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Biogenic palladium prepared by activated sludge microbes for the hexavalent chromium catalytic reduction

Luman Zhou, Chengyang Wu, Yuwei Xie, Siqing Xia

《环境科学与工程前沿(英文)》 2020年 第14卷 第2期 doi: 10.1007/s11783-019-1206-4

摘要: • Pd nanoparticles could be reduced and supported by activated sludge microbes. • The effect of biomass on Pd adsorption by microbes is greater than Pd reduction. • More biomass reduces Pd particle size, which is more dispersed on the cell surface. • When the biomass/Pd add to 6, the catalytic reduction rate of Cr(VI) reaches stable. Palladium, a kind of platinum group metal, owns catalytic capacity for a variety of hydrogenations. In this study, Pd nanoparticles (PdNPs) were generated through enzymatic recovery by microbes of activated sludge at various biomass/Pd, and further used for the Cr(VI) reduction. The results show that biomass had a strong adsorption capacity for Pd(II), which was 17.25 mg Pd/g sludge. The XRD and TEM-EDX results confirmed the existence of PdNPs associated with microbes (bio-Pd). The increase of biomass had little effect on the reduction rate of Pd(II), but it could cause decreasing particle size and shifting location of Pd(0) with the better dispersion degree on the cell surface. In the Cr(VI) reduction experiments, Cr(VI) was first adsorbed on bio-Pd with hydrogen and then reduced using active hydrogen as electron donor. Biomass improved the catalytic activity of PdNPs. When the biomass/Pd (w/w) ratio increased to six or higher, Cr(VI) reduction achieved maximum rate that 50 mg/L of Cr(VI) could be rapidly reduced in one minute.

关键词: Palladium nanoparticles     Activated sludge     Hexavalent chromium    

Recent advances in selective acetylene hydrogenation using palladium containing catalysts

Alan J. McCue, James A. Anderson

《化学科学与工程前沿(英文)》 2015年 第9卷 第2期   页码 142-153 doi: 10.1007/s11705-015-1516-4

摘要: Recent advances with Pd containing catalysts for the selective hydrogenation of acetylene are described. The overview classifies enhancement of catalytic properties for monometallic and bimetallic Pd catalysts. Activity/selectivity of Pd catalysts can be modified by controlling particle shape/morphology or immobilisation on a support which interacts strongly with Pd particles. In both cases enhanced ethylene selectivity is generally associated with modifying ethylene adsorption strength and/or changes to hydride formation. Inorganic and organic selectivity modifiers (i.e., species adsorbed onto Pd particle surface) have also been shown to enhance ethylene selectivity. Inorganic modifiers such as TiO change Pd ensemble size and modify ethylene adsorption strength whereas organic modifiers such as diphenylsulfide are thought to create a surface template effect which favours acetylene adsorption with respect to ethylene. A number of metals and synthetic approaches have been explored to prepare Pd bimetallic catalysts. Examples where enhanced selectivity is observed are generally associated with decreased Pd ensemble size and/or hindering of the ease with which an unselective hydride phase is formed for Pd. A final class of bimetallic catalysts are discussed where Pd is not thought to be the primary reaction site but merely acts as a site where hydrogen dissociation and spillover occurs onto a second metal (Cu or Au) where the reaction takes place more selectively.

关键词: acetylene     ethylene     selective hydrogenation     palladium     bimetallic    

Effect of alkyl nitrite decomposition on catalytic performance of CO coupling reaction over supported palladium

Zhenhua LI, Weihan WANG, Dongxue YIN, Jing LV, Xinbin MA

《化学科学与工程前沿(英文)》 2012年 第6卷 第4期   页码 410-414 doi: 10.1007/s11705-012-1213-5

摘要: The syntheses of dimethyl oxalate (DMO) and diethyl oxalate (DEO) by CO coupling reaction in gaseous phase were investigated in a fixed bed reactor over Pd-Fe/Al O catalyst. The catalytic performance was characterized by CO conversion, space-time yield (STY) and selectivity of DMO (or DEO). The results showed that over Pd-Fe/Al O catalyst, the STY of DMO was higher than that of DEO under the same reaction conditions. The optimum reaction temperatures for synthesizing DMO and DEO were 403 K and 393 K, respectively, at the molar ratio 1 ∶ 1 of alkyl nitrite to CO. The difference in synthesizing DMO and DEO on the same catalyst was attributed to the decomposition performances of methyl nitrite (MN) and ethyl nitrite (EN), as density functional theory (DFT) calculation showed that EN decomposed more easily than MN.

