Hydrogen Gas Mixtures

With hydrogen this has been deduced from the rapid equilibration of deuterium and hydrogen gas mixture. With water the extent of dissociative chemisorption is not so clearly established. The formation of... 

Monsanto and Ube (Japan) developed membrane processes for purification of hydrogen gas mixtures. This process is based on the selective diffusion of hydrogen through semi-permeable membranes in the form of hollow fibers. The Monsanto PRISM separator process (owned by Air Products as of 2004) uses a polysulfone fiber whereas Ube uses an aromatic polyimide fiber.46... 

In the early experiments of thermal CVD using methane -i- hydrogen gas mixtures, a temperature of about 1000°C and a pressure less than 0.1 atm meant that the formation of graphite was predominant.An activation energy is required to produce carbon and/or hydrogen radicals so that the gas phase and surface reactions leading to predominantly diamond deposition can proceed at a significant rate." ... 

TABLE I 1.4 Equilibrium Ammonia Vapor Concentrations in a 1 3 Nitrogen Hydrogen Gas Mixture Above Liquid Ammonia at I S°C°... 

The TPR was performed in a conventional TPR apparatus, on samples of 20 mg, in a 98% (molar) nitrogen-2%(molar) hydrogen gas mixture, with a gas flow rate of 120 cmVmin and equipped with a thermal conductivity detector. 

Gopalakrishnan, S., Costa, J. C. D. (2008). Hydrogen gas mixture separation by CVD silica membrane. Journal of Membrane Science, 323, 144—147. 

The current efficiency in the chlorate process is conunonly 93-95 % [4]. The deviation from 100 % is caused by side reactions ot the electrodes and in the bulk as well as by CI2 escaping with the cell gas. Oxygen is the major by-product, and oxygen in the cell gas affects not only the electricity consumptirm but is also considered a safety risk as explosive oxygen-hydrogen gas mixtures may form. 

A schematic of the reactor system under consideration is shown in Figure 10.1. The reactor is packed with catalyst particles, and reactants enter the reactor and produce hydrogen in the presence of the catalyst particles. There is a jacket around the reactor so that additional heat can be provided to the reactor. The resulting hydrogen gas mixture is sent to a fuel cell stack where an electrochemical reaction occurs to generate power. The fuel cell stack is composed of several identical hydrogen fuel cells in series. 

A simple chemical reaction of a nitrogen and hydrogen gas mixture in the presence of previously ball-milled boron-nickel powder at 1025°C was utilized by Lim et al. This method successfully generated BNNTs of diameter and lengths ranging from 20 to 40 nm and less the 250 nm, respectively. The process does not involve any harmful precursors and requires a comparatively lower temperature than most of the other reported methods. 

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