Chemical Sensors and Membranes in Automated

Environmental Monitoring and Wastewater Treatment

Flow Injection Analysis

Flow Injection Analysis (FIA) is a powerful flow-through technique for solution manipulation prior to detection. It allows inexpensive automation of chemical analysis, and is fast and economical with respect to sample and reagent consumption. Most of my research in this area has been focused on the theory and application of various flow injection systems.

The associated theoretical work involves the mathematical modeling and optimization of such flow systems. I am particularly interested in the application of FIA for the direct determination of environmental pollutants such as heavy metals (Cu, Cd, Pb, Zn, As, Sb, Hg), cyanide, ammonia and phenols in natural waters and industrial wastewaters. Volatile pollutants can be determined successfully in flow injection systems incorporating gas-diffusion or pervaporation cells, where the pollutants of interest are separated on-line prior to detection from a sample matrix usually containing suspensions, emulsions, surfactants or corrosive compounds.

 

Chemical Sensors

My interests in this area cover the development, study and application of three main classes of chemical sensors:

· electrochemical sensors such as amperometric and potentiometric (micro)electrodes and arrays of such electrodes.

· gas sensors such as micropellistors.

· optical chemical sensors (optodes) utilizing redox or complexation analytical reactions.

Micro chemical sensors allow the construction of portable chemical analyzers suitable for on-site environmental monitoring.

 

Membrane Extraction

Solvent extraction has been widely used in metal separation and concentration in the recycling of industrial metal resources and wastewater treatment processes. One of the most important problems associated with industrial solvent extraction is the large inventory of expensive extractants and solvents required. An alternative environmentally friendly and inexpensive approach for metal separation and concentration can be based on the use of liquid membranes. My research interests in this area are centered on the theory and application of membrane extraction involving PVC based polymer liquid membranes incorporating Aliquat 336 chloride or di-2-ethylhexyl-phosphoric acid as the liquid ion-exchangers. These membranes have shown promising results for the recovery of various metals ions such as Au(III), Cd(II), Cu(II), Pd(II) from their acidic aqueous solutions.

Selected Publications:

1. Wang, L., Cardwell, TJ, Luque de Castro, MD, Cattrall, RW, Kolev, SD, Talanta, 60, 1269, 2003.
2. Kolev, S.D., Sep. Sci. Technol., 38, 237, 2003.
3. Satienperakul, S.; Cardwell, T.J.; Cattrall, R.W.; McKelvie, I.D.; Taylor, D.M.; Kolev, S.D., Talanta, 62, 631, 2004.
4. Rupasinghe, T.; Cardwell, T.J.; Cattrall, R.W.; Potter, I.D.; Kolev, S.D.; Anal. Chim. Acta, 510, 225, 2004.
5. Amini, N.; Cardwell, T.J.; Cattrall, R.W.; Morrison, R.J.S.; Kolev S.D., Talanta, 63, 1069 , 2004.