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1.
本文提出了用二苄基二硫代乙二酰胺(DbDO)为显色剂分光光度测定铑的方法,并进一步研究了该试剂与钯、铂的反应,从而建立了可在一个试样中同时测定该三元素的方法。在2~3mol/L HCl溶液中,钯与DbDO在室温显色,用氯仿萃取并用8.4mol/L HCl振荡有机相,然后在454nm测定。在萃余液中加入SnCl2,并在沸水浴中加热,使铂、铑的DbDO络合物生成,再用氯仿萃取,8.4mol/L HCl  相似文献   

2.
报道了一种对钯离子具有高灵敏度和选择性的新试剂2-(2-噻唑偶氮)-5-[(N,N-二羧基甲基)氨基]苯甲酸(TADCAB)。在0.5mol/LHNO_3介质中,TADCAB与Pd(Ⅱ)形成蓝色配合物,组成为Pd:TADCAB=1:2,最大吸收波长652nm。钯浓度在0~1.4μg/mL范围内符合比耳定律。用双波长法测定,表观摩尔吸光系数ε_(652.0~533.6)=8.2×10 ̄4L·mol ̄(-1)·cm ̄(-1),可以允许大量金属离子共存。所确立的方法无需掩蔽剂和其它分离手段,即可直接用于Pt-Pd催化剂中微量钯的测定,结果满意。  相似文献   

3.
本文报道了以二溴羟基苯基荧光酮(DBH-PF)为指示剂,在阳离子表面活性剂CPC存在下荧光猝灭间接测定Br ̄-的新方法。在0.6mol/LH_2SO_4介质中,Br ̄-和BrO反应生成Br_2,Br_2与DBH-PF(λ_(ex)=495nm,λ_(em)=520nm)生成红色化合物,使体系荧光猝灭。Br ̄-含量在0.25~6.25μg/25mL范围内有良好的线性关系,检测限为0.25μg/25mL。该法灵敏度高,选择性好,用于合成海水样品中Br ̄-的测定,结果满意。  相似文献   

4.
用新合成的偶氮试剂2-(5-硝基-2-吡啶偶氮)-5-二甲氨基苯胺(5-NO_2-PADMA)研究了光度法测定他的反应条件。结果表明,在0.45~1.2mol/L盐酸介质中,钯与试剂形成稳定的蓝色配合物,其最大吸收波长位于621nm处,表观摩尔吸收系数为9.4×10 ̄4L·mol ̄(-1)·cm ̄(-1),配合成的组成为Pd:5-NO_2-PADMA=1:2,钯浓度在0~10μg/10mL范围内符合比尔定律。本方法是目前测定钯的高灵敏度和高选择性体系之一。用于含钯分子筛及二次合金管理样-88中微量钯的测定,结果满意。  相似文献   

5.
本文用Ce(SO_4)_2作氧化剂,在6mol/L HCl溶液中将Sb(Ⅲ)氧化为Sb(Ⅴ),过量的氧化剂用盐酸羟胺还原,生成的[SbCl_6] ̄-与甲基绿形成离子缔合物,在2mol/LHCl溶液中被CHCl_3萃取。Tl、In、Ga、Au等20种离子共存时不干扰测定,用于金属镉及废水中测定微量锑,结果满意。  相似文献   

6.
合成了吡啶-2,6-二甲酸镧钇异核配合物晶体。元素分析结果表明,化学式为LaY(HDPA)_2·(DPA)_2.12H_2O,DPA为吡啶-2,6-二甲酸根。用X射线衍射法测定了配合物的单晶结构,其结构式为[LaY(HDPA)_2(DPA)_2(H_2O)_4」·8H_2O,属单斜晶系,P2_1/a空间群。晶胞参数:a=1.2975(4)nm,b=1.1266(3)nm,c=1.4079(3)nm;β=102;15(2)°,V=2.01190(1)nm ̄3,Z=4,Dc=1.83g/cm ̄3,稀土离子的配位数为9,其配位多面体为扭曲的三冠三角棱柱体。  相似文献   

