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Study on synergistic leaching of potassium and phosphorus from potassium feldspar and solid waste phosphogypsum via coupling reactions

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Chinese Journal of Chemical Engineering 2024年第1期65卷 117-129页

作者： Chao Li Shizhao Wang Yunshan Wang Xuebin An Gang Yang Yong Sun School of Chemical Engineering and Technology Hebei University of TechnologyTianjin 300130China National Engineering Research Center of Green Recycling for Strategic Metal Resources Chinese Academy of SciencesBeijing 100190China School of Engineering Edith Cowan University270 Joondalup DriveJoondalupWA 6027Australia Key Laboratory of Carbonaceous Wastes Processing and Process Intensification of Zhejiang Province The University of Nottingham Ningbo ChinaNingbo 315100China

To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study investigates the features of P and F in PG,and explores the decomposition of PF using hydrofluoric acid(HF)in the sulfuric acid system for K leaching and leaching of P and F in PG.The impact factors such as sulfuric acid concentration,reaction temperature,reaction time,material ratio(PG/PF),liquid–solid ratio,PF particle size,and PF calcination temperature on the leaching of P and K is systematically investigated in this paper.The results show that under optimal conditions,the leaching rate of K and P reach more than 93%and 96%,respectively.Kinetics study using shrinking core model(SCM)indicates two significant stages with internal diffusion predominantly controlling the leaching of K.The apparent activation energies of these two stages are 11.92 kJ·mol^(-1)and 11.55 kJ·mol^(-1),respectively.

关键词： Phosphogypsum Potassium feldspar coupling reaction Leaching Waste treatment Kinetics

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Direct coupling reaction of Diaryl Methanol with Ketones or Aldehydes Catalyzed by AlCl_(3)

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Chinese Journal of Chemistry 2014年第11期32卷 1176-1182页

作者： Zhiqiang Zhu Peng Bai Tiantian Wang Zhizhen Huang Department of Chemistry Zhejiang UniversityHangzhouZhejiang 310028China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

A novel coupling reaction of diaryl methanols with ketones or aldehydes has been developed under the catalysis of AlCl_(3).Various ketones and aldehydes could couple with 9H-xanthen-9-ol smoothly,affording coupling products in 48%-88%yields.A plausible mechanism using AlCl_(3) to activate both diaryl methanol and ketone or aldehyde is proposed.

关键词： coupling reaction alcohol ketone aldehyde AlCl_(3) catalysis

A facile approach to asymmetrical biaryls via coupling reaction of aryl halides with sodium tetraphenylborate catalyzed by MCM-41-supported sulfur palladium(0) complex

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Chinese Chemical Letters 2007年第4期18卷 387-389页

作者： Qiu Hua Xu Ping Ping Wang Ming Zhong Cai Department of Chemistry Jiangxi Normal University 330027 Nanchang China Department of Chemistry Jiujiang University 332000 Jiujiang China

Various functionalized asymmetrical biaryls can be synthesized in high to excellent yields via coupling reaction of aryl iodides or bromides with NaBPh4 catalyzed by MCM-41-supported sulfur palladium（0） complex. Thi... 详细信息

关键词： Asymmetrical biaryl NaBPh4 Aryl halide Palladium coupling reaction

An Efficient Palladium-catalyzed coupling reaction for the Preparation of Biaryls and Polyaryls

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Chinese Chemical Letters 2003年第1期14卷 13-16页

作者： Zhi Yong WANG Zheng Gen ZHA Jia Hai ZHANG Ji Hui WU Department of Chemistry University of Science and Technology of ChinaHefei 230026

In the case of Pd(PPh3)4 as catalyst and toluene as reaction solvent, the desired biaryls and polyaryls were synthesized in excellent yield and on a large scale.

关键词： Palladium-catalyst coupling reaction preparation biaryl polyaryl.

Preparation and Intramolecular C--C coupling reaction for Bis-benzimidazolium Salt

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Chinese Journal of Chemistry 2015年第9期33卷 1037-1040页

作者： Rui Liu Ran Huo Yue Bi Zhixiang Zhao Qingxiang Liu Tianjin Key Laboratory of Structure and Performance for Functional Molecules Key Laboratory ofInorganie-Organie Hybrid Funtional Material Chemistry Ministry of Education College of Chemistry Tianjin Normal University Tianjin 300387 China

Bis-benzimidazolium salt 1 was prepared via a series of reactions using 2,2＇-diphenol as starting material. Compound 2 was afforded through the intramolecular C--C coupling reaction of 1 under the catalysis of Pd（OAc）2. The structure of 2 is characterized through X-ray diffraction analyses, 1H NMR and 13C NMR. In 2, two boat-like seven-membered rings are contained, where the C--C bond distance newly formed is 1.461（5） A, and it is between regular C--C single bond （1.54 A） and C=C double bond （1.34 A）. This shows that new C--C bond has partial double-bond character. In the crystal packing of 2, the 2D supramolecular layers are formed via C--H..-F hydrogen bond.

