Traces Of Ruthenium Research Articles

Trace ruthenium dioxide stabilize active center of CoFe-LDH for efficient water electrolysis

It is immensely meaningful to design efficient electrolysis for water electrolysis and realize green hydrogen production. Herein, a ruthenium dioxide modified CoFe-Layered double hydroxides (LDHs) catalyst (RuO2/CoFe-LDH/NF) was synthesized by combining the advantages of RuO2 and CoFe-LDHs for driving alkaline water and seawater. RuO2/CoFe-LDH/NF display impressive activity and stability at 10 mA cm−2, which only need an overpotential of 59 and 270 mV for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) respectively. Meaningfully, the catalyst only required a small cell voltage of 1.58 V as a bifunctional catalyst, what is superior to commercial RuO2/NF||Pt/C/NF (1.66 V). In addition, RuO2/CoFe-LDH/NF exhibited excellent HER and OER performance with overpotentials of 119 and 260 mv in alkaline seawater at 10 mA cm−2, respectively. Additionally, RuO2/CoFe-LDH/NF displays a larger corrosion potential, smaller corrosion and improved oxygen evolution capacity than CoFe-LDH/NF. Moreover, there is electron transfer between Ru and Co or Fe, which can improve the micro-coordination environment and enhance the stability for RuO2/CoFe-LDH/NF. The method with integration of RuO2 and CoFe-LDH could be broadened to explore other robust bifunctional catalysts for water/seawater electrolysis.

Trace ruthenium promoted dual-reconstruction of CoFeP@C/NF for activating overall water splitting performance beyond precious-metals

Trace ruthenium promoted dual-reconstruction of CoFeP@C/NF for activating overall water splitting performance beyond precious-metals

Integrating trace ruthenium cluster with cobalt boride toward superior overall water splitting in neutral media

Cobalt boride which is an active bifunctional water splitting catalyst in alkaline media shows poor activity in neutral media. We found that trace ruthenium (Ru) cluster deposition (80 μg·cm−2) on cobalt boride by simple wet chemical reduction method can dramatically improve both its hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) activity in neutral solution. The electron transfer from Co-B to Ru may result in the easier water dissociation step so as to facilitate the catalytic process. The resulting Ru@Co-B/Ni binder-free electrode could supply 10 mA cm−2 at overpotentials of 56 mV for HER and 280 mV for OER in 0.5 M phosphate buffer electrolyte. This work proposed a fruitful approach to advance the water splitting performance of transition metal boride in neutral media.

Activation of inert copper for significantly enhanced hydrogen evolution behaviors by trace ruthenium doping

The application of metallic copper in hydrogen evolution reaction (HER) is severely restricted by its low intrinsic activity due to its surface properties that have large energy barriers for water dissociation and weak binding force to H* . Herein, we report an electronic structure engineering strategy to activate the inert Cu for significantly enhanced HER performance by trace doping of Ru (0.70 wt%). Experiments together with theoretical analysis reveal that the Ru dopants attract electrons from the Cu, resulting in the surface with lower energy barriers for the water dissociation process and optimized binding energy with H* . The synthesized Ru doped Cu only involved overpotentials of 33 and 34 mV to reach 10 mA cm-2 in alkali and acid, respectively, together with excellent long-term stability. This work presents an electronic engineering pathway to adjust the electrocatalysis behaviors of metallic copper.

Characteristics of Sr1−xYxTi1−yRuyO3+/−δ and Ru-impregnated Sr1−xYxTiO3+/−δ perovskite catalysts as SOFC anode for methane dry reforming

Dry reforming, a technique to combine methane and carbon dioxide, has received significant attention in efforts to produce synthesis gas (carbon monoxide and hydrogen). These gases can subsequently be used for C1 chemistry applications, and even for high-temperature fuel cell devices. However, suitable electrode materials with highly active and stable properties remain to be found for efficient utilization of a C1 fuel-based fuel cell system. A promising electrode material of yttria-doped strontium titanium oxide with trace ruthenium (Sr0.92Y0.08Ti0.98Ru0.02O3+/−δ; SYTRu) was developed in this work for an efficient and stable dry-reforming catalyst and compared to a Ru-loaded SYT (Ru/SYT) catalyst. The substituted Ru in the former sample was uniformly incorporated (primarily in the atomic level) in the SYT lattice with a perovskite structure. Different Ru species were observed in this case, unlike in the Ru/SYT sample. Ru doping decreased the oxygen vacancy formation energy in calculated by density functional theory and led to a high activity for the surface oxygen. The surface oxygen donating ability to the catalyst was responsible for facilitating the dissociation and decomposition of CH4 and CO2. This led to high conversion efficiency, good syngas selectivity, and stability, along with a small amount of coke formation.

