low-molecular-weight organic acids

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Pedosphere 2024年第1期34卷 78-87页

作者： Hongfeng CHEN Zhouyang HE Mingxia HOU Cilai TANG Yonghong WU College of Hydraulic&Environmental Engineering China Three Gorges UniversityYichang 443002China Hubei Field Observation and Scientific Research Stations for Water Ecosystem in Three Gorges Reservoir China Three Gorges UniversityYichang 443002China Engineering Research Center of Eco-Environment in Three Gorges Reservoir Region China Three Gorges UniversityYichang 443002China State Key Laboratory of Soi and Sustainable Agriculture Institute of Soil SciencesChinese Academy of SciencesNanjing 210008China

The use of trichlorphon in large quantities causes a large number of organic pollutants to enter water, sediments, and soils. Phyllosilicate minerals are considered effective adsorbents for organic pollutants. However, the adsorption behavior of organic pollutants on soil minerals affected by low-molecular-weight organic acids(LMWOAs) is not fully understood. In this study, the effect of LMWOAs on the adsorption behavior of trichlorphon on phyllosilicate minerals was investigated using a combination of adsorption measurements and molecular spectroscopic techniques(attenuated total reflection-Fourier transform infrared spectroscopy(ATR-FTIR) and X-ray photoelectron spectroscopy(XPS)). The adsorption of trichlorphon onto kaolinite(KAO) and montmorillonite(MON) was suppressed by increasing pH, indicating that electrostatic interaction played a key role in adsorption, especially at low pH. In the presence of citric acid(CA), there was an obvious promotion of trichlorphon adsorption on KAO and MON. In the presence of oxalic acid(OA), the adsorption of trichlorphon on KAO was promoted, whereas the adsorption on MON was inhibited, especially at pH 4.0. The presence of CA and OA increased the adsorption by increasing the exposure of hydrophobic sites of KAO and MON. The results from ATR-FTIR and XPS also indicated that the hydrophobic Si–O sites of phyllosilicate minerals were the preferred adsorption sites for trichlorphon in the presence of CA and OA, probably driven by the hydrophobic effect. However, the weak effect of OA on MON caused an increase in the electrostatic repulsion between MON and trichlorphon molecules, thus inhibiting adsorption. This study is significant for a deeper understanding of self-purification of soil and sediment systems in the presence of organic pollutants.

关键词： adsorption behavior citric acid hydrophobic effect organic pesticide organic pollutant organochlorine oxalic acid

Catalytic activity of porous manganese oxides for benzene oxidation improved via citric acid solution combustion synthesis

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Journal of Environmental Sciences 2020年第12期32卷 196-204页

作者： Hao Guo Zhixiang Zhang Zhi Jiang Mingxia Chen Hisahiro Einaga Wenfeng Shangguan Research Center for Combustion and Environmental Technology Shanghai Jiao Tong UniversityShanghai 200240China Department of Energy and Material Sciences Faculty of Engineering SciencesKyushu UniversityFukuoka 816-8580Japan

Various manganese oxides(MnOx) prepared via citric acid solution combustion synthesis were applied for catalytic oxidation of benzene. The results showed the ratios of citric acid/manganese nitrate in synthesizing process positively affected the physicochemical properties of MnOx, e.g., BET(Brunauer-Emmett-Teller) surface area, porous structure, reducibility and so on, which were in close relationship with their catalytic performance. Of all the catalysts, the sample prepared at a citric acid/manganese nitrate ratio of 2:1(C2M1) displayed the best catalytic activity with T(90)(the temperature when 90% of benzene was catalytically oxidized) of 212 ℃. Further investigation showed that C2M1 was Mn2O3 with abundant nano-pores, the largest surface area and the proper ratio of surface Mn^4+/Mn^3+, resulting in preferable low-temperature reducibility and abundant surface active adsorbed oxygen species. The analysis results of the in-situ Fourier transform infrared spectroscopy(in-situ FTIR) revealed that the benzene was successively oxidized to phenolate, o-benzoquinone, small molecules(such as maleates, acetates, and vinyl), and finally transformed to CO2 and H2O.

关键词： Catalytic activity Benzene oxidation Porous manganese oxides citric acid Solution combustion

Enhanced degradation of trichloroethene by calcium peroxide activated with Fe（III） in the presence of citric acid

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Frontiers of Environmental Science & Engineering 2016年第3期10卷 502-512页

作者： Xiang ZHANG Xiaogang GU Shuguang LU Zhouwei MIAO Minhui XU Xiaori FU Muhammad DANISH Mark L. BRUSSEAU Zhaofu QIU Qian SUI State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process East China University of Science and Technology Shanghai 200237 China Soil Water and Environmental Science Department School of Earth and Environmental Sciences The University of Arizona 429 Shantz Building Tucson AZ 85721 United States

Trichloroethene （TCE） degradation by Fe（III）- activated calcium peroxide （CP） in the presence of citric acid （CA） in aqueous solution was investigated. The results demonstrated that the presence of CA enhanced TCE degradation significantly by increasing the concen- tration of soluble Fe（III） and promoting H202 generation. The generation of HO· and O2^-· in both the CP/Fe（III） and CP/Fe（III）/CA systems was confirmed with chemical probes. The results of radical scavenging tests showed that TCE degradation was due predominantly to direct oxidation by HO·, while O2^-· strengthened the generation of HO· by promoting Fe（III） transformation in the CP/Fe （III）/CA system. acidic pH conditions were favorable for TCE degradation, and the TCE degradation rate decreased with increasing pH. The presence of Cl·-, HCO3·-, and humic acid （HA） inhibited TCE degradation to different extents for the CP/Fe（III）/CA system. Analysis of Cl·- production suggested that TCE degradation in the CP/Fe （III）/CA system occurred through a dechlorination process. In summary, this study provided detailed information for the application of CA-enhanced Fe（III）-activated calcium peroxide for treating TCE contaminated groundwater.

关键词： calcium peroxide trichloroethene （TCE） citric acid ferric ion free radicals oxidation

Synthesis of Mesoporous, Nanocrystalline Lanthanum Phosphate in the Presence of citric acid and Stearic acid

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Journal of Rare Earths 2007年第6期25卷 684-691页

作者： Li-Ngee Ho Hiroyasu Nishiguchi Katsutoshi Nagaoka Yusaku Takita Department of Applied Chemistry Oita University Dannoharu 700 Oita 870-1192 Japan

Lanthanum phosphate was prepared in the presence of citric acid and stearic acid under methanolic conditions at pH 4.5 and pH 7, respectively. The samples obtained were intensively characterized using X-ray diffraction, nitrogen adsorption-desorption isotherm study, transmission electron microscopy （TEM）, thermal gravimetric and differential thermal analysis, and Fourier transform infrared （FTIR） analysis . The as-synthesized samples prepared at pH 4.5 showed lamellar mesostruroned form with high crystallinity. Results showed that the pore size and pore volume changed when the materials were prepared under different pH conditions. Morphology of the samples was observed by using TEM, which showed that the samples possessed relatively small particles closely packed together. The as-synthesized samples were investigated using FTIR, and the mesopore formation mechanism was discussed.

关键词： mesoporous lanthanum phosphate citric acid stearic acid nanocrystalline rare earths