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1.
Breck等[1]发表了用NH4SiF6溶液对分子筛进行脱铝补硅的二次合成方法,提高了骨架的硅铝比,从而改变了分子筛的热稳定性、酸性以及催化活性.作为该方法的扩展,已有将Ti、Te、Cr、Zr、Ga等元素引入分子筛骨架的报道[2~4].目前,已经有杂原子分子筛应用到工业生产中,但采用杂原子分子筛吸附脱硫的报道还较少.前文[5]采用液-固相同晶取代反应制备了骨架含Ga的Y型分子筛,并对其吸附脱硫性能进行了初步研究.本研究进一步对[Ga]AlY的吸附脱硫机理、再生性能等方面进行了深入研究.……  相似文献   

2.
Highly efficient, deep desulfurization of model oil containing dibenzothiophene (DBT), benzothiophene (BT), or 4,6‐dimethyldibenzothiophene (4,6‐DMDBT) has been achieved under mild conditions by using an extraction and catalytic oxidative desulfurization system (ECODS) in which a lanthanide‐containing polyoxometalate Na7H2LnW10O36 ? 32 H2O (LnW10; Ln=Eu, La) acts as catalyst, [bmim]BF4 (bmim=1‐butyl‐3‐methylimidazolium) as extractant, and H2O2 as oxidant. Sulfur removal follows the order DBT>4,6‐DMDBT>BT at 30 ° C. DBT can be completely oxidized to the corresponding sulfone in 25 min under mild conditions, and the LaW10/[bmim]BF4 system could be recycled for ten times with only slight decrease in activity. Thus, LaW10 in [bmim]BF4 is one of the most efficient systems for desulfurization using ionic liquids as extractant reported so far.  相似文献   

3.
A series of palladium complexes ( 2a–2g ) ( 2a : [6‐tBu‐2‐PPh2‐C6H3O]PdMe(Py); 2b : [6‐C6F5–2‐PPh2‐C6H3O]PdMe(Py); 2c : [6‐tBu‐2‐PPhtBu‐C6H3O]PdMe(Py); 2d : [2‐PPhtBu‐C6H4O] PdMe(Py); 2e : [6‐SiMe3–2‐PPh2‐C6H3O]PdMe(Py); 2f : [2‐tBu‐6‐(Ph2P=O)‐C6H3O]PdMe(Py); 2g : [6‐SiMe3–2‐(Ph2P=O)‐C6H3S]PdMe(Py)) bearing phosphine (oxide)‐(thio) phenolate ligand have been efficiently synthesized and characterized. The solid‐state structures of complexes 2d , 2f and 2g have been further confirmed by single‐crystal X‐ray diffraction, which revealed a square‐planar geometry of palladium center. In the presence of B(C6F5)3, these complexes can be used as catalysts to polymerize norbornene (NB) with relatively high yields, producing vinyl‐addition polymers. Interestingly, 2a /B(C6F5)3 system catalyzed the polymerization of NB in living polymerization manner at high temperature (polydispersity index 1.07, Mn up to 1.5 × 104). The co‐polymerization of NB and polar monomers was also studied using catalysts 2a and 2f . All the obtained co‐polymers could dissolve in common solvent.  相似文献   

4.
An organic‐inorganic material (NH4)2(MimAM)40[Mo132O372(CH3COO)30(H2O)72] have been synthesized by reacting [(NH4)42[MoVI72 MoV60O372(CH3COO)30(H2O)72] with the ionic liquid 3‐Aminoethyl‐1‐methylimidazolium bromide. The catalyst showed remarkably a high catalytic performance in the oxidation of dibenzothiophene (DBT) derivatives with H2O2 35% as a safe and green oxidant. The main parameters affecting the process including catalyst, acid additive, hydrogen peroxide amounts and temperature have been investigated in detail. Sulfur removal of DBT in n‐heptane reached to 98.3% yield at 40 °C using 2.5 mmol H2O2 and 100 mg of (NH4)2(MimAM)40[Mo132O372(CH3COO)30(H2O)72] after 90 min. Under the optimal conditions, BT (benzothiophene), DBT (dibenzothiophene) and 4,6‐DMDBT (4,6‐dimethyl‐dibenzothiophene) achieved high desulfurization efficiency. Our results showed that the reactivity order of different model sulfur compounds are thiophene <4,6‐dimethyl dibenzothiophene< dibenzothiophene. The catalysts could be easily separated from the reaction solution by simple filtration and recycled for several times without loss of activity.  相似文献   

