PVP-蒙脱土双负载Pd-Sn催化剂催化芳香卤化物水相脱卤

负载型双金属催化剂 ,由于双金属的协同作用 ,使催化活性明显提高 .因而负载型双金属催化剂用于催化有机反应 ,已成为人们研究的热点 .高聚物负载双金属催化剂催化有机卤化物脱卤已有报道[1～ 3] ,但脱卤反应大多在有机相中进行 ,若在水相中 ,催化剂则失去活性[2 ] ,且不易回收和重复使用 .然而有毒的卤化物常存在于化工、印染等工业排放的废水中 ,这些废水流入江、河、湖、海或渗漏在地下 ,造成对水体的严重污染 .为消除废水中有机卤化物对环境的污染 ,我们将 PVP(聚乙烯吡咯烷酮 )负载双金属后再负载到无机载体蒙脱土( Mont K1 0 )上 ,…     

双负载双金属催化剂催化芳香卤化物水相脱卤的研究

用PVP（聚乙烯吡咯烷酮）配合双金属Pd—Mn后,再负载于PEG400（平均分子量为400的聚乙二醇）官能化的高岭土上,制成双负载双金属催化剂PVP—PdCl2-MnCl2／GLM—PECA00,用于催化不溶于水的芳香卤化物水相脱卤,对芳香氯化物呈现出高的脱氯活性,重复使用六次转化率仍可达到62．14％,通过IR,TEM,XPS的表征对催化剂各组分在催化脱卤中的作用进行了探讨．     

官能化蒙脱土负载双金属催化芳香氯化物水相脱氯

用PVP(聚乙烯吡咯烷酮)络合双金属Pd^2 ,Sn^4 后，再负载于用PEG400(平均分子量为400的聚乙二醇)官能化的蒙脱土上，制成双金属催化剂PVP—PdCl2-SnCl4/Montk10-PEG400,用于催化难溶于水的芳香卤化物水相脱卤，芳香族氮化物转化率达100％，该催化剂可重复使用。对催化剂进行了IR及TEM表征。     

PVP-PdCl2-CuCl2/SiO2-PEG600催化芳氯化物水相脱氯研究

PVP(聚乙烯吡咯烷酮)负载双金属催化剂催化芳香氯化物脱氯已有报道[1～3];利用双金属的协同作用,可以大大提高催化剂的脱氯活性和选择性[4]. 但是,这些研究多是在有机相中进行的,催化剂在水相中则会降低甚至失去活性,且难以回收和重复利用. 然而,难溶于水的有毒芳香氯化物,常存在于工业或生活排放的废水中. 由于治理环境的需要,研究芳香氯化物催化水相脱氯,则是极具挑战性的课题. 本文把起相转移作用的聚乙二醇(PEG)键合到硅胶上作为固相载体,制成双负载双金属水相脱氯催化剂PVP-PdCl2-CuCl2/SiO2-PEG600,成功地用于难溶于水的芳香氯化物的水相脱氯. 研究结果表明,这种催化剂对于芳香氯化物有良好的催化脱氯性能,使用中便于分离并能重复利用. 同时,用IR,TEM和XPS等手段对催化剂进行了表征,探讨了催化剂中各组分在催化脱氯中的作用.     

Dechlorination of Aromatic Chlorides in Aqueous System Catalyzed by Functionalized MontK10 Supported Palladium—tin

A novel bisupporter binetal catalyst PVP-PdCl2-SnCl4/MonK10-PEG400,using for dehalogenation of insoluable aromatic halides in aqueous system,has shown high dechlorination activity and selectivity,without any organic solvent or phase transfer catalyst.The conversion of aromatic chlorides can reach 100%.The catalyst is easy to prepare and has good reusability.     

XiDehalogenation of Aryl Halides Catalyzed by MontK10 Immobilized PVP-Pd-Sn Catalyst in Aqueous System

Catalytic dehalogenation of organic halides is of great value to the organic synthesis and for the preventing of environmental pollution. Although, in recent years, there are many reports describing dehalogenation of organic halides in the literature1,2,3, most of them were carried out in the organic system,only few examples4,5 of dehalogenation were carried out in aqueous system. The toxic aryl halides may contaminate and harm human being seriously through food chain. Therefore, it is of utmo…     

Dehalogenation of Aryl Halides Catalyzed by Montmorillonite Immobilized Bimetal Catalyst in Aqueous System

A novel bisupported bimetal catalyst PVP-PdCl2-FeSO4/Al-Mont-PEG600 was prepared by immobilization of PVP (poly (N-vinyl-2-pyrrolidone)) supported bimetallic catalyst using alumina pillared inartificial montmorillonite as the carrier. This catalyst has good dehalogenation activity and selectivity to aryl halides-o-chlorotoluene in aqueous system in the presence of phase transfer catalyst (PEG) and sodium formate as hydrogen source. The catalyst also shows good reusability.     

