Platinum supported

The OLEFLEX process uses multiple side-by-side, radial flow, moving-bed reactors connected in series. The heat of reaction is suppHed by preheated feed and interstage heaters. The gas-phase reaction is carried out over a catalyst, platinum supported over alumina, under very near isothermal conditions. The first commercial installation of this technology, having an annual capacity of 100,000 t, was made in 1990 by the National Petrochemical Corporation in Thailand. A second unit, at 245,000 t capacity, has been built in South Korea by the ISU Chemical Company (70). 

Some catalysts used in gasoline manufacture consist of finely divided platinum supported on an inert solid. Suppose that the platinum is formed by the high temperature reaction between platinum dioxide, PtOj, and hydrogen gas to form platinum metal and water. 

Liquid film state under reactive distillation conditions for the dehydrogenation of decalin on platinum supported on active carbon and boehmite... 

Supported platinum. The STEM and TPD data for platinum supported on alumina and silica are summarized In Table I. The platlnum-slllca samples show a high degree of variability In size and mass. This variability Is Indicative of the mobility of platinum on silica at elevated temperatures, l.e., 500°C. These samples were of little... 

New aluminophosphate oxynitrides solid basic catalysts have been synthesised by activation under ammonia of an AIPO4 precursor. When the nitrogen content increases, XPS points out two types of nitrogen phosphorus bonding. The conversions in Knoevenagel condensation are related to the surface nitrogen content. Platinum supported on aluminophosphate oxynitride is an active catalyst for isobutane dehydrogenation. 

Figure 7 compares in function of time the activities of catalyst B and platinum supported on magnesium oxide MgO, a well-known basic industrial catalyst. 

P 15] Cyclohexene was purified prior to use in a micro reactor experiment [11]. As catalyst, standard platinum supported on alumina powder with platinum contents... 

Blurton KF, Kunz HR, Rutt DR. 1978. Surface area loss of platinum supported on graphite. Electrochim Acta 23 183-190. 

Gruver GA, Pascoe RE, Kunz HR. 1980. Surface Area loss of platinum supported on carhon in phosphoric acid electrolyte. J Electrochem Soc 127 1219-1224. 

Previously, we have developed several techniques for platinum supported zeolite catalysts to improve the benzene product purity, including on-line sulfiding [3], precoking [6], and dual-bed catalyst system [7]. We report herein an in-depth investigation on the synergism of proton zeolite and platinum supported ZSM-12 catalyst (Pt/Z12) in a cascade dual-catalyst system. 

Tenteleff Also spelled Tentelew. An early version of the Contact process for making sulfuric acid. The catalyst was platinum supported on asbestos. Invented in 1907 and operated by the Gesellschaft der Tentelewschen Chemischen Fabrik, St. Petersberg. 

An interesting catalyst is the platinum supported on graphite. Fig. 12 shows a bright field image. The... 

A PEFC consists of two electrodes in contact with an electrolyte membrane (Fig. 14.7). The membrane is designed as an electronic insulator material separating the reactants (H2 and 02/air) and allowing only the transport of protons towards the electrodes. The electrodes are constituted of a porous gas diffusion layer (GDL) and a catalyst (usually platinum supported on high surface area carbon) containing active layer. This assembly is sandwiched between two electrically conducting bipolar plates within which gas distribution channels are integrated [96]. 

Figure 2.15 shows a schematic representation of the CCM manufacturing process. The first step for CCM preparation comprises mixing the reactive layer materials (e.g., platinum-supported carbonblack) with different amounts of PTFE, polymer electrolyte powder (e.g., Nafion), and/or filler materials... 

With gem-dimethyl hydrocarbons, isomerization and demethylation compete with each other. Isomerization predominates in the presence of acidic centers. Over platinum supported by acidic alumina 1,1-dimethylcyclo-hexane gave 18% toluene and 60% o-xylene (percentages of the total aro-... 

The experiments of nanocatalytic liquefaction of hydrogen were carried out using a platinum-supported carbon nanolayer. In the experiments, H PtClj, 6HjO or H PtClj was used as a Pt precursor. To prepare the Pt catalytic reaction nanolayer, the required amounts of H PtClj were mixed with 5 wt.% carbon prepared by burning naphthalene in air (Demirbas, 2008). 

The zeolite provides the environment for shape selective chemistry and is also a high surface area support on which to disperse platinum in a relatively confined environment. The small platinum crystals within the zeolite channels and the orientation effect of the channel window are responsible for the high efficiency of the Pt-KL catalyst to convert linear paraffin to aromatics. Zeolite KL also provides an electron rich environment to enhance stronger platinum-substrate interaction via stronger platinum-support interaction. A review on the subject can be found in the article written by Meriasdeau and Naccache [85]. 

Platinum supported on carbon (Pt/C) was tested as solid catalysts in the oxidation of sucrose using molecular oxygen as oxidant (Scheme 10). The reaction was carried out in water and under atmospheric pressure. The support strongly influences the reaction and Pt/C was found more efficient than Pt/Alumina at 353 K. Over Pt/C, at a pH of 9, mono-, di-, and tricarboxylate derivatives were mainly obtained with a tricarboxylate yield of 35% [103]. 

As described in Section 3 of Chapter 2, multi-electron processes are important for designing conversion systems. Noble metals are most potent catalysts to realize a multi-electron catalytic reaction. It is well known that the activity of a metal catalyst increases remarkably in a colloidal dispersion. Synthetic polymers have often been used to stabilize the colloids. Colloidal platinum supported on synthetic polymers is attracting notice in the field of photochemical solar energy conversion, because it reduces protons by MV to evolve H2 gas.la)... 

B. Sintering Inhibition Mechanism of Platinum Supported on Ceria-based Oxide... 

Mukesh, D., Kenney, C. N., and Morton, W. (1983). Concentration oscillations of carbon monoxide, oxygen and 1-butene over a platinum supported catalyst. Chem. Eng. Sci., 38, 69-77. 

Dual-function catalysts possessing both metallic and acidic sites bring about more complex transformations. Carbocationic cyclization and isomerization as well as reactions characteristic of metals occurring in parallel or in subsequent steps offer new reaction pathways. Alternative reactions may result in the formation of the same products in various multistep pathways. Mechanical mixtures of acidic supports (silica-alumina) and platinum gave results similar to those of platinum supported on acidic alumina.214,215 This indicates that proximity of the active sites is not a requirement for bifunctional catalysis, that is, that the two different functions seem to operate independently. 

At about 250° C a catalyst consisting of a low sodium zeolite and a noble metal is used in a recently developed process (3). It is claimed that no extensive feed pretreatment is required and that the stability of the catalyst is not impaired by common feed impurities. An older process using a catalyst consisting of platinum supported on amorphous silica-alumina (4) operates at 400° C. Naturally the higher the operation... 

Catalytic synthesis of hydroxylamine from nitrogen oxide and hydrogen is widely used in industry as a constituent part of caprolactam production. The reaction is conducted in aqueous sulfuric acid solution saturated with NO and H2 at 40°C and a pressure of approximately 1 atm. Platinum supported on porous graphite, in the form of fine particles suspended in the intensely stirred solution, is used as a catalyst. The main direction of the reaction is... 

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