Questions tagged [adsorption]
The adhesion of atoms, ions, or molecules from a gas, liquid, or dissolved solid to a surface.
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Why is chemisorption "irreversible"?
I keep reading that chemisorption is irreversible. But why? (It's obviously not used in the context of thermodynamics.) Wouldn't heating and other such actions lead to the reversal of chemisorption ...
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What is the relation between DFT-calculated adsorption energy for a dye–fiber dimer and the concepts of stability, exothermicity, or endothermicity
I’m working on a DFT-based study of dye–fiber interactions. I calculated the interaction energy between a dye molecule and a fiber monomer by computing the total energy of the dye–fiber dimer and ...
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How to explain discrepancy between AEROWIN-predicted and observed gas-particle partitioning for SVOCs? Are there better tools?
I study the behavior of organic matter in the atmosphere, especially gas-particle partitioning. When using the AEROWIN module in EPI Suite v4.11 to estimate partitioning of low-molecular-weight semi-...
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Adsorbent or scavenger for working at low H2 concentration in a bioreactor
I am designing an experiment where, by the means of a microbial-catalysed reaction in an aqueous solution, $H_2$ is produced. It is our interest to decrease the hydrogen concentration as much as ...
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Why is H2 split heterolytically in the chemisorption on ZnO surface while it is split homolytically on Pt surface?
Read about homolytic and heterolytic dissociation of H2 on Pt and ZnO surface. What are the mechanisms that cause the different cleavage, what bonds are formed between the hydrogen atoms and the ...
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How to prepare sodium orthovanadate (Na3VO4) solutions buffered at pH = 7.5?
I need to conduct adsorption studies on vanadium using various substances like biochars and nanooxides. To prepare vanadium solutions up to 320 ppm with a pH buffered at 7.5 using PIPES buffer, how ...
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DIY method for regenerating activated carbon in air filters
I am interested in regenerating activated carbon used in general house-hold air filters. I am looking for a sufficiently efficient and easy method to do this in home setting. A little tinkering in a ...
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Activated charcoal for water filtration: Granules vs Pellets
NOTE:
After further investigation into the producer I found out that granules are made of 100% coconut shell whereas pellets of 100% hard coal.
This renders this question meaningless.
Apologies for ...
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Is the line between physisorption and chemisorption species specific?
I was studying about heterogenous catalysis, and my Professor said something along the line, "When the adsorption energy is comparable to (or lower than) heat of evaporation, then it is ...
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Is BET equation applicable to only monolayer adsorption range?
One of my senior colleagues is stating that although BET adsorption isotherm equation hypothesises about multilayer adsorption, the P/P0 values (usually from 0.05 to 0.3) accountable for BET surface ...
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Enthalpy of adsorption and adsorption rate
What I want to know is about the adsorption enthalpy change by the change of surface coverage and the adsorption rate. In general situations, adsorption would be exothermic. So in the Gibbs free ...
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How do metal hydrides behave in a non-hydrogen closed system?
I am curious about the fundamentals of metal hydrides and how adsorption/desorption works in non-hydrogen systems. My understanding is that the atom ratio M/Hx of the metal hydride is a function of ...
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What is the chemical mechanism at work during the carboxylation of graphene oxides?
The literature describes carboxylation as an efficient technique to increase the ability of graphene oxide to adsorb metals, as it increases the content of carboxylic acids in the material, while ...
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Do "pseudo Van der Waals" gases exist?
In college, when deriving the Langmuir isotherm for gas-solid adsorption, the professor proposed a modified version of the Van der Waals state equation, what he called the "pseudo Van der Waals ...
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How to minimize sample dispersion during spotting for paper electrophoresis?
I am separating highly polar amino acids and their derivatives using paper electrophoresis. This requires pre-wetting a piece of filter paper with electrophoresis buffer (in this case, carbonate-...
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