Catalysts binders

The term matrix has different meanings to different people. For some, matrix refers to components of the catalyst other than the zeolite. For others, matrix is a component of the catalyst aside from the zeolite having catalytic activity. Yet for others, matrix refers to the catalyst binder. In this chapter, matrix means components of the catalyst other than zeolite and the term active matrix means the component of the catalyst other than zeolite heaving catalytic activity. 

PSD is an important indicator of the fluidization characteristics of the catalyst, cyclone performance, and the attrition resistance of the catalyst. A drop in fines content indicates the loss of cyclone efficiency. This can be confirmed by the particle size of fines collected downstream of the cyclones. An increase in fines content of the E-cat indicates increased catalyst attrition. This can be due to changes in fresh catalyst binder quality, steam leaks, and/or internal mechanical problems, such as those involving the air distributor or slide vah es. 

Changes in the fresh catalyst s physical properties may contribute to catalyst losses. The losses could be due to the fresh catalyst s being soft. Softness is evidenced by the quality of the catalyst binder and the large amount of 0-40 microns. It will increase the attrition tendency of the catalyst and thus its losses. 

The zeolite crystallites were applied as a ca, 10 /im layer on the surface of fused silica particles of ca. 0.3 mm diameter, which corresponds to a zeolite-quartz-mass-ratio of 1 14 (Fig. 1). No catalyst binder was used. This ideal... 

Bravo et al. [29] dealt with the coating of a commercial CuO/ZnO catalyst on quartz and fused-silica capillaries for future application in micro channels. The catalyst was mixed with boehmite as binder and water at a mass ratio of44 11 100. The boehmite was treated with hydrochloric or nitric acid before. The capillaries were pretreated with a hot sulfuric acid/solid oxidation step before coating. The capillaries were filled with the catalyst/binder suspension and then cleared with air. In this way, catalyst coatings up to 25 pm thick were obtained. The coatings were applied to methanol steam reforming (see Section 2.4.1). 

Catapal . [Visu] Alumina monohydrate catalyst binders and supports. 

The graphitization of the diamond surface, described in Section 1.3.3.2, is important in terms of infiltration of the solvent/catalyst binder. Metals such as cobalt dissolve graphite more readily than diamond at the sintering pressures (Fig. 9b). Hence, the more graphitization that has taken place, the more cobalt is expected to be in the final material. 

Uses Binder for inorg. film, inorg. fibrous shapes of ceramic and glass fiber, and for treatment of steel antistat catalyst binder textile treatment painting vehicle paper treatment Prqrethes Transparent 11-14 nm particle size vise. 1-3 cps pH 2-4 20% SiO, 80% water... 

Uses Antistat catalyst binder binder for inorg. film textile treatment ... 

Uses Binder for precision casting metal surf, treatment paint vehicle catalyst binder paper treatment binder for inorganic film Features Features exc. heat resist., antistatic props., transparency, gelation, large surf, area... 

Modified zeolites for use in an industrial reactor should have the right physical form and shape implied by the choice of the reactor (Chapter 9). FCC in a fluid-bed reactor requires spherical particles (70-100 [im), obtained by spray drying of the [im-sized USY zeolite crystals in the presence of a binder, viz. silica, alumina, and clays [21]. Extrusion requires a binding agent that attributes to the zeolite/binder mixture tixotropic properties in the extruder [22]. As the catalyst binder may be active, it exceeds the role of diluent agent for the active zeolite [21]. Indeed, the steam stability of some zeolites is known to be enhanced in a binder[Pg.244]

As electrochemical reaction sites, CLs play an extremely important rote in the performance of fuel cell stacks. A CL mainly consists of catalyst, support and binder. The CL is usually coated on the surface of the GDL. Another method has the CL directly applied to the membrane (catalyst coated membrane, CCM). The selection of the components, the proper ratios of those components, the structure of the formed CL and the formation method of the CL are critical factors in the performance of a fuel cell. The stability of the fuel cell performance is directly related to the stabilities of the catalyst, binder and support in flie CL. Degradation of catalytic activity would be due to the agglomeration of the eatalyst particles and their detachment from the support, the degradation of the binder, and the oxidation and corrosion of the support, particularly at the cathode. Further improvement in CL performance is possible. The basic technical considerations include how to maximize the three-phase interface of the CL, how to stabilize the metal particles on the support, and how to reduce the degradation of the components in the CL. 

Saito, T., Roberts, T.H., Long, T.E., Logan, B.E. Hickner, M.A. Neutral hydrophilic cathode catalyst binders for microbial fuel-cells. Energy Environ. Sci. 4 (2011), pp. 928-934. 

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