• Applied Chemistry for Engineering
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• v.23 no.5
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• pp.510-513
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• 2012

Palladium particles were synthesized by conventional chemical reduction method with ionic liquids. The size and shape of palladium particles were significantly affected by the cation parts of ionic liquids. This is mainly attributed to the different stabilities of the ionic liquid structure formed by the physical bond between the cation parts. Among ionic liquids with [$BF_{4}$] as an anion part, the hexyl substituent in the cation parts was more effective to synthesize palladium particles with the smaller size and more uniform shape.

• Journal of the Korean Chemical Society
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• v.33 no.5
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• pp.530-537
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• 1989

Diethylbenzoylmalonates with various substituents were synthesized in moderately good yields through palladium-catalyzed carbonylative coupling of aryl iodide and diethylmalonate with carbon monoxide. Palladium-catalyzed carbonylative coupling reaction usually proceeded well in polar aprotic solvents in the presence of three equivalents of inorganic bases and palladium(II) catalyst. When the reaction was carried out under 10 atm pressure of carbon monoxide, the yield of diethylbenzoylmalonate derivatives was much better than that of reaction under atomspheric pressure of carbon monoxide.

• Journal of the Korean Society of Mineral and Energy Resources Engineers
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• v.56 no.4
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• pp.359-366
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• 2019

This article aims to summarize the recycling status of scrap gold, silver, platinum, and palladium by regions and industries in order to utilize the data for securing raw materials of the domestic urban mining industry. The amount of gold from scrap has shown a tendency to decrease in countries other than China over the last ten years, which is attributed to the increase in scrap containing gold in China. The industry demand for gold is the highest in electronic products, but it is decreasing. The amount of scrap recycling for silver has declined but total silver production has increased by increasing mine products. As production and demand from platinum and palladium scrap are mostly for catalysts, their demand could be affected by the electric vehicle industry.

• Journal of the Korean Chemical Society
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• v.29 no.5
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• pp.490-495
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• 1985

Novel palladium (II) complexes, $[Pd((ieaa)_2-en)]$ and [PdCl((ieaa)-l-pn)] ($(ieaa)_2-en)]$ and (ieaa)-l-pn denote N,N'-ethylenebis(isonitrosoethylacetoacetate imine) and l-N-(2-aminopropyl)-isonitrosoethylacetoacetate imine, respectively), have been prepared. The palladium (II) complexes were characterized on the bases of the electronic absorption, circular dichroism (CD), $^{13}C$ NMR, infrared, and Raman spectra. The reaction of palladium(II) cliloride and isonitrosoethylacetoacetate (ieaa) with methylenediamine gives an $(ieaa)_2-en)]$ type Schiff base, while similar reaction using l-propylenediamine instead of ethylenediamine gives an (ieaa)-l-pn type Schiff base. The difference in formation is discussed from the stereochemical viewpoint of the diamine employed.

• Journal of the Korean Chemical Society
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• v.15 no.4
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• pp.191-197
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• 1971

Ruthenium content in highly purified palladium metal (99.9%) was determined by counting $^{105}Rh$ nuclide which was produced by $^{104}Ru(n,{\gamma};{\beta}^-)^{105}Rh$ nuclear reaction. Palladium sample and ruthenium standard were irradiated by neutron with the Pneumatic Transfer System of TRIGA MARK II reactor. Palladium and ruthenium were dissolved by treating with aqua-regia and by fusing with sodium peroxide flux respectively. $^{105}Rh$ was separated through anion and cation exchange resin columns. The ruthenium content was determined by comparing the $^{105}Rh$ activities, obtained from the palladium sample, with that from pure ruthenium standard. The detection limit of ruthenium by the present method is about 1 ppm of ruthenium in 10 mg of palladium, which is approximately 40 times more sensitive than that of the conventional radioactivation method which employs $^{102}Ru(n,{\gamma})^{103}Ru$ nuclear reaction.