5.
A dibenzothiophene (DBT)-desulfurizing bacteria strain was isolated from oil-contaminated soils and identified as Rhodococcus erythropolis NCC-1. Strain NCC-1 was found to convert DBT to hydroxybiphenyl (2-HBP) via the 4S pathway and also be able to use organic sulfur compounds other than DBT as a sole sulfur source. The strain could desulfurize 4,6-dimethyldibenzothiophene (4,6-DMDBT), which is one of the most recalcitrant dibenzothiophene derivatives to hydrodesulfurization. When two type of oils, a model oil [n-hexadecane (n-C16) containing DBT] and a hydrodesulfurized diesel oil with various organic sulfur compounds, were treated with Rhodococcus erythropolis NCC-1 cells, the total sulfur content significantly decreased, from 150 to 20 mg/L for n-C16 and from 554 to 274 mg/L for diesel oil. The newly isolated strain NCC-1 is considered to have good potential for application in the biodesulfurization of fossil fuels.  相似文献   

6.
In the title compound, [RuII(C10H8N2)3]2[FeIII(CN)6]Cl·8H2O, the [Ru(bpy)3]2+ (bpy is 2,2′‐bi­pyridine) cations and water mol­ecules afford intriguing microporous honeycomb layers, while the [Fe(CN)6]3− anions and the remainder of the water mol­ecules form anionic sheets based on extensive hydrogen‐bonding networks. The cationic and anionic layers alternate along the c axis. The Fe atom in [Fe(CN)6]3− lies on an inversion centre and the axial cyano ligands are hydrogen bonded to the water mol­ecules encapsulated within the micropores [N⋯O = 2.788 (5) Å], giving an unusual interpenetration between the cationic and anionic layers. On the other hand, the in‐plane cyano ligands are relatively weakly hydrogen bonded to the water mol­ecules [N⋯O = 2.855 (7) and 2.881 (8) Å] within the anionic sheets.  相似文献   

7.
The title compound, {(C8H20N)[CdFe(CN)6(C2H8N2)2]·4H2O}n, was isolated from the aqueous system Cd2+/ethyl­ene­diamine (en)/[Fe(CN)6]3− in the presence of [Et4N]Br. The crystal structure is dominated by a one‐dimensional motif, viz. a negatively charged 2,2‐CT (cistrans) [–Cd(en)2—NC—Fe(CN)4—CN–]nn chain. The Cd and Fe atoms of the anion and the N atom of the cation all lie on twofold axes. The ethyl groups of the cation are equally disordered over two orientations. The cationic building block of the chain consists of a CdII atom coordinated by two chelating en ligands, and the distorted octa­hedral coordination is completed by two bridging cyano ligands in cis positions. The anionic building block is an [Fe(CN)6]3− anion in which the FeIII atom is octa­hedrally coordinated by six cyano ligands; two of the cyano ligands, in trans positions, are bridging. The uncoordinated water mol­ecules link neighbouring chains through O—H⋯N and N—H⋯O hydrogen bonds.  相似文献   

8.
The reaction of the donor‐functionalised N,N‐bis(2‐{pyrid‐2‐yl}ethyl)hydroxylamine and [LnCp3] (Cp=cyclopentadiene) resulted in the formation of bis(cyclopentadienyl) hydroxylaminato rare‐earth metal complexes of the general constitution [Ln(C5H5)2{ON(C2H4o‐Py)2}] (Py= pyridyl) with Ln=Lu ( 1 ), Y ( 2 ), Ho ( 3 ), Sm ( 4 ), Nd ( 5 ), Pr ( 6 ), La ( 7 ). These compounds were characterised by elemental analysis, mass spectrometry, NMR spectroscopy (for compounds 1 , 2 , 4 and 7 ) and single‐crystal X‐ray diffraction experiments. The complexes exhibit three different aggregation modes and binding motifs in the solid state. The late rare‐earth metal atoms (Lu, Y, Ho and Sm) form monomeric complexes of the formula [Ln(C5H5)22‐ON(C2H4‐η1o‐Py)(C2H4o‐Py)}] ( 1 – 4 , respectively), in which one of the pyridyl nitrogen donor atoms is bonded to the metal atom in addition to the side‐on coordinating hydroxylaminato unit. The larger Nd3+ and Pr3+ ions in 5 and 6 make the hydroxylaminato unit capable of dimerising through the oxygen atoms. This leads to the dimeric complexes [(Ln(C5H5)2{μ‐η12‐ON(C2H4o‐Py)2})2] without metal–pyridine bonds. Compound 7 exhibits a dimeric coordination mode similar to the complexes 5 and 6 , but, in addition, two pyridyl functions coordinate to the lanthanum atoms leading to the [(La(C5H5)2{ON(C2H4o‐Py)}{μ‐η12‐ON(C2H4‐η1o‐Py)})2] complex. The aggregation trend is directly related to the size of the metal ions. The complexes with coordinative pyridine–metal bonds show highly dynamic behaviour in solution. The two pyridine nitrogen atoms rapidly change their coordination to the metal atom at ambient temperature. Variable‐temperature (VT) NMR experiments showed that this dynamic exchange can be frozen on the NMR timescale.  相似文献   

