XRD and SEM characterization of Cu/Co catalysts supported on Si-Al-zeolite made by a modified sol-gel technique

Cu, Co and Cu/Co catalysts supported on a Si-Al-Zeolite matrix, made by a modified sol-gel method, were characterized by XRD and SEM. The formation of some spinels was identified in some of the samples. Of particular interest were those spinels whose composition included Cu and Co in a mixed oxide. The identification of such structures would explain higher activities in those catalysts. This revised version was published online in June 2006 with corrections to the Cover Date.     

Schiff碱配合物的研究——Ⅸ.表面Schiff碱配合物对H_2O_2分解的催化作用

制备了两种表面Schiff碱及其Cu~(2+)、Co~(2+)、Ni~(2+)、Zn~(2+)配合物,考察了它们对H_2O_2分解的催化性能,其活性顺序为:Co~(2+)>Cu~(2+)>Ni~(2+)>Zn~(2+),且与金属离子氧化还原电位有关。溶液的pH值增加有利于催化反应,有机配体的加入则对反应有所抑制。     

铁酸盐催化剂上乙醇的催化燃烧

用共沉淀法制备了N i,Co,Cu等的铁酸盐复合氧化物催化剂,并采用XRD、IR等手段对催化剂进行了表征,结果表明具有尖晶石结构的CuFe2O4复合氧化物催化剂对乙醇催化燃烧反应具有较高活性和选择性,Co部分掺杂的CuFe2O4其活性和选择性有所提高,乙醇可在约229℃达到完全转化,燃烧产物中没有发现乙醛副产物.     

Effect of Transition Metals (Cu, Co and Fe) on the Autothermal Reforming of Methane over Ni/Ce0.2Zr0.1Al0.7Oδ Catalyst

The transition metals (Cu, Co, and Fe) were applied to modify Ni/Ce0.2Zr0.1Al0.7Oδ catalyst.The effects of transition metals on the catalytic properties of Ni/Ce0.2Zr0.1Al0.7Oδ autothermal reforming of methane were investigated. The Ni-supported catalysts were characterized by XRD, TPR and XPS.Tests in autothermal reforming of methane to hydrogen showed that the addition of transition metals (Cu and Co) significantly increased the activity of catalyst under the conditions of lower reaction temperature,and Ni/Cu0.05Ce0.2Zr0.1Al0.65Oδ was found to have the highest conversion of CH4 among all catalysts in the operation temperatures ranging from 923 K to 1023 K. TPR, XRD and XPS measurements indicated that the cubic phases of CexZr1-xO2 solid solution were formed in the preparation process of catalysts.Strong interaction was found to exist between NiO and CexZr1-xO2 solid solution. The addition of Cu improved the dispersion of NiO, inhibited the formation of NiAl2O4, and thus significantly promoted the activity of the catalyst Ni/Cu0.05Ce0.2Zr0.1Al0.65Oδ.     

改良铜钴催化剂体系上由合成气制混合醇的研究

在铜钴基催化剂体系上，由合成气制备混合醇的反应在６．０ＭＰａ的条件下进行．双活性组分体系中铜和钴是以强相互作用状态而共存的，分子探针实验表明，铜和钴的并存对于确保醇的碳链增长是重要的，助剂ＭｏＯ_ｘ的加入显著提高了Ｌａ_２Ｚｒ_２Ｏ_７担载的铜钴基催化剂Ｃｏ／ＣｕＬＺ的活性和选择性，其作用主要表现为通过氢的可逆溢流效应而改善了体系的氢化性能，和增大了ＣＯ的插入反应能力。在改良催化剂体系上，获得了５３％的醇选择性和１４７ｇ／Ｋｇｃａｔ／ｈ的混合醇产率，内含３３％的高级醇。     

3d Metal complexes with 2-hydroxy-3-methoxybenzaliminopropyl and 4-hydroxy-3-methoxybenzaliminopropyl immobilized on aerosil as catalysts of ozone decomposition

The composition and structure of M(II) (Mn, Co, Cu) complexes with Schiff bases (L1 = 2-hydroxy-3-methoxybenzaliminopropyl, L2 = 4-hydroxy-3-methoxybenzaliminopropyl) immobilized on Aerosil and their catalytic activity in ozone decomposition were studied. The formation of pseudotetrahedral bisligand complexes M(L1)₂ and pseudooctahedral complexes M(L2)₂ on the modified surface of Aerosil was confirmed by IR and ESR spectroscopy and by diffuse reflectance spectroscopy (DSR). The catalytic activity of isostructural complexes in ozone decomposition varies in the order Mn > Co > Cu, and M(L₂)₂ complexes are more active than M(L1)₂.     