A novel catalytic oxidation process for removing elemental mercury by using diperiodatoargentate(III) in the catalysis of trace ruthenium(III)

A series of experiments were conducted at a bench scale reactor to investigate the effects of key influencing factors on the Hg0 removal from flue gas using the prepared diperiodatoargentate (III) (DPA) as an oxidant, trace ruthenium(III) as a catalyst, respectively. The experimental results showed that the average Hg0 removal efficiency reached to 87.5% under the optimal conditions in which the DPA concentration was 1.03 mmol/L, catalyst concentration was 2.0 μmol/L, reaction temperature was 40 °C and solution pH was 8.5. Meanwhile, it was found from the experiments that the high concentrations of SO2 and NO could inhibit the Hg0 removal due to the competition between Hg0 and SO2/NO, while the lower NO concentration exhibited a slight promotion for Hg0 removal. The evolutions of DPA(III) and Ru(III) before and after the reaction were characterized by an ultraviolet visible spectrophotometer (UV–vis), from which, the promotional mechanism of Ru(III) on Hg0 removal was analyzed. The spent solution was analyzed by a cold vapor atomic fluorescence spectrometer (CVAFS), which verified that Hg0 was oxidized into Hg2+ by the catalytic system of DPA(III)-Ru(III), and DPA was converted into Ag+.

Spectrophotometric Determination of Trace Ruthenium by its Catalytic Effect on Oxidation of Switzerland Pigment with KIO<sub>4</sub>

A spectrophotometric method for the determination of ruthenium (III) is described, based on its catalytic effect on the oxidation reaction of switerland pigment with potassium periodate in 0.016 mol/L of hydrogen chloride medium and in the presence of OP emulsifier (p-iso-octyl phenoxy polyethoxy ethanol) at 100 °C. The above reaction is followed spectrophotometrically by measuring the decrease in the absorbance at 608 nm for the catalytic reaction of switerland pigment. The calibration curve for the recommended method was linear in the concentration range over 0.041.0 μg/L and the detection limit of the method for Ru (III) is 0.012 μg/L. The influence of the factors such as acidity, concentration of reactants, reaction time, temperature and co-existing ions on the reaction is discussed. The optimum conditions of reaction are established and some kinetic parameters are determined. The apparent activation energy of catalytic reaction is 100.48 kJ/mol. The relative standard deviation for the determination of ruthenium (III) at the concentration of 0.02 μg/25 mL is calculated to be 2.3 % (n=11). In combination with distilled separation, the method has been successfully applied for the determination of trace ruthenium (III) in some ores and metallurgy proucts with the relative standard deviations (RSD) over 2.9 %3.8 % and the recovery over 98.2 %-103.6 %.

Kinetic Spectrophotometric Method for the Determination of Trace Ruthenium(III) by its Catalytic Effect on the Oxidation of Dibromo Caboxy Arsenazo with Bromate in Cationic Micellar Media

A spectrophotometric method was developed for the determination of trace Ru (III) is described, based on its catalytic effect of Ru (III) on the oxidation of dibromo caboxy arsenazo (DBCAA) by bromate in acidic and micellar medium at 100 °C. The reaction was monitored spectrophotometrically by measuring the decrease in the absorbance of the catalytic reaction of DBCAA at 530 nm with a fixed-time method. The calibration curve for the recommended method was linear in the concentration range over 0.037–1.0 µg/L and the detection limit of the method for Ru (III) was 0.011 µg/L. The method was applied to the determination of Ru (III) in some ores and metallurgy products. The results are in good agreement with the recommend values with the relative standard deviation of 2.6 %–3.8 % and the recovery of 97.2 %–104.3 %.

A Simple and Sensitive Spectrophotometric Method for the Determination of Trace Ruthenium with its Catalytic Effect on the Oxidation of Rhodamine 6G by KBrO<sub>3</sub> in Micellar Media

A simple catalytic kinetic spectrophotometric method was developed for the determination of trace Ru (III) in the range of 0.033–1.00 μg/L. The method is based on the catalytic effect of Ru (III) on the oxidation of rhodamine 6G (Rh 6G) by bromate in micellar media. The reaction was monitored spectrophotometrically by measuring the decrease in the absorbance of Rh 6G at 520 nm with a fixed-time method. The limit of detection is 0.010 μg/L Ru (III). The relative standard deviation for the determination of 0.010 and 0.020 μg/25mL Ru (III) was 2.9 % and 2.5 %, respectively. The method was applied to the determination of Ru (III) in some ores and metallurgy products.