• Resources Recycling
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• v.26 no.3
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• pp.26-31
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• 2017

LIX 63 showed a selectivity for the extraction of Pd(II) over other PGMs, such as Pt(IV), Ir(IV) and Rh(III) from 6 M HCl solution. Moreover, HCl solution has significant effect on the oxidation-reduction reaction between Ir(IV) and LIX 63. Therefore, the applicability of employing LIX 63 for the separation of the 4 PGMs was investigated from 3 M HCl solution. From 3 M HCl solution, only Pd(II) was selectively extracted by LIX 63 and its extraction percentage was higher than from 6 M HCl solution. Extraction of the Pd(II) free raffinate with TBP led to the selective extraction of Pt(IV). After oxidation of Ir(III) with $NaClO_3$ to Ir(IV), extraction of the Pt(IV) free raffinate with Aliquat 336 selectively extracted Ir(IV). For each extraction step, optimum stripping conditions were obtained. By this process, it was possible to separate the 4 PGMs by solvent extraction from 3 M HCl solution.

• Journal of the Korean Chemical Society
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• v.37 no.4
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• pp.423-430
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• 1993

New Palladium(0)-olefin complexes, $(PMe_3)_2Pd{CH_2=C(CH_3)COOH} \;and\;(PMe_3)_2Pd{(CH_3)CH=CHCOOH}$ have been prepared by treating $Pd(PMe_3)_2$(styrene) with methacrylic acid and trans-crotonic acid, respectively. These complexes were characterized by elemental analysis, IR and $^1H-,\;^{13}C-,\;and\;^{31}P$-NMR spectroscopy. The carboxylic acid entity was found non-bonded with palladium while ${\pi}$-bond is formed between the olefin double bond and Pd(0). The results are compared with the metallacycle formation the reaction of Pd(PMe3)2(styrene) with 3-butenoic acid.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.9
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• pp.2197-2202
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• 2014

In this paper, we report on an investigation of highly sensitive sensing performance of a hydrogen sensor composed of palladium (Pd) nanowires. The Pd nanowires have been grown by electrodeposition into nanochannels and liberated from the anodic aluminum oxide (AAO) template by dissolving in an aqueous solution of NaOH. A combination of photo-lithography, electron beam lithography and a lift-off process has been utilized to fabricate the sensor using the Pd nanowire. The hydrogen concentrations for 2% and 0.1% were obtained from the sensitivities (${\Delta}R/R$) for 1.92% and 0.18%, respectively. The resistance of the Pd nanowires depends on absorption and desorption of hydrogen. Therefore, we expect that the Pd nanowires can be applicable for detecting highly sensitive hydrogen gas at room temperature.

• Resources Recycling
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• v.18 no.1
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• pp.30-37
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• 2009

Distribution diagram of Pt(IV), Pd(II), and Rh(III) in HCl solution was obtained as a function of HCl concentration from 0.001 to 10 M by considering complex formation reaction together with mass balance. When HCl concentration was higher than 0.1 M, most of Pt and Pd in HCl solution exist as $PtCl_6^{2-}$ and $PtCl_4^{2-}$. The concentration of HCl had a feat effect on the speciation of Rh(III). As HCl concentration increases from 0.1 to 10 M, the pedominant species changes from $PhCl_5^{2-}$ to $PhCl_6^{3-}$. Interaction parameters of $PtCl_6^{2-}$ and $PdCl_4^{2-}$ with hydrogen ion were evaluated from the solvent extraction data of Pt and Pd reported in the literature.

• Applied Chemistry for Engineering
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• v.16 no.2
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• pp.282-287
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• 2005

Palladium membranes, which are permselective to hydrogen separation, were used for the hydrogen purification and in membrane reactors for improving conversions by shifting the reaction equilibrium. Palladium/ceramic composite membranes were prepared by electroless plating technique and then etched in titanium chloride ($TiCl_4$) as a post treatment to enhance the membrane's durability. These membranes were used for membrane reactors in water gas shift (WGS) reaction. CO conversions for the membrane reactor were obtained according to experimental parameters and compared to the traditional reactor without a palladium/ceramic membrane. As a result, CO conversion using palladium membrane reactor at an appropriate condition was over 20~25% greater than that without the membrane reactor. The stability in the long-term test of up to 120 h for WGS reaction with the membrane reactor was good without the degredation of CO conversion.