CuxCo1-x/Al2O3/堇青石整体式催化剂的制备及其催化甲苯燃烧性能

以堇青石蜂窝陶瓷为基底,A12O3浆料为过渡胶体,Cu和Co为催化活性组分,制备了一系列CuxCo1-x/Al2O3/堇青石(x=0～1)整体式催化剂.采用X射线衍射、X射线光电子能谱、扫描电镜和程序升温还原等手段对催化剂进行了表征.以甲苯为模型化合物.在微型固定床反应器上评价了催化剂的催化性能.结果表明,当Cu含量较...     

Removal of biomass tar by steam reforming over calcined scallop shell supported Cu catalysts

In this study, the main purpose is to develop low-cost catalysts with high activity and stability for high quality syngas production via steam reforming of biomass tar in biomass gasification process. The calcined waste scallop shell(CS) supported copper(Cu) catalysts are prepared for steam reforming of biomass tar. The prepared Cu supported on CS catalysts exhibit higher catalytic activity than those on commercial CaO and Al_2O_3. Characterization results indicate that Cu/CS has a strong interaction between Cu and CaO in CS support, resulting in the formation of calcium copper oxide phase which could stabilize Cu species and provide new active sites for the tar reforming. In addition, the strong basicity of CS support and other inorganic elements contained in CS support could enhance the activity of Cu/CS. The addition of a small amount of Co is found to be able to stabilize the catalytic activity of Cu/CS catalysts,making them reusable after regeneration without any loss of their activities.     

OXIDATIVE ETHOXYCARBONYLATION OF ANILINE TO ETHYL PHENYLCARBAMATE CATALYZED BY SILICA- SUPPORTED POLY-γ-AMINOPROPYLSILOXANEMETAL COMPLEXES

Several silica-supported poly-γ-aminopropylsiloxane-monometal and bimetal complexes (Si-NH_2-M,M = Cu or Co ; Si-NH_2-Cu-M', M' =Co, Sn, Mn, Ni or Fe) have been prepared. Their catalytic properties for oxidative ethoxycarbonylation of aniline to ethyl phenylcarbamate have been investigated.The catalytic reaction was carried out under relatively mild conditions. The catalyst Si-NH_2-Cu-CO had high activity and selectivity, and the turn-over number (molar of aniline converted/molar of metal in Si-NH_2-Cu-CO added) could amount to 450 under the conditions: 150℃, 4 MPa (CO/O_2 =3) and 40 hours.The results of XPS and IR indicated that the coordination bonds were formed between nitrogen and metals in Si-NH2-Cu, Si-NH_2-Co and Si-NH_2-Cu-Co, and the coordination pattern was not single. In the oxidative ethoxycarbonylation of aniline to ethyl phenylcarbamate, the catalytic property of Si-NH_2-Cu-CO bimetallic complex was better than Si-NH_2-Cu or Si-NH_2-Co monometatlic complex. This indicated that there was synergistic action between different metals in the bimetallic complex.     

水杨醛缩2-氨基-4-苯基噻唑及其配合物的合成与仿酶催化活性研究

The new containing Surfur Schiff base Salicylaldelye-2-amino-4-Phenylthiazole(SAPTZ) and its Cu(Ⅱ)、Zn(Ⅱ)、Ni(Ⅱ) and Co(Ⅱ) compelexes were synthesized. The structures of the complexes were characterized by elemental analysis, IR and UV-vis. The peroxidase-like activity of the complexes for the oxidation of Vc with H₂O₂ was determined.     

STUDIES ON THE CATALYTIC REACTION OF NITROGEN OXIDE ON METAL MODIFIED ACTIVATED CARBON FIBERS

The catalytic reaction of NO with CO and decomposition of NO over metal modified ACFs were investigated and compared with other carriers supported catalysts. It is demonstrated that Pd/ACF and Pd/Cu/ACF have high catalytic activity for the reaction of NO/CO, while Pt/ACE. Pt/Cu/ACF and Co/Cu/ACF have very low catalytic activity in similar circumstance. Pd-modified ACF possesses high catalytic decomposition of NO at 300℃. Pd/CB and Pd/GAC present good catalytic decomposition abifity for NO only at low [lowrate. Pd/G Pd/ZMS and Pd/A however, do not show any catalytic activity for NO decomposition even at 400 ℃. Catalytic temperature, NO flowrate and loading of metal components affect the decomposition rate of NO. The coexistence of Cu with Pd on Cu/Pd/ACF leads to crystalline of palladium to more unperfected so as to that increase the catalytic activity.     

