Carbon black Catalyst

Yano H, Higuchi E, Uchida H, Watanabe M. 2006a. Temperature dependence of oxygen reduction activity at Nafion-coated bulk Pt and Pt/carbon black catalysts. J Phys Chem B 110 16544-16549. 

Boudart and Ptak (77) confirmed this enhancement of selectivity in isomerization on the (111) faces by comparing the reactions of neopentane on two 1% Pt/carbon black catalysts of exactly the same dispersion, 0.35. One of the catalysts had been fired at high temperature (900°C), and such a treatment, according to the work of Lyon and Somorjai (188), is expected to favor the formation of randomly distributed (111) facets. It is remarkable that the selectivity in isomerization was five times larger on the sintered catalyst than on the nonsintered one. 

Identified a preparation for platinum on carbon black catalyst that provides -60% reduction in precious metal grams/kW compared to current commercial preparations... 

Carbon Black Catalyst Type A Carbon Black Catalyst Type C... 

Carbon Black Catalyst Type B Carbon Black Catalyst Type D... 

Figure 15. Cyclic voltammograms of the Nz plasma treated Pt/carbon blacks catalysts.

Hara, M., Lee, M., Liu, C.H., Chen, B.H., Yamashita, Y., Uchida, M., Uchida, H. Watanahe, M. Electrochemical and Raman spectroscopic evaluation of Pt/graphitized carbon black catalyst durability for the start/stop operating condition of polymer electrolyte fuel-cells. Electrochim. Acta 70 (2012), pp. 171-181. 

Auxiliary rubber agents, azodicarbon-amide, carbon blacks, catalysts, cross-hnking agents, master batches, paint auxiliaries, thixotropic agents... 

In order to decrease the mass transport limitations encountered in PEMFC electrodes, which are prepared with Pt/carbon black catalysts, it was recently proposed to replace the classical carbon black support by carbon xerogels [2], i.e. nanostmctured materials with well defined pore texture prepared by evaporative drying and pyrolysis of organic gels. Carbon xerogels allow for better gas/water diffusion within the pore texture of the electrode and better contact between the platinum particles and the ionomer (Nafion ). 

Many solids have foreign atoms or molecular groupings on their surfaces that are so tightly held that they do not really enter into adsorption-desorption equilibrium and so can be regarded as part of the surface structure. The partial surface oxidation of carbon blacks has been mentioned as having an important influence on their adsorptive behavior (Section X-3A) depending on conditions, the oxidized surface may be acidic or basic (see Ref. 61), and the surface pattern of the carbon rings may be affected [62]. As one other example, the chemical nature of the acidic sites of silica-alumina catalysts has been a subject of much discussion. The main question has been whether the sites represented Brpnsted (proton donor) or Lewis (electron-acceptor) acids. Hall... 

The analysis is thus relatively exact for heterogeneous surfaces and is especially valuable for analyzing changes in an adsorbent following one or another treatment. An example is shown in Fig. XVII-24 [160]. This type of application has also been made to carbon blacks and silica-alumina catalysts [106a]. House and Jaycock [161] compared the Ross-Olivier [55] and Adamson-Ling... 

Mamzen Oil Co. has developed various Ziegler-Natta catalysts that can produce poly(butadiene-i //-prop5iene) (PBR) (78). PBR shows tack (self-adhesion) and green (unvulcanized) dynamic properties superior to those of BR and EPDM. Carbon black-loaded vulcanizates can be compounded to give high strength and elongation at break (79,80). PBR can also be covulcanized with SBR, BR, and EPDM. 

Typical applications in the chemical field (Beaver, op. cit.) include detarring of manufactured gas, removal of acid mist and impurities in contact sulfuric acid plants, recovery of phosphoric acid mists, removal of dusts in gases from roasters, sintering machines, calciners, cement and lime Idlns, blast furnaces, carbon-black furnaces, regenerators on fluid-catalyst units, chemical-recoveiy furnaces in soda and sulfate pulp mills, and gypsum kettles. Figure 17-74 shows a vertical-flow steel-plate-type precipitator similar to a type used for catalyst-dust collection in certain fluid-catalyst plants. 

Physical adsorption—surface areas of any stable solids, e.g., oxides used as catalyst supports and carbon black Chemisorption—measurements of particle sizes of metal powders, and of supported metals in catalysts... 

In this article, we will discuss the use of physical adsorption to determine the total surface areas of finely divided powders or solids, e.g., clay, carbon black, silica, inorganic pigments, polymers, alumina, and so forth. The use of chemisorption is confined to the measurements of metal surface areas of finely divided metals, such as powders, evaporated metal films, and those found in supported metal catalysts. 

Step 8 Preparation of (2.3-isopropyiidenedioxy)-propyi anthraniiate-80 g oi (2,3-Isopropyl-idenedioxy)-propyl o-nitrobenzoate, obtained as described in Step A, were subjected to hydrogenation for a period of one hour in 800 cc of absolute alcohol in the presence of 2 g of palladized carbon black as catalyst. The reaction mixture was filtered and the filtrate was evaporated under vacuum to obtain 70.5 g (being a yield of 98.5%) of (2,3-isopropylidenedl-oxy)-propyl anthranilate in the form of a yellow oil which distilled at 159°C to 160°C under 0.5 mm of pressure. 

The effect of synthesis gas composition on conversion, catalyst life, carbon black formation, etc. was determined in numerous tests. Characteristic variables in the synthesis gas composition are the H2/CO ratio, residual C02 content, and content of trace components in the form of higher hydrocarbons and catalyst poisons. 

In all tests, there was no sign of carbon black formation. Pressure drop over the reactor remained constant during the whole operating period, and there was no accumulation of free carbon on the catalyst. Analysis of the discharged catalyst for free carbon revealed that the carbon content was lower than the amount of carbon added to the catalyst as a pelletizing aid. 

Dr. Moeller I must say you can handle the carbon black formation with the structure of your catalyst. You can produce a catalyst with which you can go farther into the region of carbon black formation than when using a different catalyst. I think these results are published, especially those from IC1. We had the same experience when we developed our catalyst together with Badische. You can go farther into the carbon black region. But, on the other hand, you can adjust your system so that there is no need to go into the carbon black region. 

For the support material of electro-catalysts in PEMFC, Vulcan XC72(Cabot) has been widely used. This carbon black has been successfully employed for the fuel cell applications for its good electric conductivity and high chemical/physical stability. But higher amount of active metals in the electro-catalysts, compared to the general purpose catalysts, make it difficult to control the metal size and the degree of distribution. This is mainly because of the restricted surface area of Vulcan XC72 carbon black. Thus complex and careM processes are necessary to get well dispersed fine active metal particles[4,5]. 

As surface area and pore structure are properties of key importance for any catalyst or support material, we will first describe how these properties can be measured. First, it is useful to draw a clear borderline between roughness and porosity. If most features on a surface are deeper than they are wide, then we call the surface porous (Fig. 5.16). Although it is convenient to think about pores in terms of hollow cylinders, one should realize that pores may have all kinds of shapes. The pore system of zeolites consists of microporous channels and cages, whereas the pores of a silica gel support are formed by the interstices between spheres. Alumina and carbon black, on the other hand, have platelet structures, resulting in slit-shaped pores. All support materials may contain micro, meso and macropores (see text box for definitions). 

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