https://orcid.org/0000-0002-2300-8158
![Sample our Physical Sciences journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/110819/TOC-Subject-Sample-2021-Physical-Sciences.jpg"})
ABSTRACT
The ammonia component represents a sizable portion of pollutants in mining wastewater (MW) and because of its high selectivity toward ammonia, a LEWATIT resin was tested in the batch adsorption using different masses with 22.7 mg/L NH3 − N and in the continuous adsorption using two fixed-bed columns. Also, resin regeneration was achieved using diluted HCl. The results show the adsorption follows Freundlich isotherm in the batch study and was characterized by both the Bohart–Adams and Thomas models in the fixed-bed column. HCl can be used to regenerate LEWATIT with efficiency 40% and 70% for the small and large column, respectively.
Nomenclature
| = | NH3−N concentration at breakthrough (mg/L) | |
| = | NH3−N concentration at equilibrium (mg/L) | |
| = | NH3−N concentration in elution solution at initial (mg/L) | |
| = | NH3−N concentration in elution solution at time t (mg/L) | |
| = | NH3−N concentration at initial (mg/L) | |
| = | NH3−N concentration at saturation (mg/L) | |
| = | NH3−N concentration at time t (mg/L) | |
| = | Rate constant in Bohart-Adams model (L/mg.min) | |
| = | Apparent desorption rate constant (1/min) | |
| = | Freundlich constant related to the adsorption capacity ((mg/g).(L/mg)1/n) | |
| = | Langmuir equilibrium constant of the free energy of adsorption (L/mg) | |
| = | Volumetric mass transfer coefficient (1/min) | |
| = | Rate constant in Thomas model (L/mg.min) | |
| = | Mass of adsorbent (g) | |
| = | Adsorbed NH3 mass (mg) | |
| = | Desorbed NH3 mass (mg) | |
| = | Total NH3 mass (mg) | |
| = | Freundlich constant of the desorption intensity (dimensionless) | |
| = | Number of samples collected during continuous adsorption (dimensionless) | |
| = | Saturation concentration in Bohart-Adams model (mg/L) | |
| = | Volumetric flowrate of real wastewater (L/min) | |
| = | Adsorption capacity at equilibrium (mg/g) | |
| = | Adsorption capacity at breakthrough (mg/g) | |
| = | Maximum adsorption capacity (mg/g) | |
| = | Adsorption capacity at saturation (mg/g) | |
| = | Universal gas constant (J/mol K) | |
| = | Separation factor in Langmuir isotherm (dimensionless) | |
| = | Time (min) | |
| = | Time to achieve breakthrough (min) | |
| = | Time at which elution is terminated (min) | |
| = | Time to achieve maximum NH3−N concentration during desorption (min) | |
| = | Time to achieve saturation (min) | |
| = | Temperature (K) | |
| = | Linear velocity of real wastewater (cm/min) | |
| = | Volume of adsorbate (L) | |
| = | Bed depth (cm) | |
| = | Density of real wastewater (mg/cm3) | |
| = | Porosity of column (dimensionless) |
Acknowledgements
Portions of this work were funded by the Natural Sciences and Engineering Research Council of Canada.