Abstract
The impact of solution pH on the kinetics of adsorption and adsorption-reaction combination of phenol and o-cresol on Granular Activated Carbon (GAC) was evaluated at room temperature (21°C). Batch experiments were performed under oxic and anoxic conditions at pH values of 3, 7, and 11. The results showed that the equilibration time for physical adsorption increased with the increase in pH and occurred in the time range of (7.5-11) days for the adsorption-reaction combination toxic cases). The polymerization reactions lagged by about 10 h under all of the pH values. Diffusivity coefficients in the oxic cases increased inversely with pH while the highest difference between oxic and anoxic diffusivities was observed at neutral pH. The homogeneous surface diffusion model (HSDM) predicted accurately the anoxic batches and deviated from the oxic data under all pH conditions. Under controlled dissolved oxygen and pH conditions, the isotherm and batch equilibrium capacities matched with maximum deviation of 4%. The effect of solution pH on the rate of the DO-induced enhancement was found to follow a simplified form of self retardant reaction model. The aforementioned model showed strong predictive capability for the formation of polymers with time.
| Original language | English |
|---|---|
| Pages (from-to) | 217-230 |
| Number of pages | 14 |
| Journal | Journal of Hazardous Materials |
| Volume | 49 |
| Issue number | 2-3 |
| DOIs | |
| State | Published - Aug 1996 |
Bibliographical note
Funding Information:The authors would like to thank the Research Institute and the Department of Civil Engineering, King Fahd University of Petroleum and Minerals, for providing support to this research.
Keywords
- Activated carbon
- Dissolved oxygen
- Kinetics
- Modeling
- Phenolic
- Polymer
- ph
ASJC Scopus subject areas
- Environmental Engineering
- Environmental Chemistry
- Waste Management and Disposal
- Pollution
- Health, Toxicology and Mutagenesis