Study on PEG-（NH4）2SO4 Aqueous Two-Phase System and Distribution Behavior of Drugs

The distribution behavior of chlorpromazine hydrochloride (CPZ), procaine hydrochloride (PCN) and procaine amide hydrochloride (PCNA) in polyethylene glycol (PEG800 or PEG1500)-(NH4)2SO4 aqueous two-phase systems has been investigated. The result shows that the PEG-(NH4)2SO4 aqueous two-phase system has potential extraction capability in small molecular drug separation. In PEG800-(NH4)2SO4 system, the extraction efficiencies (E) of CPZ, PCN and PCNA amount to 92.8%, 74.5% and 74.4%, respectively, with the distribution coefficients (KD) being 25.7, 5.9 and 5.8, correspondingly. In PEG1500-(NH4)2SO4 system, the extraction efficiencies (E) of CPZ,PCN and PCNA are 93.7%, 71.3% and 63.2%, respectively, with distribution coefficients (KD) of 39.6, 6.6 and 5.0,correspondingly. Based on the study on ultraviolet and fluorescence spectra and also distribution behavior of the drugs in PEG-(NH4)2SO4 aqueous two-phase system, extraction mechanism was further proposed that both hydrogen bond and hydrophobic interaction are involved in extraction.     

Synthesis and reactivity of para-substituted benzoylmethyltellurium(II and IV) compounds: observation of intermolecular C-H-O hydrogen bonding in the crystal structure of (p-MeOC6H4COCH2)2TeBr2

Bis(p-substituted benzoylmethyl)tellurium dibromides, (p-YC₆H₄COCH₂)₂TeBr₂, (Y=H (1a), Me (1b), MeO (1c)) can be prepared either by direct insertion of elemental Te across C_Rf-Br bonds (where C_Rf refers to α-carbon of a functionalized organic moiety) or by the oxidative addition of bromine to (p-YC₆H₄COCH₂)₂Te (Y=H (2a), Me (2b), MeO (2c)). Bis(p-substituted benzoylmethyl)tellurium dichlorides, (p-YC₆H₄COCH₂)₂TeCl₂ (Y=H (3a), Me (3b), MeO (3c)), are prepared by the reaction of the bis(p-substituted benzoylmethyl)tellurides 2a-c with SO₂Cl₂, whereas the corresponding diiodides (p-YC₆H₄COCH₂)₂TeI₂ (Y=H (4a), Me (4b), MeO (4c)) can be obtained by the metathetical reaction of 1a-c with KI, or alternatively, by the oxidative addition of iodine to 2a-c. The reaction of 2a-c with allyl bromide affords the diorganotellurium dibromides 1a-c, rather than the expected triorganotelluronium bromides. Compounds 1-4 were characterized by elemental analyses, IR spectroscopy, ¹H, ¹³C and ¹²⁵Te NMR spectroscopy (solution and solid-state) and in case of 1c also by X-ray crystallography. (p-MeOC₆H₄COCH₂)₂TeBr₂ (1c) provides, a rare example, among organotellurium compounds, of a supramolecular architecture, where C-H-O hydrogen bonds appear to be the non-covalent intermolecular associative force that dominates the crystal packing.     

无机盐存在下双水相体系萃取分离碘-乙基紫-镉(Ⅱ)缔合物

研究了在丙醇-水体系中加入表面活性剂乙基紫(EV)后,影响Cd2 分离的酸度、无机盐、卤离子种类等条件。实验表明,(NH4)2SO4存在下,无表面活性剂EV,一定量的I-,在酸性条件下,Cd2 的萃取率为68%,而同样条件下,加入mg级表面活性剂EV后,Cd2 与EV、г形成三元缔合物,被均相萃取、异相分离;缔合物进入丙醇相,Cd2 被完全萃取分离;在pH 1.0时,试验了Cd2 加入量为5μg/mL时与Fe3 、Co2 、Ni2 、Zn2 、Mn2 、Zn2 、Cr3 的二元或多元离子混合液的分离试验,分离完全。