关键词: palladium     CO coupling     dialkyl oxalate     alkyl nitrite     decomposition    

Experimental research on thermal transport properties of crystallized palladium-based alloys

Siyuan CHENG, Xuguo SHI, Weigang MA, Xing ZHANG, Guanglai LIU, Mingxiang PAN, Weihua WANG

《能源前沿(英文)》 2018年 第12卷 第1期   页码 121-126 doi: 10.1007/s11708-018-0531-9

摘要: Palladium-based alloy is a kind of material with a high glass forming ability and can be easily formed into an amorphous state. After an annealing process, it can also be maintained at a crystallized state. To study the thermal and electrical transport properties of crystallized palladium-based alloys, the steady-state T-type method, standard four-probe method, and AC heating-DC detecting T-type method were used to measure the thermal conductivity, electrical conductivity, and Seebeck coefficient of crystallized Pd Ni Cu P and Pd Ni Cu P alloys respectively. The results show that compared to amorphous samples, the thermal conductivity and electrical conductivity of crystallized palladium-based alloys are significantly higher, while the Seebeck coefficient is lower. The ratio of crystallized and amorphous thermal conductivity is higher for Pd Ni Cu P alloy fiber which has a higher glass forming ability, while the ratio of electronic thermal conductivity almost remains constant for both alloy fibers. The results also show that the slope of electrical resistivity to temperature is a function of elemental composition for crystallized quaternary palladium-based alloy fibers. The sensitivity of thermal conductivity and electrical conductivity to the composition is high, while the correlation between Seebeck coefficient and composition is relatively weak.

关键词: palladium-based alloy     T-type method     thermal conductivity     electrical conductivity     Seebeck coefficient    

Copolymerization of polyketones catalyzed by polyacrylonitrile resin-supported palladium acetate

GUO Jintang, ZHANG Hongxin, WANG Bo, YE Yaqin

《化学科学与工程前沿(英文)》 2008年 第2卷 第2期   页码 165-170 doi: 10.1007/s11705-008-0010-7

摘要: The crosslinked polyacrylonitrile (PAN) was synthesized by suspension polymerization using acrylonitrile (ANT) and divinylbenzene (DVB). Effects of a variety of conditions on the polymerization of PAN particle size and stiffness were investigated. Polyketone was prepared by the copolymerization of carbon monoxide (CO) and styrene (ST) catalyzed by PAN resin-supported palladium acetate. The resin-supported catalyst and the copolymerization product were characterized by infrared spectroscopy (IR) and Scanning Electron Microscopy (SEM). Effects of the components of a catalytic system and reaction time on the catalytic activity were studied. The reusability of the resin-supported catalyst was also investigated. Results indicated that the resin-supported catalyst has excellent catalytic property. The yield of polyketone was 6.2348 g when using 1 g of resin and 22.4 mg of palladium acetate.

关键词: copolymerization     Electron Microscopy     monoxide     excellent catalytic     Polyketone    

Facile synthesis of isoindoline-1,3-diones by palladium-catalyzed carbonylative cyclization of

Mayur V. KHEDKAR, Bhalchandra M. BHANAGE

《化学科学与工程前沿(英文)》 2013年 第7卷 第2期   页码 226-232 doi: 10.1007/s11705-013-1321-x

摘要: A facile method for the carbonylative cyclization of -bromobenzoic acid with primary amine using Pd(OAC) as a metal precursor and 1,1'-bis(diphenylphosphino)ferrocene (dppf) as a ligand has been developed. The effect of various reaction parameters such as ligand, solvent, base, time and temperature on this cyclization was studied. The optimized protocol was used for a wide variety of substituted aryl amines with different steric and electronic properties, affording the corresponding isoindoline-1,3-diones in good to excellent yields under atmospheric pressure of carbon monoxide at 100°C within 10 h using 1,4-diazabicyclo[2.2.2]octane (DABCO) as a base. The reaction system finds attractive alternative to the conventional multistep synthetic process and thus represents an effective utilization of carbonylative protocol for synthesis of valuable chemicals.