9.
The title compound, (C3H5N2)2[Fe(CN)5(C3H4N2)], is composed of a mononuclear [Fe(CN)5(pyrazole)]2− dianion and two 1H‐pyrazol‐2‐ium cations. A three‐dimensional supramolecular network is formed through a rich scheme of N—H...N hydrogen bonds and C—H...π interactions among the cations and anions.  相似文献   

10.
In the title compound, poly[[triaqua{μ4‐2‐[4,6‐bis(carboxymethylsulfanyl)‐1,3,5‐triazin‐2‐ylsulfanyl]acetato}{μ2‐2‐[4,6‐bis(carboxymethylsulfanyl)‐1,3,5‐triazin‐2‐ylsulfanyl]acetato}barium(II)] monohydrate], {[Ba(C9H8N3O6S3)2(H2O)3]·H2O}n, each BaII atom is nine‐coordinated by six O atoms from carboxylate groups of four different 2‐[4,6‐bis(carboxymethylsulfanyl)‐1,3,5‐triazin‐2‐ylsulfanyl]acetate ligands and three O atoms from water molecules. The triazine ligand is partially deprotonated, as verified by intermolecular hydrogen‐bonding parameters, and adopts μ2‐η11 and μ4‐η112 coordination modes to connect the BaII centres, forming a novel double‐layered structure. Topological analysis indicates that the whole structure is a novel (4,6)‐connected net, considering the ligands and BaII centres as four‐ and six‐connected nodes, respectively.  相似文献   

11.
The title compound, (C16H38N4)[Fe(CN)5(NO)]·2H2O, contains one [Fe(CN)5(NO)]2− dianion, two half [H2teta]2+ dications (teta is 5,7,7,12,14,14‐hexa­methyl‐1,4,8,11‐tetra­aza­cyclo­tetra­decane), each lying about an independent inversion centre, and two solvent water mol­ecules, all of which are held together by hydrogen bonds to form a three‐dimensional supramolecular framework.  相似文献   

12.
Reactions of the open‐cage fullerene C63NO2(Py)(Ph)2 ( 1 ) with [Ru3(CO)12] produce [Ru3(CO)8(μ,η5‐C63NO2(Py)(Ph)2)] ( 2 ), [Ru2H(CO)3(μ,η7‐C63N(Py)(Ph)(C6H4))] ( 3 ), and [Ru(CO)(Py)2(η3‐C63NO2(Py)(Ph)2)] ( 4 ), in which the orifice sizes are modified from 12 to 8, 11, and 15‐membered ring, through ruthenium‐mediated C?O and C?C bond activation and formation.  相似文献   

13.
It is urgent to develop a new deep desulfurization process of fuels as the environmental pollution increases seriously. In this work, a series of Lewis acidic ionic liquids (ILs) [C43MPy]Cl/nZnCl2 (n=1, 1.5, 2, 3) were synthesized and used in extraction and catalytic oxidative desulfurization (ECOD) of the fuels. The effects of the Lewis acidity of ILs, the molar ratio of H2O2/sulfur, temperatures, and different substrates including dibenzothiophene (DBT), benzothiophene (BT) and thiophene (TS), on sulfur removal were investigated. The results indicated that [C43MPy]Cl/3ZnCl2 presented near 100% DBT removal of model oil under conditions of 323 K, H2O2/DBT molar ratio 6:1. Kinetics for the removal of DBT, BT and TS by the [C43MPy]Cl/3ZnCl2-H2O2 system at 323 K is first-order with the apparent rate constants of 1.1348, 0.2226 and 0.0609 h-1, and the calculated apparent activation energies for DBT, BT and TS were 61.13, 60.66, and 68.14 kJ/mol from 298 to 308 K, respectively. After six cycles of the regenerated [CC43MPy]Cl/3ZnCl2, the sulfur removal had a slight decrease. [CC43MPy]Cl/3ZnCl2 showed a good desulfurization performance under optimal conditions.  相似文献   