7.
合成了4种锰(Ⅲ)-苯甲酰丙酮缩乙二胺-有机碱配合物:Mn(bzacen)LClO_4.(L为哌嗪,吡啶,γ-甲基吡啶和乙腈),测定了配合物[Mn(bzacen)(CH_(3)CN)ClO_4]的结构.晶体属正交晶系.空间群P_nma.晶胞参数:a=0.9077(1)nm,b=1.5563(1)nm,c=1.7205(2)nm,V=2.4305nm ̄3,Z=4,D_c=1.48g/cm ̄3,D_m=1.49g/cm ̄3.配合物呈拉长八面体结构.对配合物的电子光谱和红外光谱进行了归属.  相似文献   

8.
贵金属同时浮选分离富集行为的研究及ICP-AES的测定   总被引:3,自引:0,他引:3  
本文通过对贵金属-碘化钾-孔雀绿显色体系的浮选行为研究,建立了一种同时浮选富集分离铂、钯、铑、铱、金的新方法。实验结果表明,在0.36mol/LHCl0.1mol/LKI和2.4×10 ̄(-4)mol/LMG的溶液中,加入环已烷振荡1min,铂、钯、铑、铱、金可被定量浮选,继而用ICP-AES测定。对含量为5~150μg的贵金属,浮选回收率分别为铂88.6%~95.7%,钯92.3%~99.5%,铑93.7%~101%,铱92%~98.5%,金86.4%~94%。方法应用于铜镍矿、铂网废料等物料中上述贵金属元素的测定,结果满意。  相似文献   

9.
三羰基环戊二烯基钼负离子与1,3-二卤丙烷在一缩二乙二醇二甲醚介质中反应,生成环卡宾配合物CpMoX(CO)_2CO(CH_2)_2CH2(X=Br,I).硅桥连双环戊二烯基三羰基钼负离子与1,3-二卤丙烷顺利地进行类似反应,生成相应的硅桥连双[环卡宾钼配合物]──E[C_5H_4MoX(CO)_2]CO(CH_2)_2CH_2]_2(E=Me_2Si,Me2SiSiMe_2,Me2SiOSiMe_2).化合物硅氧硅桥联二茂二钼环卡宾配合物11的晶体结构经X射线衍射测定,晶体属三斜晶系,P1空间群,晶体学数据:a=0.8188(1)nm,b=1.045(3)nm,c=2.3252(4)nm,α=94.14(2)°,β=94.09(1)°,γ=102.48(2)°,V=1.9306nm ̄3,Z=2,D_c=1.854g/cm ̄3。  相似文献   

10.
高氯酸铒与甘氨酸和丙氨酸配合物的合成及其晶体结构   总被引:1,自引:0,他引:1  
在水溶液中合成了高氯酸铒与甘氨酸和丙氨酸混配配合物[Er_2(Gly)_4)(Ala)_2(H_2O)_4](ClO_4)_6·3H_2O,测定了其单晶结构。晶体属三斜晶系,P1空间群。晶胞参数为a=1.1286(5)nm,b=1244b(2)nm,c=0.9423(2)nm,a=77.63(2)°,β=7527(2)°,γ=64.45(2)°,V=1.1466(5)nm ̄3Z=1,D_c=2.154g/cm ̄3。该配合物为链状分子,甘氨酸和丙氨酸的羧基均以桥式与相邻的两个铒离子配位,铒的配位数为8,形成四方反棱柱型配位多面体。  相似文献   

11.
本文报道了以新试剂2-(5-硝基-2吡啶偶氮)-5-二甲氨基苯胺(5-NO_2-PADMA)作分光光度法测定铑的新体系.结果表明,在 PH=5.25~6.75范围内,铑与 5-NO_2-PADMA形成 1:1的紫红色络合物,其 λ_(max)在 525 nm处,该络合物在 1.8mol/L的盐酸溶液中转变为绿兰色,其最大吸收峰位于620nm处,表观摩尔吸光系数为1.39×10~5L·mol~1·cm~1.反应具有良好的选择性,常见金属离子在一定范围内无干扰.铑含量为0~0.56μg/mL范围内遵守比耳定律.所拟方法操作简便,灵敏度高,用于催化剂中微量铑的测定,结果满意.  相似文献   

