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Comparative Study of 4-Aminophenol Removal from Aqueous Solutions by Emulsion Liquid Membranes Using Acid and Basic
Gerardo León1, Juliana Otón1, Asunción María Hidalgo2
1Departamento de Ingeniería Química y Ambiental, Universidad Politécnica de Cartagena, 30206 Cartagena, Spain.
Membranes
|December 23, 2022
Summary
This study demonstrates effective removal of 4-aminophenol (4AP), an environmental pollutant, from water using facilitated transport in emulsion liquid membranes. Optimized conditions and the Behnajady model accurately predict 4AP removal efficiency.
Area of Science:
- Environmental Chemistry
- Separation Science
Background:
- 4-aminophenol (4AP) is a significant environmental pollutant originating from industrial processes and pharmaceutical degradation.
- Effective removal strategies are crucial for mitigating the environmental impact of 4AP.
Purpose of the Study:
- To comparatively study 4-aminophenol (4AP) removal from aqueous solutions using acid and basic type 1-facilitated transport in emulsion liquid membranes.
- To optimize experimental conditions for enhanced 4AP removal and analyze the removal kinetics.
Main Methods:
- Emulsion liquid membrane separation utilizing acid and basic facilitated transport.
- Systematic investigation of experimental parameters including stripping agent concentration, surfactant concentration, stirring rate, and volume ratios.
- Kinetic analysis using first order, second order, Behnajady, and Avrami models.
Main Results:
- The Behnajady model provided an excellent fit for the removal kinetics, enabling calculation of initial removal rate and maximal removal conversion.
- Optimized experimental conditions significantly improved 4AP removal efficiency.
- Facilitated transport mechanisms were elucidated by considering the acid/basic properties of 4AP and hydrogen bonding of its ionized products.
Conclusions:
- Emulsion liquid membranes with facilitated transport offer an effective method for removing 4-aminophenol (4AP) from aqueous solutions.
- The Behnajady model accurately describes the removal kinetics, and experimental optimization is key to achieving high removal rates.
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