We made activated carbon by carbonizing burreoxam, sludge, etc., so what is the method of calculating the adsorption capacity and adsorption capacity of the activated carbon?
Measuring BET surface or methylene blue adsorption of another tracer. Will depend on the actual task of adsorption
Adsorption of components (adsorbate) from solution by an adsorbent is conceptually similar to moisture adsorption on a solid. In that case adsorption is dependent on water activity (aw = % relative humidity/100). In an analogous way, sorption capacity for a dissolved component depends on concentration.
The obvious experimental approach is to immerse an known amount of adsorbent into an excess of adsorbate solution at different initial adsorbate concentrations. After equilibration is complete (to assess by a time experiment) an aliquot of the (clarified) solution is analysed for equilibrium adsorbate concentration. From the result the amount of adsorbed material is calculated.
The results can be analysed by one of the existing sorption isotherm models, i.e. the relationship between amount of adsorbed material (x) and equilibrium concentration (c). The simplest one is the empirical Freundlich isotherm: log (x/m) = (1/n) log (k/c), with m = the amount of adsorbent, 1/n = slope, and k = a constant. More sophisticated models are those by Langmuir and BET.
In order to assess the quality of your experimental adsorbent I recommend to compare its performance to a commercial adsorbent, e.g. active charcoal.
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