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Chemisorption is a kind of adsorption which involves a chemical reaction between the surface and the adsorbate. New chemical bonds are generated at the adsorbent surface. Examples include macroscopic phenomena that can be very obvious, like corrosion [clarification needed], and subtler effects associated with heterogeneous catalysis, where the catalyst and reactants are in different pha
Hydrogen spillover can be characterized by three major steps, the first being where molecular hydrogen is split via dissociative chemisorption into its constitutive atoms on a transition metal catalyst surface, followed by migration from the catalyst to the substrate, culminating in their diffusion throughout the substrate surfaces and/or in ...
The oxidation of hydrocarbons to water and carbon dioxide: 2 C 6 H 6 + 15 O 2 → 12 CO 2 + 6 H 2 O; This process can occur with any of hydrocarbon, but most commonly is performed with petrol or diesel. Asymmetric heterogeneous catalysis facilitates the production of pure enantiomer compounds using chiral heterogeneous catalysts. [26]
Adsorption is present in many natural, physical, biological and chemical systems and is widely used in industrial applications such as heterogeneous catalysts, [9] [10] activated charcoal, capturing and using waste heat to provide cold water for air conditioning and other process requirements (adsorption chillers), synthetic resins, increasing ...
BET theory applies to systems of multilayer adsorption that usually utilizes a probing gas (called the adsorbate) that does not react chemically with the adsorptive (the material upon which the gas attaches to) to quantify specific surface area. Nitrogen is the most commonly employed gaseous adsorbate for probing surface(s).
Now, invoking the condition that the system is in equilibrium, that is, the chemical potential of the adsorbed molecules is equal to that of the molecules in gas phase, we have An example plot of the surface coverage θ A = P/(P + P 0) with respect to the partial pressure of the adsorbate. P 0 = 100 mTorr.
During atomic layer deposition, a film is grown on a substrate by exposing its surface to alternate gaseous species (typically referred to as precursors or reactants). In contrast to chemical vapor deposition, the precursors are never present simultaneously in the reactor, but they are inserted as a series of sequential, non-overlapping pulses.
where R is the gas constant (8.314 J mol −1 K −1), T the temperature (K), Φ v,fresh, the flow rate of the fresh water outflow (m 3 /s), C feed the concentration of ions in the feed water (mol/m 3) and C fresh the ion concentration in the fresh water outflow (mol/m 3) of the CDI cell.