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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    

2-Aminopyridine functionalized cellulose based Pd nanoparticles: An efficient and ecofriendly catalyst

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    

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    

Translocation and biotoxicity of metal (oxide) nanoparticles in the wetland-plant system

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1432-4

摘要:

• Aquatic plants are more likely to absorb TiO2 NPs that are beneficial to them.

关键词: Constructed wetlands     Aquatic plants     Nanoparticles     Physiological activity     Biomass    

Enhanced 4-chlorophenol biodegradation by integrating FeO nanoparticles into an anaerobic reactor: Long-term

《环境科学与工程前沿(英文)》 2022年 第16卷 第8期 doi: 10.1007/s11783-022-1519-6

摘要:

• 4-chlorophenol biodegradation could be enhanced in Fe2O3 coupled anaerobic system.

关键词: Dechlorination     Fe2O3 nanoparticles     Electron transfer     Microbial community    

Gold nanoparticles/single-stranded DNA-reduced graphene oxide nanocomposites based electrochemical biosensor

《化学科学与工程前沿(英文)》 2021年 第15卷 第6期   页码 1572-1582 doi: 10.1007/s11705-021-2112-4

摘要: High density and uniform distribution of the gold nanoparticles functionalized single-stranded DNA modified reduced graphene oxide nanocomposites were obtained by non-covalent interaction. The positive gold nanoparticles prepared by phase inversion method exhibited good dimensional homogeneity and dispersibility, which could readily combine with single-stranded DNA modified reduced graphene oxide nanocomposites by electrostatic interactions. The modification of single-stranded DNA endowed the reduced graphene oxide with favorable biocompatibility and provided the preferable surface with negative charge for further assembling of gold nanoparticles to obtain gold nanoparticles/single-stranded DNA modified reduced graphene oxide nanocomposites with better conductivity, larger specific surface area, biocompatibility and electrocatalytic characteristics. The as-prepared nanocomposites were applied as substrates for the construction of cholesterol oxidase modified electrode and well realized the direct electron transfer between the enzyme and electrode. The modified gold nanoparticles could further catalyze the products of cholesterol oxidation catalyzed by cholesterol oxidase, which was beneficial to the enzyme-catalyzed reaction. The as-fabricated bioelectrode exhibited excellent electrocatalytic performance for the cholesterol with a linear range of 7.5‒280.5 μmol·L‒1, a low detection limit of 2.1 μmol·L‒1, good stability and reproducibility. Moreover, the electrochemical biosensor showed good selectivity and acceptable accuracy for the detection of cholesterol in human serum samples.

关键词: reduced graphene oxide     gold nanoparticles     electrochemical biosensor     cholesterol oxidase     cholesterol    

polymeric substances from activated sludge on the aggregation kinetics of silver and silver sulfide nanoparticles

《环境科学与工程前沿(英文)》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1450-2

摘要:

• The NPs aggregation in the electrolyte solution is consistent with the DLVO theory.

关键词: Silver nanoparticles     Silver sulfide nanoparticles     Extracellular polymeric substances     Aggregation kinetics     Influence mechanisms    

Size and shape effects of MnFeO nanoparticles as catalysts for reductive degradation of dye pollutants

《环境科学与工程前沿(英文)》 2021年 第15卷 第5期   页码 108-171 doi: 10.1007/s11783-021-1396-4

摘要: The magnetic nanoparticles that are easy to recycle have tremendous potential as a suitable catalyst for environmental toxic dye pollutant degradation. Rationally engineering shapes and tailoring the size of nanocatalysts are regarded as an effective manner for enhancing performances. Herein, we successfully synthesized three kinds of MnFe2O4 NPs with distinctive sizes and shapes as catalysts for reductive degradation of methylene blue, rhodamine 6G, rhodamine B, and methylene orange. It was found that the catalytic activities were dependent on the size and shape of the MnFe2O4 NPs and highly related to the surface-to-volume ratio and atom arrangements. Besides, all these nanocatalysts exhibit selectivity to different organic dyes, which is beneficial for their practical application in dye pollutant treatment. Furthermore, the MnFe2O4 NPs could be readily recovered by a magnet and reused more than ten times without appreciable loss of activity. The size and shape effects of MnFe2O4 nanoparticles demonstrated in this work not only accelerate further understanding the nature of nanocatalysts but also contribute to the precise design of nanoparticles catalyst for pollutant degradation.