12.
Zhao J  Xu Q 《Talanta》1991,38(8):909-912
A simple, rapid and sensitive spectrophotometric method has been developed for the determination of platinum. 5-(4-Nitrophenylazo)-8-(p-toluenesulphonamido)quinoline (NPTSQ) reacts with platinum(II) almost instantaneously in alkaline solution to form a violet-red 1:2 complex with an absorption maximum at 640 nm. Beer's law is obeyed over the concentration range 0-1 mug/ml platinum. The molar absorptivity is 1.37 x 10(5) 1.mole(-1).cm(-1). The method has been used for the determination of microamounts of platinum in catalysts and anode slime.  相似文献   

13.
超微量铂丶铑连续催化极谱测定及其催化波机理的探讨   总被引:3,自引:0,他引:3  
舒柏崇  郑日云 《化学学报》1983,41(5):418-424
For simultaneous determination of ultramicro amounts of platinum and rhodium the optimum condition has been described as 1.5N H2SO4-1.2% NH4Cl-0.0012M (CH2)6N4-0.003% N2H4XH2SO4. Both platinum and rhodium produce hydrogen catalytic waves with peak potential at-1.03 V and - 1.27 V (vs. S. C. E.) and the peak height of differential wave in single-sweep polarograph is directly proportional to the concentration of the metals in the range from 0.05 ppb to 1.0 ppb for platinum and from 0.0025 ppb to 0.1ppb for rhodium, respectively. The influence of other platinum group metals and some base metals on the height of catalytic waves has been examined. It has been shown that the method is very selective. It is applied even at 200:1 or at 1:10 (Pt:Rh). The mechanism of the catalytic waves has been discussed. The catalytic waves of both platinum and rhodium are due to "surface catalytic wave of hydrogen". The wave of rhodium can be attributed to catalytic discharge of hydrogen ion by the complex (Rh(CH2O)2Cl4)-. One of the ligands, formaldehyde, is the product of hydrolysis of hexamethylenetetramine. The wave of plainum can be attributed to catalytic discharge of hydrogen ion by the complex (PtACl5)-, where a denotes intermediate product (a substance containing CH2=N group) formed during the hydrolysis of hexamethylenetetramine. The role of hydrazine sulfate in catalytic system has been shown. Hydzazine can react with formaldehyde to from (CH2=N)2 which promotes the growth of platinum catalytic wave and in this way the concentration of formaldehyde in the system can be controlled.  相似文献   

14.
Two sensitive, precise spectrophotometric methods for the determination of rhodium with malachite green are proposed. The anionic rhodium complex with tin(II) chloride yields an ion associate with malachite green; on shaking the solution (in 6.5 M HCl) with benzene, the sparingly soluble ion associate (rhodium: malachite green =1:2) precipitates at the phase boundary. The precipitate is dissolved in a mixture of acetone and water (3 + 1). The molar absorptivity is 1.44 × 105 l moll-1 cm-1 at 627 nm. When test solutions (0.65 M HCl) are shaken with diisopropyl ether, an ion associate of a different composition is formed (rhodium :malachite green = 1:5) and the molar absorptivity is 3.4 × 105 l mol-1 cm-1. Platinum, palladium and iridium interfere except in small amounts.  相似文献   

15.
Kundu D  Roy SK 《Talanta》1992,39(4):415-418
A spectrophotometric method has been developed for determination of trace amounts of platinum in glass. The method is based on the extraction of platinum(II) from 1M hydrochloric acid containing 0.2M stannous chloride and 4 x 10(-4)M dithizone onto polyurethane foam, elution with acetone (containing 3% v/v concentrated hydrochloric acid) and measurement of the absorbance of the eluate at 530 nm. Beer's law is obeyed up to 10.0 microg/ml Pt. The minimum platinum level in the eluate that can be determined by this method is 0.1 microg/ml.  相似文献   