关键词: carbonylative cyclization reactions     isoindole-1     3-dinones     homogeneous catalysis     dppf    

Catalysis of semihydrogenation of acetylene to ethylene: current trends, challenges, and outlook

《化学科学与工程前沿(英文)》 2022年 第16卷 第7期   页码 1031-1059 doi: 10.1007/s11705-021-2113-3

摘要: Ethylene is an important feedstock for various industrial processes, particularly in the polymer industry. Unfortunately, during naphtha cracking to produce ethylene, there are instances of acetylene presence in the product stream, which poisons the Ziegler–Natta polymerization catalysts. Thus, appropriate process modification, optimization, and in particular, catalyst design are essential to ensure the production of highly pure ethylene that is suitable as a feedstock in polymerization reactions. Accordingly, carefully selected process parameters and the application of various catalyst systems have been optimized for this purpose. This review provides a holistic view of the recent reports on the selective hydrogenation of acetylene. Previously published reviews were limited to Pd catalysts. However, effective new metal and non-metal catalysts have been explored for selective acetylene hydrogenation. Updates on this recent progress and more comprehensive computational studies that are now available for the reaction are described herein. In addition to the favored Pd catalysts, other catalyst systems including mono, bimetallic, trimetallic, and ionic catalysts are presented. The specific role(s) that each process parameter plays to achieve high acetylene conversion and ethylene selectivity is discussed. Attempts have been made to elucidate the possible catalyst deactivation mechanisms involved in the reaction. Extensive reports suggest that acetylene adsorption occurs through an active single-site mechanism rather than via dual active sites. An increase in the reaction temperature affords high acetylene conversion and ethylene selectivity to obtain reactant streams free of ethylene. Conflicting findings to this trend have reported the presence of ethylene in the feed stream. This review will serve as a useful resource of condensed information for researchers in the field of acetylene-selective hydrogenation.

关键词: selectivity     hydrogenation     acetylene     ethylene     palladium    

Pd nano-catalyst supported on biowaste-derived porous nanofibrous carbon microspheres for efficient catalysis

《化学科学与工程前沿(英文)》 2023年 第17卷 第9期   页码 1289-1300 doi: 10.1007/s11705-023-2299-7

摘要: Environmental pollution caused by the presence of aromatic aldehydes and dyes in wastewater is a serious global concern. An effective strategy for the removal of these pollutants is their catalytic conversion, possibly to valuable compounds. Therefore, the design of efficient, stable and long-lifetime catalysts is a worthwhile research goal. Herein, we used nanofibrous carbon microspheres (NCM) derived from the carbohydrate chitin present in seafood waste, and characterized by interconnected nanofibrous networks and N/O-containing groups, as carriers for the manufacture of a highly dispersed, efficient and stable Pd nano-catalyst (mean diameter ca. 2.52 nm). Importantly, the carbonised chitin’s graphitized structure, defect presence and large surface area could promote the transport of electrons between NCM and Pd, thereby endowing NCM supported Pd catalyst with high catalytic activity. The NCM supported Pd catalyst was employed in the degradation of some representative dyes and the chemoselective hydrogenation of aromatic aldehydes; this species exhibited excellent catalytic activity and stability, as well as applicability to a broad range of aromatic aldehydes, suggesting its potential use in green industrial catalysis.

关键词: biowaste chitin     nanofibrous     palladium     nano-catalyst     catalysis    

Enhanced performances in catalytic oxidation of

Nanli QIAO,Xin ZHANG,Chi HE,Yang LI,Zhongshen ZHANG,Jie CHENG,Zhengping HAO

《环境科学与工程前沿(英文)》 2016年 第10卷 第3期   页码 458-466 doi: 10.1007/s11783-015-0802-1

摘要: A series of hierarchical macro-/mesoporous silica supports (MMSs) were successfully synthesized using dual-templating technique employing polystyrene (PS) spheres and the Pluronic P123 surfactant. Pd was next loaded on the hierarchical silica supports via colloids precipitation method. Physicochemical properties of the synthesized samples were characterized by various techniques and all catalysts were tested for the total oxidation of -xylene. Among them, the Pd/MMS-b catalyst with tetraethoxysilane/polystyrene weight ratio of 1.0 exhibited superior catalytic activity, and under a higher gas hourly space velocity (GHSV) of 70000 h , the 90% conversion of -xylene has been obtained at around 200°C. The BET and SEM results indicated that Pd/MMS-b catalyst possesses high surface area and large pore volume, and well-ordered, interconnected macropores and 2D hexagonally mesopores hybrid network. This novel ordered hierarchical porous structure was highly beneficial to the dispersion of active sites Pd nanoparticles with less aggregation, and facilitates diffusion of reactants and products. Furthermore, the Pd/MMS-b catalyst possessed good stability and durability.