14.
The bimetallic title complex, [CuFe(CN)5(C12H30N6O2)(NO)] or [Cu(L)Fe(CN)5(NO)] [where L is 1,8‐bis(2‐hydroxy­ethyl)‐1,3,6,8,10,13‐hexa­aza­cyclo­tetra­decane], has a one‐dimensional zigzag polymeric –Cu(L)–NC–Fe(NO)(CN)3–CN–Cu(L)– chain, in which the CuII and FeII centres are linked by two CN groups. In the complex, the CuII ion is coordinated by four N atoms from the L ligand [Cu—N(L) = 1.999 (2)–2.016 (2) Å] and two cyanide N atoms [Cu—N = 2.383 (2) and 2.902 (3) Å], and has an elongated octahedral geometry. The FeII centre is in a distorted octahedral environment, with Fe—N(nitroso) = 1.656 (2) Å and Fe—C(CN) = 1.938 (3)–1.948 (3) Å. The one‐dimensional zigzag chains are linked to form a three‐dimensional network via N—H⋯N and O—H⋯N hydrogen bonds.  相似文献   

15.
《Electroanalysis》2006,18(16):1627-1630
The surface of a gold (Au) electrode was coated with layer‐by‐layer (LbL) thin films composed of poly(vinyl sulfate) (PVS) and different type of poly(amine)s including poly(allylamine) (PAH), poly(ethyleneimine) (PEI) and poly(diallyldimethylammonium chloride) (PDDA) and redox properties of ferricyanide ion ([Fe(CN)6]3?) on the LbL film‐coated Au electrodes were studied. The LbL film‐coated electrodes exhibited redox response to [Fe(CN)6]3? ion when the outermost surface of the LbL film was covered with the cationic poly(amine)s while virtually no response was observed on the LbL film‐coated electrodes whose outermost surface was covered with PVS due to an electrostatic repulsion between [Fe(CN)6]3? ion and the negatively‐charged PVS layer. The redox properties of [Fe(CN)6]3? ion on the LbL film‐coated electrodes significantly depended on the type of polycationic materials in the LbL film. The LbL film‐coated electrodes which had been immersed in the [Fe(CN)6]3? solution for 15 min exhibited redox response even in a [Fe(CN)6]3? ion‐free buffer solution, suggesting that [Fe(CN)6]3? ion is confined in the films. In the buffer solution, redox peaks were observed between +0.1 and 0.4 V depending on the type of polycations in the film. Thus, [Fe(CN)6]3? ion can be confined in the film and the redox potential is polycation‐dependent.  相似文献   

16.
The title compound, tetra­ethyl­ammonium dodeca‐μ‐cyano‐hexa­cyano­tetrakis­(ethyl­ene­di­amine)­tetra­cadmium(II)­tri­fer­rate(III), (C8H20N)[Cd4Fe3(CN)18(C2H8N2)4], was pre­pared from a reaction mixture containing CdCl2, K3[Fe(CN)6], ethyl­ene­di­amine (en) and [Et4N]Br in a 1:1:3:1 molar ratio. The crystal structure consists of a negatively charged three‐dimensional framework of {[Cd(en)]4[Fe(CN)6]3} anions, with [Et4N]+ cations located in the cavities of the framework. The Cd atom is octahedrally coordinated by one disordered chelating en mol­ecule [mean Cd—N = 2.35 (3) Å] and four N‐­bonded bridging cyano groups [Cd—N distances are in the range 2.283 (2)–2.441 (2) Å]. There are two crystallographically independent [Fe(CN)6]3− anions in the structure and in each the Fe atom lies on a twofold axis. In the first [mean Fe—C = 1.941 (5) Å], all the cyano groups are bridging ligands, while in the second [mean Fe—C = 1.945 (2) Å], there are two terminal cyano ligands in trans positions. The Cd—N—C angles range from 128.6 (2) to 172.8 (2)°.  相似文献   

