ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Electric Fields in Zeolites: Fundamental Features and Environmental Implications

Christopher J. Rhodes

Fresh-lands Environmental Actions, Caversham, Berkshire RG4 5BE, UK

E-mail: cjrhodes@fresh-lands.com

Abstract: A critical review of zeolites and their use in practical applications is presented. Specificallyconsidered are their role as media for selective light-induced oxidations using molecular O₂, and the relationship between this phenomenon and the surface electric fields that exist in zeolites. Methods for the determination of the strength of zeolite surface fields are discussed using sorbed molecules such as CO (with IR detection), spin-probes, di-tert-butyl nitroxide, and NO (measured using EPR spectroscopy). Relationship between the surface fields and molecular reorientation energetics for free radicals sorbed in zeolites, obtained using muonium as a spin-label, is explored. Finally, results obtained from exposing the naturally occurring zeolite, clinoptilolite, to high energy electrons as a means for activating materials toward selective removal of radioactive caesium and strontium cations from wastewaters of nuclear power plants are presented.

Keywords: zeolites – muon – photooxidation – surface electric field – radioactive waste – EPR

Full paper is available at www.springerlink.com.

DOI: 10.1515/chempap-2015-0160

Chemical Papers 70 (1) 4–21 (2016)