过渡金属掺杂二氧化钛光催化性能的研究

采用浸渍法制备了过渡金属掺杂的光催化剂MOx/TiO2(M=Cr、Mn、Fe、Co、Ni、Cu).以乙酸的光催化氧化降解反应为探针,研究了催化剂的光催化性能.研究结果表明,经过渡金属掺杂改性的二氧化钛,光催化性能都有所提高.掺杂量有一个最佳值,在最佳掺杂量时,催化剂光催化性能的提高程度与对应金属氧化物的生成焓有很好的一致性,还发现光催化性能与过渡金属离子稳定氧化态的电子亲和势与离子半径的比值间呈现火山型关系曲线.     

荧光法研究芦丁-Cu2+/CO2+-BSA的相互作用

采用荧光光谱、紫外-可见光谱技术研究了芦丁与牛血清白蛋白(BSA)在金属离子Cu2+/CO2+共存时的相互作用.研究结果表明:有或无金属离子存在时,芦丁对BSA的荧光猝灭作用都是由于生成复合物而引起的静态猝灭;金属离子的存在使芦丁与BSA的表观结合常数KLB增大,且Co使KL)增大得更明显.由热力学参数确定芦丁和BSA...     

Determination of cobalt at ng ml(-1) level in water using the electrophilic substiution complexation between co(II) and chlorophosphonazo-p-CL-Cu(II) complex

The chromophore chlorophosphonazo-p-Cl (PCCPA) was used to complex Co(II) and Cu(II) at pH 9.18. The formation of Co(PCCPA)2 and Cu(PCCPA)2 complexes were characterized by the spectral correction technique. Co(II) could competitively substitute Cu(II) from the Cu(II)-PCCPA complex via electrophilic effect. With the assistance of the light-absorption ratio variation approach, the electrophilic substitution complexation showed a high selectivity and good sensitivity with 1.9 ng mL(-1) of LOD. The proposed method has been applied to the direct detection of Co(II) in surface water and wastewater with good percent of recovery.     

Cu(II)-3-(5-chlor-2-hydroxy-3-sulfophenylazo)-6-(2,4,6-tribromophenylazo)-4,5-dihydroxynaphthalene-2,7-disulfonic Acid-Co(II) binuclear complexation and its application to the selective determination of cobalt at ng/ml level.

The chromophore, 3-(5-chlor-2-hydroxy-3-sulfophenylazo)-6-(2,4,6-tribromophenylazo)-4,5-dihydroxynaphthalene-2,7-disulfonic acid (CSTDD) was used to complex Cu(II) and Co(II) in aqueous solution at pH 9.43. A binuclear complex of Cu-CSTDD-Co was formed and showed a high selectivity for the determination of Co(II). The spectral correction technique was applied to characterize the complexes. The results showed the formation of complexes of Cu(CSTDD), Co(CSTDD)3 and Cu2(CSTDD)2Co. The quantitative analysis of Co(II) at ng/ml level was carried out by the light-absorption ratio variation approach (LARVA). The results showed that the technique is satisfactory to determine Co(II) at trace level in water samples with a detection limit of 2.3 ng/ml.     

EFFECT OF THE DEGREE OF DVB CROSSLINKING ON THE METAL ION SPECIFICITY OF POLYACRYLAMIDE-SUPPORTED GLYCINES

Metal ion specificity studies of divinylbenzene (DVB)-crosslinked polyacrylamide-supported glycines in different structural environments were investigated. The effect of the degree of crosslinking on the specific rebinding of the desorbed metal ion was investigated towards Co(II), Ni(II), Cu(II), and Zn(II) ions. The metal ion-desorbed resins showed specificity for the desorbed metal ion and the specificity characteristics increases with an increasing degree of the crosslinking agent. The polymeric ligands and metal complexes were characterized by IR, UV-visible and EPR spectra, and by SEM analysis. The swelling and solvation characteristics of the crosslinked polymers, polymeric ligands and metal complexes, the effect of the pH dependence on metal ion binding and rebinding and the kinetics of metal ion binding and rebinding were also followed. The complexation resulted in the downfield shift of the carboxylate peak in the IR spectra. The EPR parameters are in agreement with a distorted tetragonal geometry. The Cu(II) ion-desorbed resins selectively rebinds Cu(II) ions from a mixture of Cu(II) and Co(II) and Cu(II) and Ni(II) ions. The resin could be regenerated several times without loss of capacity and effective for the specific and selective rebinding of Cu(II) ions.     