17.
The new high‐spin iron(II) complex, [Fe(C12H10N6)2(H2O)2](C8H3N4S)2 or [Fe(abpt)2(H2O)2](tcnsme)2 [where abpt is 4‐amino‐3,5‐di‐2‐pyridyl‐4H‐1,2,4‐triazole and tcnsme is the 1,1,3,3‐tetracyano‐2‐methylthiopropenide anion], consists of discrete [Fe(abpt)2(H2O)2]2+ dications, where the FeII ion is coordinated by two N,N′‐bidentate chelating abpt ligands in the equatorial plane and two water molecules in trans positions, generating a distorted octahedral [FeN4O2] environment. The cationic unit is neutralized by two polynitrile tcnsme anions, in which the C—N, C—C and C—S bond lengths indicate extensive electronic delocalization. In the crystal structure, the dications and anions are linked through O—H...N and N—H...N hydrogen bonds involving the water H atoms and those of the NH2 groups and the N atoms of the CN groups, leading to the formation of a three‐dimensional network.  相似文献   

18.
Using the tricyanometalate building block, (nBu4N)[(Tp*)Fe(CN)3] [Bu4N+ = tetrabutylammonium cation; Tp* = hydrotris(3,5‐dimethylpyrazol‐1‐yl)borate], and bidentate Schiff base ligands, HL1 or HL2 {HL1 = 2‐[[(2‐phenylethyl)imino]methyl]phenol; HL2 = 4‐methoxy‐2‐[[(2‐phenylethyl)imino]methyl]phenol}, two heterobimetallic one‐dimensional (1D) chain complexes, [Mn(L1)2Fe(Tp*)(CN)3]n ( 1 ) and [Mn(L2)2Fe(Tp*)(CN)3]n ( 2 ), were synthesized. Single crystal X‐ray diffraction reveal the formation of neutral cyano‐bridged zigzag single chains in 1 and 2 . Magnetic studies demonstrate that both complexes show ferromagnetic interactions between central FeIII and MnIII atoms.  相似文献   

19.
Reactions of magnesium 3‐tert‐butyl‐8‐R‐4‐oxo‐4H‐pyrazolo[5,1‐c][1,2,4]triazin‐1‐ides (R = CN, CO2Et) with AlkMgBr led to nucleophilic additions to either side chain or triazine core, with selectivity being dependent on the nature of substituents, as well as on the solvents used. Previously inaccessible C8‐functionalized and C4‐functionalized pyrazolo[5,1‐c][1,2,4]triazines and 3‐tert‐butyl‐3‐ethyl‐4‐oxo‐1,2,3,4‐tetrahydropyrazolo[5,1‐c][1,2,4]triazine were synthesized, and their reactivity and spectral data discussed.  相似文献   

20.
[LCRP((PhP)2C2H4)][OTf] ( 4 a,b [OTf]) and [LCiPrP(PPh2)2][OTf] ( 5 b [OTf]) were prepared from the reaction of imidazoliumyl‐substituted dipyrazolylphosphane triflate salts [LCRP(pyr)2][OTf] ( 3 a,b [OTf]; a : R=Me, b =iPr; LCR=1,3‐dialkyl‐4,5‐dimethylimidazol‐2‐yl; pyr=3,5‐dimethylpyrazol‐1‐yl) with the secondary phosphanes PhP(H)C2H4P(H)Ph) and Ph2PH. A stepwise double P?N/P?P bond metathesis to catena‐tetraphosphane‐2,3‐diium triflate salt [(Ph2P)2(LCMeP)2][OTf]2 ( 7 a [OTf]2) is observed when reacting 3 a [OTf] with diphosphane P2Ph4. The coordination ability of 5 b [OTf] was probed with selected coinage metal salts [Cu(CH3CN)4]OTf, AgOTf and AuCl(tht) (tht=tetrahydrothiophene). For AuCl(tht), the helical complex [{(Ph2PPLCiPr)Au}4][OTf]4 ( 9 [OTf]4) was unexpectedly formed as a result of a chloride‐induced P?P bond cleavage. The weakly coordinating triflate anion enables the formation of the expected copper(I) and silver(I) complexes [( 5 b )M(CH3CN)3][OTf]2 (M=Cu, Ag) ( 10 [OTf]2, 11 [OTf]2).  相似文献   

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