The isotherm of adsorption and desorption of coconut-based activated carbon for domestic tobacco was determined by low temperature nitrogen adsorption method, BET method was used to calculate its specific surface area and pore volume, and density function theory was used to calculate its total pore distribution. The surface morphology of activated carbon was observed by scanning electron microscope. Finally, seven kinds of samples whose structural parameters meet the requirements of the experimental gradient are determined. The specific surface area of the sample ranges from 700-1400m2/g, and the particle size ranges from 40-60, 60-80 and 80-100 mesh. All the samples are dominated by micropores, and the percentage of micropores is more than 80%.Combined Equations (5) and (10) can calculate the total amount of Pb and 21Bi atoms in activated carbon after adsorption for any length of time (i.e., the total number of activated carbon Y).Let n=0 in Equation (10), then the accumulation and attenuation of total atomic amount of 2Pb and 2Bi (total number of activated carbon Y) after the removal of activated carbon can be calculated in Equation (10).In fact, if thin layer activated carbon is used, the value of N should be equal to the product of the adsorption coefficient of activated carbon and radon concentration, while the radon adsorption coefficient of activated carbon mainly depends on the type of activated carbon and is affected by temperature, humidity and other factors.
When the radon adsorption coefficient of activated carbon is constant,n is proportional to the concentration of radon. In this case, Equation (10) represents the functional relationship among the total number of activated carbon V, radon concentration and adsorption (or exposure) time. Therefore, the concentration of radon in the environment can be calculated according to the total number of activated carbon and adsorption time.Simulation calculation and result analysis of total number of activated carbon According to Equations (5) and (10), a computer program can be written to calculate the relationship between the total number of Y in the process of radon adsorption on activated carbon and the relationship between the total number of Y after the removal of activated carbon and the change of time.https://www.activated-carbon-pellets.com
In order to verify the accuracy of the simulation calculation, two 12g activated carbon bags thickness of activated carbon ~ 1.5cm) were put into the container containing uranium ore, and then taken out after radon adsorption for 30 min and 85 min. After continuous measurement, the change curve of total Y number of activated carbon over time could be obtained.granular activated carbon suppliers
According to the adsorption duration used in the experiment and the appropriate value of n (in the calculation process, when the adsorption duration is 30 min, n=480