16.
Brajter K  Kleyny K  Vorbrodt Z 《Talanta》1980,27(5):433-435
It has been established that, owing to the amphoteric properties of rhodium(III) hydroxide, by making a rhodium chloride solution alkaline (pH approximately 13) with sodium hydroxide and then acidifying to pH 2 with nitric acid it is possible to convert at least 99% of the rhodium into cationic forms. This fact is utilized for separation of rhodium(III) and platinum(IV) from chloride solutions on a sulphonic acid cation-exchanger in hydrogen form. Loss of rhodium in the separation process is < 1%. Platinum elution is complete. This method is suitable for separation of mixtures of rhodium and platinum (present in molar ratio between 1:200 and 20:1).  相似文献   

17.
El-Ghamry MT  Frei RW 《Talanta》1969,16(2):235-243
A simple, rapid, reproducible, sensitive and selective method is proposed for the spectrophotometric determination of submicrogram amounts of platinum(IV) in aqueous media. The proposed method involves the formation of a ternary complex between the hexa-ammine-platinum(IV) cationic complex, and the counter-ion 2,4,5,7-tetrabromofluorescein ethyl ester. The reaction is instantaneous and the red ternary complex remains stable for ca. 1 hr. Beer's law is obeyed over the range 39-1170 ppM with molar absorptivity of ca. 8.0 x 10(4) at 555 nm and pH 10. A relative standard deviation of 1.1% was found for the reproducibility of the method. Even without the use of masking agents, no interference is encountered from other noble metals except rhodium(III). Of 13 other cations and 8 anions tested, only iron(III) interferes.  相似文献   

18.
Kato K 《Talanta》1977,24(8):503-507
An atomic-absorption spectrophotometric method for the determination of traces of manganese in solution with thenoyltrifluoroacetone (TTA) is described. Manganese(II) is extracted with 0.01M TTA in methyl isobutyl ketone (MIBK) at pH 9.5. The atomic-absorption of the organic phase at 279.5 nm is measured. Except for chromium, iron, hafnium, niobium, nickel, rhodium, tin, titanium and zirconium, microquantities of many other cations and anions do not interfere. Iron can be removed by MIBK extraction before the TTA extraction. The sensitivity of the method was 1.6 ng/ml for 1% absorption in aqueous solution. The method was successfully applied to the analysis of environmental waters. Manganese in the filtered fractions of water samples was reliably determined with relative standard deviations of 7% at the 5 mug/l. level and 1% at 50 mug/l.  相似文献   

19.
Sindhwani SK  Singh RP 《Talanta》1973,20(2):248-251
Acenaphthenequinone monoxime has been found to be a selective reagent for spectrophotometric determination of 1-16 ppm of platinum in the pH range 1.90-3.20. With excess of the reagent, a 1 : 2 (metal : ligand) complex is formed with an absorption maximum at 390 nm and molar absorptivity of 9.0 x 10(3) 1.mole(-1).cm(-1). The effect of foreign ions has been investigated and other platinum metals do not interfere if present in similar amounts to the platinum.  相似文献   

20.
甲壳质、甲壳胺衍生物保护的贵金属胶体   总被引:8,自引:0,他引:8  
<正> 高分子保护金属胶体是近年来金属催化剂领域中引人注目的研究课题。它除了具有负载型金属催化剂的优点外,还具备下列新优点:a.胶体分散体系可形成“均相”溶液;b.保护高分子可以屏蔽胶体催化剂,减小毒物或空气的不良影响;c.胶体溶液的透光性能比颗粒要好得多,由此最近高分子保护金属胶体常被用于光化学研究中的催化剂;d.高分子保护金属胶体与普通金属胶体相比较,不仅具有较稳定的特点,而且尺寸小(1—10nm)、分布窄,表现出极高的催化活性和选择性;e.保护高分子对金属的修饰作用,可  相似文献   

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