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.
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.
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 thatHigh-quality granular activated carbon must have good adsorption performance and strength.
Like powdery activated carbon, the adsorption performance of granular activated carbon depends largely on the characteristics of pore structure. The adsorption performance index can be analyzed and characterized by different methods, such as the decolorization performance of activated carbon expressed by methylene blue. Other performance indexes include iodine adsorption value, caramel decolorization rate, etc.
The pore structure characteristics and specific surface area of activated carbon are usually obtained by measuring nitrogen adsorption isotherm at low temperature with adsorption apparatus.
For the gas phase adsorption, the size of the gas molecules is usually less than 1. ONM, the use of microporous activated carbon;
For liquid-phase decolorization refining, due to the large size of the liquid molecules, it is necessary to use activated carbon with developed mesopore.
Activated carbon has a large specific surface area and a particularly developed micro-pore structure, which is the main reason for its strong adsorption capacity and large adsorption capacity.Under these conditions, the COD removal rate reached 78.6%, the BOD /COD value increased from 0.168 to 0.353-0.403, and the biodegradability was greatly improved.https://www.dxdcarbon.com/
If Ho is added in three times and the interval time is 10min, the COD removal rate will increase from 78.6% to 80.3%. Therefore, it can be seen that H0: batch addition will further improve the reaction effect.
After Fenton oxidation treatment, wastewater and activated carbon adsorption, this topic activated carbon adsorption experiments using single factor method, examines different PH, activated carbon adsorption dosing quantity and the influence of adsorption time of wastewater COD removal rate, the results show that after Fenton oxidation treatment without having to adjust PH value, according to the 20 g/L after adding the activated carbon reaction 3 h at room temperature, COD removal rate was 47.3%,, BOD/COD value of 0.438 to 0.625.wholesale activated carbon pellets
The research in this paper has laid a theoretical foundation and provided an experimental basis for the practical application of Fenton oxidation and activated carbon adsorption in the pretreatment of natural gas purification maintenance wastewater in UASB reactor.