关键词: hierarchical macro-/mesoporous     silica     palladium     VOCs catalytic oxidation    

Electrocatalytic debromination of BDE-47 at palladized graphene electrode

Hongtao YU, Bin MA, Shuo CHEN, Qian ZHAO, Xie QUAN, Shahzad AFZAL

《环境科学与工程前沿(英文)》 2014年 第8卷 第2期   页码 180-187 doi: 10.1007/s11783-013-0552-x

摘要: Graphene electrodes (Ti/Gr) were prepared by depositing Gr sheets on Ti substrate, followed by an annealing process for enhancing the adhesion strength. Electrochemical impedance spectroscopies and X-ray diffraction patterns displayed that the electrochemical behavior of Ti/Gr electrodes can be improved due to the generation of TiO layer at Ti-Gr interface during the annealing process. The palladized Gr electrodes (Ti/Gr/Pd) were prepared by electrochemical depositing Pd nanoparticles on Gr sheets. The debromination ability of Ti/Gr/Pd electrodes was investigated using BDE-47 as a target pollutant with various bias potentials. The results indicated that the BDE-47 degradation rates on Ti/Gr/Pd electrodes increased with the negative bias potentials from 0 V to -0.5 V (vs. SCE). Almost all of the BDE-47 was removed in the debromination reaction on the Ti/Gr/Pd electrode at -0.5 V for 3 h, and the main product was diphenyl ethers, meaning it is promising to debrominate completely using the Ti/Gr/Pd electrode. Although the debromination rate was slightly slower at -0.3 V than that under -0.5 V, the current efficiency at -0.3 V was higher, because the electrical current acted mostly on BDE-47 rather than on water.

关键词: graphene     palladium     debromination     BDE-47    

Removal of dissolved oxygen from water using a Pd-resin based catalytic reactor

Wenxin SHI, Chongwei CUI, Liye ZHAO, Shuili YU, Xia YUN

《化学科学与工程前沿(英文)》 2009年 第3卷 第1期   页码 107-111 doi: 10.1007/s11705-009-0154-0

摘要: The removal of dissolved oxygen (DO) from water was studied experimentally in a Pd-resin base catalyst reactor using purified hydrogen gas as a reducing agent. The effects of various operating conditions, such as hydrogen and water flow rates, height of the catalytic resin bed, temperature, pH value and run time, on the removal of DO, had been studied extensively. The results shows that DO could be removed by the reactor from ppm to ppb levels at ambient temperature. Increases of temperature, H gas rate and the height of the catalytic resin were helpful to improve the DO removal rate. The change of pH value from 4 to 12 resulted in no effect on DO removal. Reaction time was the key factor to control the DO removal efficiency. Only when the reaction time was longer than 2.3 minutes under the experimental conditions, could a very low DO level be achieved.

关键词: dissolved oxygen     palladium     catalytic reactor     hydrogen     resin    

2-Aminopyridine functionalized cellulose based Pd nanoparticles: An efficient and ecofriendly catalyst for the Suzuki cross-coupling reaction

Peibo Hu,Yahao Dong,Xiaotian Wu,Yuping Wei

《化学科学与工程前沿(英文)》 2016年 第10卷 第3期   页码 389-395 doi: 10.1007/s11705-016-1575-1

摘要: A palladium catalyst supported on 2-aminopyridine functionalized cellulose was synthesized and fully characterized by inductively coupled plasma atomic emission spectroscopy, transmission electron microscope, Fourier transform infrared spectroscopy, thermogravimetric analysis and X-ray photoelectron spectrometry. This catalyst can be applied in the Suzuki cross-coupling reaction of aryl halides with arylboronic acids in 50% ethanol to afford biaryls in?good yields, and easily recycled by simple filtration after reaction without the loss of metal Pd.

关键词: cellulose-supported     2-aminopyridine     palladium nanoparticles     ecofriendly catalyst     Suzuki cross-coupling reaction    

Investigation of the preparation methodologies of Pd-Cu single atom alloy catalysts for selective hydrogenation of acetylene

Xinxiang Cao,Arash Mirjalili,James Wheeler,Wentao Xie,Ben W.-L. Jang

《化学科学与工程前沿(英文)》 2015年 第9卷 第4期   页码 442-449 doi: 10.1007/s11705-015-1547-x

摘要: Galvanic replacement, co-impregnation and sequential impregnation have been employed to prepare Pd-Cu bimetallic catalysts with less than 1 wt-% Cu and ca. 0.03 wt-% Pd for selective hydrogenation of acetylene in excess ethylene. High angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) and H chemisorption results confirmed that Pd-Cu single-atom alloy structures were constructed in all three bimetallic catalysts. Catalytic tests indicated that when the conversion of acetylene was above 99%, the selectivity of ethylene of these three single atom alloy catalysts was still more than 73%. Furthermore, the single atom alloy catalyst prepared by sequential incipient wetness impregnation was found to have the best stability among the three procedures used.

