Can molecular sieves absorb methane? 5

Methane cannot be absorbed by molecular sieves, and methane can be absorbed in the following way.

Since methane is a non-polar molecule, it can be absorbed with organic solvents such as CCL4.

Molecular sieve refers to a class of substances with uniform micropores and a pore size comparable to the size of a general molecule. Molecular sieves are widely used as high-efficiency desiccant, selective adsorbents, catalysts, ion exchangers, etc., but the cost of synthesizing molecular sieves from chemical raw materials is very high. Commonly used molecular sieves are crystalline silicates or aluminosilicates, which are pore and cavity systems of molecular size (usually nm) formed by the connection of silicon-oxygen tetrahedra or aluminum-oxygen tetrahedra through oxygen bridge bonds, and have the ability to sieve fluid molecules of different sizes due to the different sizes and shapes of adsorbed molecules.

Adsorption function: The adsorption of substances by molecular sieves is more than physical adsorption (van der Waals force), and its crystal cavities have strong polarity and Coulomb field, and show strong adsorption capacity for polar molecules (such as water) and unsaturated molecules.

Molecular sieves are crystalline silicates or aluminosilicates formed by silicon-oxygen tetrahedra or aluminum-oxygen tetrahedra connected by oxygen bridge bonds. It cannot be absorbed by molecular sieves, and since methane is a non-polar molecule, it can be absorbed with organic solvents such as CCL4.

The molecular critical diameter of CH4 is angstroms, so various types of molecular sieves such as 5A and 10X X, which have a pore size larger than 5 angstroms, can absorb methane.

No! Molecular sieves in the usual sense are used to absorb water.

3A, 4A, 5A Zeolite 4A zeolite can be converted into 3A and 5A zeolites through ion exchange, and has strong selective adsorption capacity due to their different pore sizes. The sodium ions in 4A zeolite are converted into 3A zeolite after being exchanged by potassium ions; If it is converted to 5A by calcium ion exchange, it has selective adsorption, and is widely used in the adsorption separation process, which can separate and purify liquids, mixed gases, and isomers. At present, zeolite molecular sieves have been used on a large scale to separate hydrogen, oxygen, oxygen-rich air, and rare gases. Zeolite catalysts are mainly used for petroleum refining, catalytic cracking of petroleum hydrocarbons, hydrocracking, hydrogenation of definitive hydrocarbons, and hydrogenation of olefins; Hydrogen isomerization, toluene disproportionation, production of synthetic fuels, phenotypic catalysis of hydrocarbons.

No! Molecular sieves in the usual sense are used to absorb water.

Please don't listen upstairs.

Based on two points: 1) the activity of ethylene oxide is too high, and the desiccant of molecular sieve inevitably contains some alkaline substances, which can catalyze the ring-opening polymerization of ethylene oxide, and dehydration with molecular sieve is likely to lead to ethylene oxide polymerization. 2) Ethylene oxide has a very low boiling point of only 10, and it is easy to remove water by rectification.