Catalyst spray coating

The expander turbine is designed to minimize the erosive effect of the catalyst particles stiU remaining in the flue gas. The design ensures a uniform distribution of the catalyst particles around the 360° aimulus of the flow path, optimizes the gas flow through both the stationary and rotary blades, and uses modem plasma and flame-spray coatings of the rotor and starter blades for further erosion protection (67). 

Similar to screen printing, the spray coating method [95] is widely used for catalyst fabrication, especially in labs. The major difference between the two is that the viscosity of the ink for spray coating is much lower than that for screen printing. The application apparatus can be a manual spray gun or an auto-spraying system with programmed X-Y axes, movable robotic arm, an ink reservoir and supply loop, ink atomization, and a spray nozzle with adjustable flux and pressure. The catalyst ink can be coated on the gas diffusion layer or cast directly on the membrane. To prevent distortion and swelling of the membrane, either it is converted into Na+ form or a vacuum table is used to fix the membrane. The catalyst layer is dried in situ or put into an oven to remove the solvent. 

Preparation of coatings as free films. The oligomeric esterdlols were mixed with the crosslinkers HMMM or polyfunctional isocyanate. The molar ratio esterdlol/HMMM was 2 1 leading to an OH/OCH3 ratio of 4 6. The OH/NCO ratio was 1 1. Some 1 wt% diethanolamine salt of p-toluene sulphonlc acid, respectively 0.2 wt% Dabco were used as catalyst. The coatings were applied to Bonder 101 plates which had been sprayed with a thin layer (1-2 pm) of teflon. 

Obviously the tertiary structure of the catalyst obtained by cold rolling is optimal and is least efficient for the plasma-sprayed coating. It should be stressed that by variation of the process parameters, also galvanically generated NiZn codeposits yield optimal performance, which is comparable to that of cold-rolled coatings (83). 

Platinum catalyst was introduced into an alumina-based suspension and then spray-coated. The evaporation was performed using porous cylinders of 7 mm diameter and 1 mm height introduced into each individual plate before performing... 

Spray coating of commercial catalysts was successfully applied by Schuessler et al. 

Fignre 5.2f and g shows the metalhzation process on the 3-D microstmctnres. By spray coating, the photoresist fihn is formed on the 3-D topographic stmctnres and patterned by photolithography, (f) Ti/An for cnrrent coUectors is formed by electron-beam deposition and snbseqnent lift-off process, (g) Catalyst layers of the anode and cathode are formed by electroplating Pt-Rn for the anode and Pt for the... 

The maleic anhydride catalyst is vanadium pentoxide spray coated with porous silica to impart attrition resistance. The catalyst needs to be specially treated for attrition resistance for use in the transport bed reactor. Reactor operating conditions are approximately 500°C (930 F) and 1 atm pressure. 

Chem. Descrip. Sodium cumene sulfonate CAS 32073-22-6 EINECS/ELINCS 250-913-5 Uses Hydrotrope, solubilizer for spray-dried prods. catalyst for coatings applies. 

Chem. Descrip. Dibutyl phthalate CAS 84-74-2 EINECS/ELINCS 201-557-4 Uses Solvent/plasticizer in fingernail polish, nail polish remover, hair sprays, org. peroxide catalysts, adhesives, coatings food pkg. adhesives, coatings, paper, cellophane, polymers Features Compat. with cellulosics. methacrylate, PS, PVB, vinyl chloride, urea-formaldehyde, melamine-fomialdehyde, phenolics Regulatory FDA21CFR 175.105,175.300,175.320,176.170,177.1200, 177.2430... 

Thicker membranes from polymers are usually cast as solution (drop, spin, and spray coating), and the membrane forms after evaporation of the solvent. Alternate routes are application of monomers, direct polymerization on the electrode surface, and mechanical attachment of the ready-to-use membranes. Usually, modifiers (mediators, catalysts, enzymes, etc.) are dissolved in the membraneforming solution. Membranes can be generated also by electropolymerization, most commonly from aniline, pyrrole, or thiophene [117-119] the resulting 2D structure can entrap active molecules (e.g., enzymes) or serve as anchors for the actual modifier. Attachment of active molecules to polymeric structures can... 

The respective cathode and anode electrodes were hot pressed onto opposite sides of the proton exchange membrane with the catalyst layer in direct contact with the proton exchange membrane. In some cases an additional thin layer of Nafion solution was spray coated onto the catalyst layer to ensure complete integration of the catalyst layer and membrane. Recommended hot pressing conditions specified by commercial vendors were used, and specific conditions per sample are listed in Table 8.2. 

Uses Hydrotrope, solubilizer for leather and spray-dried prods. catalyst for coatings applies. 

The bed of parallel plates coated with Raney nickel catalyst was much more reactive than the bed of precipitated nickel. This was revealed by the generally lower CO concentration in the product gas during operation with the parallel plate bed for example, after 450 hrs stream time, it was 0.01% with the bed of sprayed Raney nickel (experiment HGR-14) and 0.05% with the bed of precipitated nickel catalyst (experiment HGR-13). 

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