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Feedstock Preparation by Gasification
Published in James G. Speight, Handbook of Petrochemical Processes, 2019
Ruthenium-containing catalysts are used primarily in the production of ammonia. It has been shown that ruthenium catalysts provide 5–10 times higher reactivity rates than other catalysts. However, ruthenium quickly becomes inactive due to its necessary supporting material, such as activated carbon, which is used to achieve effective reactivity. However, during the process, the carbon is consumed, thereby reducing the effect of the ruthenium catalyst.
Ruthenium Compounds: A New Approach in Nanochemistry
Published in Ajay Kumar Mishra, Lallan Mishra, Ruthenium Chemistry, 2018
Pradeep Pratap Singha, Ambikab
Ruthenium (Ru) is a transition metal in VIII group and is inert to most chemicals. The chemistry of Ru is currently receiving a lot of attention, primarily because its complexes have good electron transfer and energy transfer properties (Collin et al., 1994). Ru is a versatile catalyst, and have been investigated for applications such as electrocatalysts, materials for electrochemical supercapacitors, catalysts for H2 production, or CO oxidizing catalysts, in ammonia synthesis and cellulose hydrolysis (Abu-Dief and Mohamed, 2015). Ru can exist in a range of oxidation states (II, III, and IV) under physiologically relevant conditions due to which it can be utilized in pharmacological applications, for example Ru coordination compounds have shown promising application as anticancer agents, in the treatment of eye melanomas. New Ru-based compounds with fewer and less severe side effects, could replace longstanding platinum (Pt)-based anticancer drugs (Allardyce and Dyson, 2001). Ru compounds are being researched for use in a number of developing solar energy technologies (Nosheen et al., 2016). They have also been utilized as a probe for upconversion luminescence sensing and bioimaging of intracellular metal ions. This article will focus on the emerging concept of Ru nanoparticles and their diverse applications in different areas.
Ru, 44]
Published in Alina Kabata-Pendias, Barbara Szteke, Trace Elements in Abiotic and Biotic Environments, 2015
Alina Kabata-Pendias, Barbara Szteke
Ruthenium (Ru) is a hard, white metal of group 8 in the periodic table of elements and is a member of the platinum group metals (PGMs). It is resistant to acids, but reacts with alkalis, especially under oxidizing conditions. Its mean concentration in the Earth’s crust is about 1 µg/kg, whereas its contents in rocks vary from 0.01 to 60 µg/kg. It usually occurs as a minor component of Pt ores. The PGMs mined in South Africa contain, on average, 11% Ru, whereas the PGMs mined in the former USSR contain only 2% Ru. It may also be associated with ores of some base metals, such as Fe, Ni, and Cu. Fission products of 235U contain significant amounts of Ru, and therefore, used nuclear fuel might be its possible source.
Study on a Ru(III) complex containing picolinate with potent inhibition effect against melanoma cell line
Published in Journal of Coordination Chemistry, 2022
Sara Abdolmaleki, Azade Aslani, Alireza Aliabadi, Saeed Khazayel, S. Mojtaba Amininasab, Zhila Izadi, Mohammad Ghadermazi, Elham Motieiyan, Domenica Marabello, Vitor Hugo Nunes Rodrigues
In several reviews, mechanism and action modes for ruthenium-based anticancer metallotherapeutics were analyzed and confirmed that these compounds have many merits over platinum-based therapeutics. The activity toward some cancer cells resistant to cisplatin, low side-effects, high selectivity against cancer cell lines compared to normal cells, different ligand-exchange kinetic, transport, and activation mechanisms, can be mentioned as some of these merits [11]. In a study, it was proposed that ruthenium compounds have inherently low toxicity but their ability to mimic iron is often confused with toxicity [12]. Similar chemical properties of ruthenium with iron allow it to mimic iron when bound to biomolecules [13]. It should be mentioned that Ru(III) complexes can interact with plasma proteins such as serum albumin and transferrin and also may bind with nucleic acids [14]. In this circumstance, cancer cells show higher sensitivity to ruthenium complexes concerning an increased requirement for iron and, therefore, the number of transferrin receptors was increased on their surface [15].
Dehydrogenation of ammonia borane by dealloyed ruthenium catalysts
Published in Inorganic and Nano-Metal Chemistry, 2021
Ruthenium (Ru) is one of the most utilized precious catalysts in the hydrogen generation from chemical hydrides. In literature, various studies have been conducted in order to increase the catalytic activity of Ru such as impregnation on substrates,[26–30] embedding in a metal-organic framework,[31] obtaining on support,[32–38] bimetallic structures,[39,40] composites,[41] perovskite structures,[42] stabilizer utilization,[43,44] coordination[45] and encapsulation.[46,47] On the other hand, in this study, sputter alloying and chemical dealloying were applied in order to acquire highly catalytically active Ru catalysts for the dehydrogenation reaction of NH3BH3. Sputter alloying and dealloying was utilized in literature for various applications.[48–51] In this study, Ru and aluminum (Al) were simultaneously sputtered and Al was etched from the obtained Ru-Al alloy by chemical dealloying with sodium hydroxide (NaOH). The remaining Ru particles were analyzed in the hydrogen generation from NH3BH3. The sputtering power, catalyst amount and durability of catalysts were also investigated in the study.
Progress towards the ideal core@shell nanoparticle for fuel cell electrocatalysis
Published in Journal of Experimental Nanoscience, 2018
James S. Walker, Neil V. Rees, Paula M. Mendes
As shown, ruthenium, with an average price of 76.40 $/oz in 2015–2018, is an exception to the rule in that it comes in at least 12 times cheaper than platinum, which has averaged 976.19 $/oz over the same period. Accordingly, researchers have looked to ruthenium as a very eligible candidate for M@Pt studies. In 2013, ordered Ru@Pt nanoparticles were synthesised using a new method which reportedly minimised the formation of crystal lattice deformations. These nanoparticles were subsequently tested in a fuel cell stack to measure their capacity for catalysing the HER at a PEFC anode. Significantly, the researchers tested their nanoparticles with a carbon monoxide-poisoned hydrogen stream and were able to demonstrate enhanced tolerance to poisoning when compared to commercial Pt/C. This effect was ascribed in part at least due to the chemical ordering engendered in the Ru–core following an annealing step at 450 °C [44]. This group once more highlighted the contribution that defined chemical ordering made to the activity and durability of their catalysts. This phenomenon has been further studied, with Cu@Pt–Ru nanoparticles tested as methanol and carbon monoxide oxidation catalysts in two successive works [45,46]. The authors noted in both cases that their nanoparticles demonstrated enhanced tolerance to carbon monoxide poisoning. The enhanced durability of each of the catalysts described highlights a unique property of alloyed Pt/Ru surfaces.