Microwave heating can produce good effects in the preparation and modification of activated carbon (S2. Microwave modification, many backwater hole is opened, the distributed capacitance change obviously, promoting the improvement of the adsorption. The microwave power and irradiation time are key determinants of modified activated carbon adsorption performance. On the mechanism of microwave carbonization and activation, it is generally believed that
Plant waste is mostly made of plant fiber raw materials, in the plant body under the action of capillary, modified solution absorbed by material whole fully, between fiber is filled with the subtle space, make the dry material volume expansion after soaking wet, and reaction. Because of the water in the raw material, modified solution constitute a polar molecule, with a strong absorption of microwave dielectric properties,Therefore, polar molecules collide and rub violently with microwave frequency, generating a large amount of heat, which makes water and modified solution volatilize rapidly, and generate steam pressure, which explodes out from the inside of the raw material to the outside. This sharp action makes the fiber space of the raw material expand and produce sharp drying.In this way, the raw material has a more obvious pore structure and a larger internal specific surface area than before microwave irradiation. Compared with the traditional heating method, the mechanism of microwave in the preparation process of activated carbon is completely different.It shows its unique advantages: high efficiency, energy saving, uniformity, selectivity, low pollution, high thermal efficiency, low energy consumption, simple process and equipment and small footprint, conducive to automation, low carbon loss, and recovery of useful substances.Microwave method, microwave method is not independent of the physical method and chemical method of the preparation of activated carbon, but on the basis of the physical method and chemical method instead of the traditional heating method, but it has a very significant effect.
https://www.dxdcarbon.com/
Microwave refers to the electromagnetic radiation located between far-infrared and radio waves in the electromagnetic spectrum, with a frequency range of 300MHz to 300GHz and a wavelength of 1m to 1mmMicrowave generates "internal friction heat" through high frequency reciprocating motion of dipole molecules in the heated body, which raises the temperature of the material. It does not require any heat conduction process, and has the characteristics of high efficiency, selectivity, non-contact, integrity, uniformity, quick start and stop, and easy operation Studies have shown that activated carbon can effectively absorb microwave energy and make the temperature rise to 110o℃5' within a few minutes.Air velocity of empty tower :U= 1.0m /s.OriginalIts adsorption performance mainly depends on several main material parameters and process parameters on it [8. Material parameters including carbon adsorption porosity, thickness of honeycomb structure and the content of carbon; process parameters including fluid flow rate and concentration of the adsorption properties of adsorption, can adsorption depends on the carbon structure and adsorption properties of features such as molecular weight). The curve is one of the main performance characterization of adsorption, adsorption is the adsorbate concentration ratio before and after the change over time of a function [9 '. This ratio is 0.95, the amount of adsorption properties of adsorption is called penetration capacity. Penetration capacity depending on the fluid flow rate, the concentration of the adsorbate and honeycomb carbon component contentwood based activated carbon manufacturer
Factors such as [10. For honeycomb activated carbon, the wall thickness is a very important parameter, by changing the wall thickness to improve its adsorption efficiency. Under the same porosity, thickness increases, the honeycomb carbon content per unit volume also will increase, which can improve the adsorption capacity. This is because the wall thickness increases, the fluid channel in the cellular cross-sectional area reduced, so the real surface or volume flow rate will increase. At the same time, the contact between adsorbate and carbon efficiency will, there is a balance between the two. Under the given conditions, the balance will determine adsorption increase or decrease. If the adsorbate at higher the diffusion rate diffuses to the inside of the honeycomb wall, and the empty adsorption site can be continuously adsorbed, so the thick-walled honeycomb should have better adsorption efficiency and adsorption capacity"Determination of air velocity and cross-sectional area of empty towerThe empty tower gas velocity is the velocity of gas passing through the entire cross section of the adsorber.The selection of air velocity not only directly determines the size and pressure drop of the adsorber, but also affects the adsorption efficiency.