关键词: H2 pulse chemisorption     palladium-copper bimetallic catalyst     single atom alloy     acetylene hydrogenation     HAADF-STEM    

Preparation and investigation of Pd doped Cu catalysts for selective hydrogenation of acetylene

Xinxiang Cao, Tengteng Lyu, Wentao Xie, Arash Mirjalili, Adelaide Bradicich, Ricky Huitema, Ben W.-L. Jang, Jong K. Keum, Karren More, Changjun Liu, Xiaoliang Yan

《化学科学与工程前沿(英文)》 2020年 第14卷 第4期   页码 522-533 doi: 10.1007/s11705-019-1822-3

摘要: A series of PdCu bimetallic catalysts with low Cu and Pd loadings and different Cu: Pd atomic ratios were prepared by conventionally sequential impregnation (CSI) and modified sequential impregnation (MSI) of Cu and Pd for selective hydrogenation of acetylene. Characterization indicates that the supported copper (II) nitrate in the PdCu bimetallic catalysts prepared by MSI can be directly reduced to Cu metal particles due to the hydrogen spillover from Pd to Cu(NO ) crystals. In addition, for the catalysts prepared by MSI, Pd atoms can form PdCu alloy on the surface of metal particles, however, for the catalysts prepared by CSI, Pd tends to migrate and exist below the surface layer of Cu. Reaction results indicate that compared with CSI, the MSI method enables samples to possess preferable stability as well as comparable reaction activity. This should be due to the MSI method in favor of the formation of PdCu alloy on the surface of metal particles. Moreover, even Pd loading is super low,<0.045 wt-% in this study, by through adjusting Cu loading to an appropriate value, attractive reactivity and selectivity still can be achieved.

关键词: copper     palladium     catalysts     acetylene     selective hydrogenation    

标题 作者 时间 类型 操作

Biogenic palladium prepared by activated sludge microbes for the hexavalent chromium catalytic reduction

Luman Zhou, Chengyang Wu, Yuwei Xie, Siqing Xia

期刊论文

Recent advances in selective acetylene hydrogenation using palladium containing catalysts

Alan J. McCue, James A. Anderson

期刊论文

Effect of alkyl nitrite decomposition on catalytic performance of CO coupling reaction over supported palladium

Zhenhua LI, Weihan WANG, Dongxue YIN, Jing LV, Xinbin MA

期刊论文

Experimental research on thermal transport properties of crystallized palladium-based alloys

Siyuan CHENG, Xuguo SHI, Weigang MA, Xing ZHANG, Guanglai LIU, Mingxiang PAN, Weihua WANG

期刊论文

Copolymerization of polyketones catalyzed by polyacrylonitrile resin-supported palladium acetate

GUO Jintang, ZHANG Hongxin, WANG Bo, YE Yaqin

期刊论文

Facile synthesis of isoindoline-1,3-diones by palladium-catalyzed carbonylative cyclization of

Mayur V. KHEDKAR, Bhalchandra M. BHANAGE

期刊论文

Catalysis of semihydrogenation of acetylene to ethylene: current trends, challenges, and outlook

期刊论文

Pd nano-catalyst supported on biowaste-derived porous nanofibrous carbon microspheres for efficient catalysis

期刊论文

Enhanced performances in catalytic oxidation of

Nanli QIAO,Xin ZHANG,Chi HE,Yang LI,Zhongshen ZHANG,Jie CHENG,Zhengping HAO

期刊论文

Electrocatalytic debromination of BDE-47 at palladized graphene electrode

Hongtao YU, Bin MA, Shuo CHEN, Qian ZHAO, Xie QUAN, Shahzad AFZAL

期刊论文

Removal of dissolved oxygen from water using a Pd-resin based catalytic reactor

Wenxin SHI, Chongwei CUI, Liye ZHAO, Shuili YU, Xia YUN

期刊论文

2-Aminopyridine functionalized cellulose based Pd nanoparticles: An efficient and ecofriendly catalyst for the Suzuki cross-coupling reaction

Peibo Hu,Yahao Dong,Xiaotian Wu,Yuping Wei

期刊论文

Investigation of the preparation methodologies of Pd-Cu single atom alloy catalysts for selective hydrogenation of acetylene

Xinxiang Cao,Arash Mirjalili,James Wheeler,Wentao Xie,Ben W.-L. Jang

期刊论文

Preparation and investigation of Pd doped Cu catalysts for selective hydrogenation of acetylene

Xinxiang Cao, Tengteng Lyu, Wentao Xie, Arash Mirjalili, Adelaide Bradicich, Ricky Huitema, Ben W.-L. Jang, Jong K. Keum, Karren More, Changjun Liu, Xiaoliang Yan

期刊论文