关键词: Dye degradation     MnFe2O4 nanoparticles     Size and shape-control    

Functional magnetic nanoparticles for facile viable but nonculturable bacteria separation and purification

Chunming Wang, Huirong Lin, Chengsong Ye

《环境科学与工程前沿(英文)》 2016年 第10卷 第6期 doi: 10.1007/s11783-016-0874-6

摘要: The functional surface-modified MNPs were capable of capture with high efficiency. After induced to VBNC state by chlorination, cells could be separated by MNPs with an additional incubation process. This study provides a facile and economic method for VBNC cell enrichment and purification. GRAPHIC ABSTRACT Viable But Nonculturable (VBNC) Bacteria, which represent a unique population of microorganisms in drinking water systems, have become a potential threat to human health. Current studies on VBNC cells usually fail to obtain pure VBNC state bacteria, which may lead to inaccurate results. We therefore introduce a novel method of VBNC cell separation and purification in this paper. PAH-coated magnetic nanoparticles (MNPs) were synthesized and found to be capable of capturing and releasing bacterial cells with high efficiency. With the aid of an additional incubation step, VBNC cells were easily isolated and purified from normal bacteria using functional MNPs. Our method represents a new technique that can be utilized in studies of VBNCs.

关键词: Drinking water biosafety     VBNC     Nanoparticles     Magnetic separation and purification    

Size-controlled green synthesis of silver nanoparticles assisted by L-cysteine

Wenchao Zhang,Lin Zhang,Yan Sun

《化学科学与工程前沿(英文)》 2015年 第9卷 第4期   页码 494-500 doi: 10.1007/s11705-015-1527-1

摘要: A green and size-controlled synthesis of silver nanoparticles (Ag NPs) in aqueous solution with the assistance of L-cysteine is presented. The size of Ag NPs decreases with the increase of L-cysteine concentration, and thus can be controlled by adjusting L-cysteine concentration. TEM analysis shows that Ag NPs with an average size of 3 nm can be produced in the presence of 1.0 mmol/L L-cysteine, about one sixth of the size of Ag NPs obtained in the absence of L-cysteine (17 nm). The as-synthesized silver colloidal solution is stable and can be stored at room temperature for at least two months without any precipitation. This L-cysteine assisted method is simple, feasible and efficient, and would facilitate the production and application of Ag NPs.

关键词: nanoparticles     silver     L-cysteine     size distribution     synthesis    

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

2-Aminopyridine functionalized cellulose based Pd nanoparticles: An efficient and ecofriendly catalyst

Peibo Hu,Yahao Dong,Xiaotian Wu,Yuping Wei

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

Translocation and biotoxicity of metal (oxide) nanoparticles in the wetland-plant system

期刊论文

Enhanced 4-chlorophenol biodegradation by integrating FeO nanoparticles into an anaerobic reactor: Long-term

期刊论文

Gold nanoparticles/single-stranded DNA-reduced graphene oxide nanocomposites based electrochemical biosensor

期刊论文

polymeric substances from activated sludge on the aggregation kinetics of silver and silver sulfide nanoparticles

期刊论文

Size and shape effects of MnFeO nanoparticles as catalysts for reductive degradation of dye pollutants

期刊论文

Functional magnetic nanoparticles for facile viable but nonculturable bacteria separation and purification

Chunming Wang, Huirong Lin, Chengsong Ye

期刊论文

Size-controlled green synthesis of silver nanoparticles assisted by L-cysteine

Wenchao Zhang,Lin Zhang,Yan Sun

期刊论文