Spctrophotometric Determination of Trace Ruthenium by its Catalytic Effect on Oxidation of 3,5-DiBr-PADAP with KIO<sub>4</sub>

A spectrophotometric method for the determination of ruthenium (III) is described, based on its catalytic effect on the oxidation reaction of 2-[(3,5-dibromo-2-pyridy)azo]-5-diethylaminophenol (3,5-diBr-PADAP) with potassium periodate in 0.008 mol/L sodium hydroxide medium and in the presence of OP emulsifier (p-iso-octyl phenoxy polyethoxy ethanol) at 100 °C. The above reaction is followed spectrophotometrically by measuring the decrease in the absorbance at 530 nm for the catalytic reaction of 3,5-diBr-PADAP. The calibration curve for the recommended method was linear in the concentration range over 0.04 µg/L–1.0 µg/L and the detection limit of the method for Ru (III) is 0.012 µg/L. The influence of the factors such as acidity, concentration of reactants, reaction time, temperature and co-existing ions on the reaction is discussed. The optimum conditions of reaction are established and some kinetic parameters are determined. The apparent activation energy of catalytic reaction is 100.48 kJ/mol. The relative standard deviation for the determination of ruthenium (III) at the concentration of 0.02 µg/25mL is calculated to be 2.30 % (n=11). In combination with distilled separation, the method has been successfully applied for the determination of trace ruthenium (III) in some ores and metallurgy products with the relative standard deviations (RSD) over 1.8 %–2.9 % and the recovery over 98.1 %–103.1 %.

Co and Fe Catalysed Fischer–Tropsch Synthesis in Biofuel Production

Synthesis of liquid biofuels from synthesis gas is considered. A series of Co, Co/Ru and Fe catalysts supported by three Al2O3 based supports were prepared and tested for the Fischer–Tropsch (FT) reaction. The effects of supports and precursor salts on the activity of the catalysts were studied in the hydrogenation of CO using H2/CO in a ratio of 2:1. The most active catalysts were tested with gas mixture having a composition close to synthesis gas derived by gasification of biomass. The combination of precursor salt and support is significant in order to get an active catalyst. Cobalt-based catalysts with traces of ruthenium on a small particle support proved to be the most active in the production of hydrocarbons with FT reaction.

Extractive Separation and Spectrophotometric Determination of Traces of Ruthenium from Mixtures Containing Excess Platinum Group Metals

A highly selective, sensitive, and rapid method has been developed for the spectrophotometric determination of ruthenium with 5-chloro-2-hydroxythiobenzhydrazide after extraction into molten naphthalene. Ruthenium was determined in the range 1.2–4.5 ppm. The complex was stable for more than 12 h with molar absorptivity of 1.516 × 104 L mol−1 cm−1 and detection limit of 0.0066 ppm. The method was found to be selective for ruthenium in the presence of a large number of diverse ions. Ruthenium was determined in various synthetic mixtures. The method permits the sequential separation and determination of ruthenium, osmium, and platinum from their mixtures.

Catalytic effects of trace ruthenium on oxidation of dimethyl yellow with bromate and its application

Abstract A spectrophotometric method for the determination of ruthenium(III) is described, based on its catalytic effect on the oxidation reaction of dimethyl yellow (DMY) with potassium bromate in an acid solution medium and in the presence of an OP emulsifier ( p - iso -octyl phenoxy polyethoxy ethanol) at 100 °C. This reaction was followed spectrophotometrically by measuring the decrease in the absorbance at 530 nm of the catalytic reaction of DMY. The calibration curve for the recommended method was linear in the concentration range over 0.0–1.0 μg/Land the detection limit of the method for Ru(III) was 0.01 μg/L. The method is highly sensitive, selective and very stable and has been successfully applied for the determination of trace amounts of ruthenium in some ores and metallurgy products with the relative standard deviations (RSD) over 1.6%–2.8% and a recovery over 98.7%–104.0%.