关键词： bis-benzimidazolium salt coupling reaction palladium catalysis

Self-assembly Palladacycle Thiophene Imine Monolayer Investigating on Catalytic Activity and Mechanism for coupling reaction

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Chemical Research in Chinese Universities 2020年第5期36卷 821-828页

作者： LI Lun XUE Xiaoxia SUN Yimeng ZHAO Wuduo LI Tiesheng LIU Minghua WU Yangjie College of Chemistry Zhengzhou UniversityZhengzhou 450001P.R.China Henan Institute of Advanced Technology Zhengzhou UniversityZhengzhou 450001P.R.China Beijing National Laboratory for Molecular ScienceInstitute of ChemistryChinese Academy of SciencesBeijing 100190P.R.China

An ordered cyclopallated thiophene imine self-assembly monolayer(Si@Pd3TI)was designed and fkbri-cated.It was characterized by water contact angle(WCA),ultraviolet-visible spectroscopy(UV),cyclic voltanmie-try(CV),infrared(IR)spectrum,atomic force microscopy(AFM)and X-ray photoelectron spectroscopy(XPS).Its catalytic performance for Suzuki coupling reaction and catalytic mechanism were systematic investigated.Si@Pd3TI was validated as a heterogeneous catalyst identified by poisoning tests,hot filtration test and three-phase test.The heterogeneous catalytic mechanism was investigated by WCA,UY Raman spectrum(RS),AFM,XPS and density functional theory(DFT).The catalytic mechanism proceeded via surface-catalysis process,on which the Pd(Ⅱ)/Pd(Ⅰ)/Pd(0)synergistic active center acted likely as"multimetallic cluster".It played a great role for cataly-zing coupling reaction,in which the real active species was Pd(Ⅰ).

关键词： Cyclopalladated imine Thiophene coupling reaction Self-assembly monolayer Heterogeneous Synergistic

Facile synthesis of silicapolymer hybrids via simultaneous RAFT process and hydroxyl-alkoxysilane coupling reaction

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中国化学前沿:英文版 2011年第3期6卷 213-220页

作者： Chunnuan YE Weina QI Xinhua YU Peipei ZHANG Tengteng HOU Youliang ZHAO Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application Department of Polymer Science and EngineeringCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

This study aimed at the synthesis of silica particles grafted with better-defined homopolymers and block copolymers by tandem approach.Z-functionalized Sbenzyl S’-(3-trimethoxysilyl)propyltrithiocarbonate(BTPT)was used as a couplable RAFT agent to synthesize the target inorganic-organic hybrids.Simultaneous coupling reaction and RAFT process using silica particles and BTPT as raw materials efficiently afforded homopolymers grafted silica,and RAFTsynthesized macro chain transfer agents withω-terminal trimethoxysilane moiety were utilized to mediate graft reaction to prepare silica particles grafted with di-,tri-and tetrablock copolymers comprised of polymer segments such as polystyrene,polyacrylamides and polyacrylates.When the grafted chains had molecular weights ranging between 3920 and 24800 g/mol,the molar grafting ratios,which were dependent on reaction conditions and types and compositions of grafted chains,were estimated to be in the range of 15.2–101μmol/g,and grafted polymers usually had polydispersity indices lower than 1.3,revealing that the grafting process was almost controllable.To the best of our knowledge,this versatile tandem approach is one of the most facile techniques to prepare silica particles grafted with polymeric chains with controlled molecular weight,low polydispersity and precise composition due to its minimal reaction steps,mild conditions,straightforward synthesis and satisfactory controllability.

关键词： hybrid material reversible addition fragmentation chain transfer(RAFT) coupling reaction block copolymer surface modification

coupling reaction mechanism of 2-(2-bromo-4-fluorophenyl)-1-cyclohexen-1-yl trifluoromethane-sulfonate

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Journal of Chongqing University 2013年第3期12卷 108-116页

作者：白坤坤 YOU Yong PAN Rui 李来才 TIAN An-min Department of Chemistry Sichuan Normal University Department of Chemistry Sichuan University

The detailed mechanism of CuI-catalyzed C-O intramolecular coupling reaction of 2-(2-bromo-4-fluoro-phenyl)-1-cyclohexen-1-yl trifluoromethane–sulfonate was studied with the density functional theory(DFT). The geometries of the reactants,transition states, intermediates and products were optimized at the B3LYP/6-31+G* level. Meanwhile, the single point energy of species involved in gas and solvent at B3LYP/6-311+G* level was individually investigated. Polarizable continuum models(PCM)were applied to the dioxane and water solutions at the same level, respectively. Results show that the rate-limiting step, M3→TS3,does not change in different solutions. However, the activation energy in a dioxane solution is lower than that in water, which explains the previous experimental results. Compared with the non-catalyzed reaction process, the activation energy of the ratelimiting step is reduced by 56.53 kJ mol-1 in gas and 44.84 kJ mol 1in solvent, demonstrating a high catalytic efficiency of CuI.

关键词： 2-(2-bromo-4-fluoro-phenyl)-1-cyclohexen-1-yl trifluoromethane-sulfonate CuI density functional theory Calculation polarizable continuum model coupling reaction

New Palladium-Imidazole and Imidazoline Complexes:Structures and Reactivity in coupling reaction

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复旦学报（自然科学版） 2007年第5期46卷 768-页

作者： Satoshi Haneda Kazuo Eda Masahiko Hayashi Department of Chemistry Graduate School of ScienceKobe University

1 Results We have recently reported the Mizoroki-Heck reaction catalyzed by PdCl2 and imidazole ligands[1]. During the course of our study of palladium imidazole complex,we disclosed the synthesis of trans-Pd(Ln)2Cl2 by the reaction of PdCl2 with Ln (where L1=2-phenylimidazole,L2=2-phenylimidazole) in a 1∶2 molar ratio.The single crystals of trans-Pd(L1)2Cl2·2DMF (1a) and trans-Pd(L2)2Cl2 (2a) were obtained by following slow evaporation of DMF as a solvent. The single crystal of trans-Pd(L2)2Cl2 (2b) w...

关键词： palladium complex imidazole imidazoline X-ray analysis coupling reaction Mizoroki-Heck reaction