Dynamic Characteristics for Adsorption of Organic Substances in Wastewater on Activated Carbon by Shallow Bed Technique

Abstract

Dynamic characteristics for the adsorption of organic substances in wastewater on activated carbon was studied by using a shallow bed technique.Overall capacity coefficients, K_La, were calculated by the breakthrough curves obtained from the passing of wastewater through a shallow bed, packed with 2g activated carbon, at room temperature.
The effects of linear velocity of flowing wastewater through the bed, particle size and kind of activated carbon on K_La were tested.
The experimental results showed that linear velocity does not exert an influence on K_La in the range studied, suggesting that intraparticle pore diffusion resistance is the rate controlling rather than liquid film diffusion resistance.
When sieved activated carbon from coal was used, the correlation between mean particle size of activated carbon, d, and K_La was expressed by the following equation. K_La=53(d)^-1.6(1/hr). Both K_La and the amount of adsorbed organic substances on activated carbon from coal are superior to those from coconut.
Measurement of K_La of a ctivated carbon from four commeracial coals revealed that K_La depends greatly on the particle size of activated carbon. It was also found that K_La increases when organic substances, whose molecular weight being more than 30000, are removed.