Application of ruthenium catalyzed oxidation of [tris(2-aminoethyl)amine] in trace determination of ruthenium in environmental water samples

The ruthenium catalyzed oxidation of tris(2-aminoethyl)amine (TREN) by hexacyanoferrate(III) has been utilized for the development of a new and sensitive catalytic kinetic method (CKM) for the determination of ruthenium(III). The reaction was followed spectrophotometrically by the decrease in absorbance at 420 nm ( λ max of [Fe(CN) 6] 3−). The CKM developed utilizes fixed time procedure under optimum reaction conditions where the change in absorbance (Δ A t ) versus ruthenium(III) concentrations is plotted. The calibration curve recommended for the method is linear in the concentration range 10.11–252.67 ng ml −1 with very good accuracy and reproducibility and a maximum error 2.20%. The detection limits of the method for ruthenium(III) corresponding to 10, 15 and 20 min are 8.02, 5.03 and 3.15 ng ml −1, respectively. The ruthenium(III) has also been determined in the presence of several other interfering and non-interfering cations and anions and no foreign ions interfered in the determination of ruthenium(III) up to five-fold higher concentration of the foreign ions tested. The method is highly sensitive, selective and stable. It has successfully been applied for the determination of trace ruthenium(III) in some synthetic and environmental water samples. A review of most of the published catalytic kinetic and some other important methods for the determination of ruthenium has also been presented.

Analysis of trace ruthenium in meteoritic FeNi minerals by microbeam XRF using synchrotron radiation.

Distributions of trace ruthenium (Ru) in submilimeter sized areas of metallic FeNi minerals in iron meteorites have been studied by microbeam X-ray fluorescence analysis using synchrotron orbital radiation (SR-XRF) at Photon Factory, National Laboratory for High Energy Physics, Japan. Samples of iron meteorites of groups IA and IIA were irradiated by monochromatized X-ray beam of 22.5 and 23.0 KeV with beam size of 0.5×0.5 to 0.25×0.25 mm squares. A calibration curve was constructed for the standard FeNi alloys doped with 10 to 1000 ppm Ru. The Ru concentrations of ALH77283 (IA) kamacites were analyzed to be about 3 and 5 ppm. Ru in group IIA analyzed in this study (Bennett County, Coahuila, Scottsville, and Walker County) ranges from 13 to 33 ppm. These Ru concentrations of group IIA fall within the range of IIA previously reported. This study has shown that the non-destructive SR-XRF method can easily determine Ru concentration in iron meteorites, and that this method can be used to classify iron meteorites of groups IA and IIA on the basis of Ru versus Ni diagram.

Catalytic Spectrophotometric Determination of Ruthenium by Flow Injection Analysis Using Amido Black 10B and KIO4

AbstractA new method has been developed for the determination of trace ruthenium by flow injection analysis. The proposed method is rapid, simple and sensitive. The method has a limit of detection for ruthenium of 0.050 μg/mL and permits 60 determinations per hour. The method has been applied to determine ruthenium in refined ore with satisfactory results.

Studies on flow injection analysis of platinum metals: I. Flow injection catalytic determination of ruthenium by phthalin-hydrogen peroxide reaction

A new method has been developed for the determination of trace ruthenium by flow injection analysis. The proposed method is rapid, simple and sensitive. The method has a limit of detection for ruthenium of 0.020 μg/mL and permits 70 determinations per hour. The method has been applied to determine ruthenium in refined ore with satisfactory result.

Sorption of trace amounts of ruthenium, manganese and europium on iron(III) hydroxide

The effect of pH on the sorption of trace amounts of ruthenium, manganese and europium on iron(III) hydroxide was studied by radiotracer techniques. The effect of amount of sorbent and duration of the contact between the sorbate and the sorbent were also studied. The results indicate that an iron(III) hydroxide precipitate can be used for the preconcentration of traces of ruthenium, manganese and europium.

Determination of traces of ruthenium by neutron activation analysis using a polyethylene film

A neutron activation analytical method is described for the determination of traces of ruthenium. Acid solution of an inorganic chemical or seaweed ash is heated in a conical flask with oxidants, ruthenium ingredient is distilled and fixed on a polyethylene film, which is placed on the top of the flask. Many films were irradiated together in a thermal neutron flux, and after about a month γ-ray peak counts under the 497 keV peak of103Ru were measured with a well-type NaI(Tl) or a Ge(Li) detector. In the chemicals of fifty one elements, compounds of four platinum metals were contaminated with 2100-150 ppb Ru, and Ga, In, Tm, Tb, Yb: all trivalent elements contained 510-16 ppb Ru. The ruthenium content of all other chemicals were of ppb order or less. In these, Ga, In, Tm and Yb were known as scintigram elements of cancer. In the ash of Porphyra tenera 2 ppb Ru was detected.