COMPLEXATION OF METAL IONS WITH 3,5-DI-TERT-BUTYL-1,2-BENZOQUINONE-1-MONOOXIME,ESR STUDIES OF RADICAL INTERMEDIATES

Abstract

The possibility of chelate formation of 3,5-di-terf-butyl-o-benzoquinone-1-monooxime with Cu(II), Co(II), Ni(II), Mn(II), Pd(II) metal ions under N₂ and in air have been investigated. It was found that complexation of metals except Cu(II) and Mn(II) was accompanied by formation of various stable radical species under air. The complexation of Co(II) even under N₂ unlike other metal ions, results in the formation of very stable radical species, which are assigned to phenazinyl type radical. ESR examination of reduction of bis(3,5-di-tert-butyl-o-benzoquinone-1-monooximato)M(II) (M = Cu, Pd) with triarylphosphines P(C₆H₄ X)₃ (X = H, m-Cl, m-CH₃, p-Et₂N) reveal the formation of the N-(2′-hydroxy-3,5-di-tertbutylphenyl)-4′,6′-di-tertbutyl-o-benzosemiquinone iminate radical. Finally, ESR spectra of Cu(II), Ni(II), and Mn(II) complexes at 300 and 130 K, as well as reaction of bis(oximato)Ni(II) with PPh₃ have been studied.     

Acid equilibria of semi-methylthymol blue and formation constants of cobalt(II), nickel(II), copper(II) and zinc(II) complexes with semi-methylthymol blue

Potentiometric and spectrophotometric studies on Semi-Methylthymol Blue (SMTB or H(4)L) have been performed. The acid-base and Co(II), Ni(II), Cu(II) and Zn(II)-ligand reaction stoichiometries were determined, and the formation constants of the corresponding proton and metal complexes, and the molar absorptivities were calculated. Evidence was found for the formation of 1:1 Co(II), Ni(II) and Cu(II) complexes, and 1:1 and 1:2 Zn(II) complexes. Cu(II) formed the hydroxo-complex, Cu(OH)L(3-), but no hydroxo-complexes of the other metal ions were observed. Suggestions are made concerning the probable structure of the complexes.     

Poly(crotonic acid-co-2-acrylamido-2-methyl-1-propanesulfonic acid)-metal complexes with copper(II), cobalt(II), and nickel(II): Synthesis, characterization and antimicrobial activity

Poly(crotonic acid-co-2-acrylamido-2-methyl-1-propanesulfonic acid) [P(CrA-co-AMPS)] (44.22:55.78) copolymer was prepared in N,N-dimethylformamide solution using the benzoyl peroxide (Bz₂O₂) as initiator. Cu(II), Ni(II) and Co(II) chelates of the copolymer were prepared and the formation constants of each complex were determined by the mole-ratio method using UV-vis spectroscopy. UV-vis studies showed that the complex formation tendency increased in the followed order: Cu(II) > Ni(II) > Co(II). The copolymer and its metal chelates were characterized by FTIR, TGA, X-ray diffraction and SEM analysis. Also, in vitro antimicrobial activity of the polymers were tested on various bacteria, and yeast.     

LaSrBO4型复合氧化物的合成及其CO氧化活性研究

LaSrBO4(B=Cu、Ni、 Co、 Fe、 Mn、 Cr ) was studied with respect to their preparation, characteristics and catalytic oxidation activity by means of XRD, XPS, electric conductivity and activity evaluation. Results showed that the calcination temperature has great influence on the formation of the phases of such samples, and was associated with the radius of B ion. The greater the B ion radius, the higher the calcination temperature required for the formation of the phases. It was also found that the activity and the relative content of adsorptive oxygen and lattice oxygen on the sample surf are, the activation energy of electron conduction and the CO oxidation activity may vary with different B ions, and demonstrate a dual-peak pattern with the increase in the number of 3d electrons of the B ion.