PHOTOREACTIONS OF REVERSIBLE BLEACHING OF DYES ADSORBED ON GLASS CAPILLARIES
Abstract
Absorbed methylene blue on microporous glass shows initially reversible bleaching under irradiation and regeneration with molecular oxygen in the presence of organic and inorganic bases. During the irradiation as a result of heating by the light, part of the dye monomer is converted to dimer which is not reversibly bleached. Photobleaching of the adsorbed dye occurs at low temperature (-180, -70 deg C) significantly more weakly than at room temperature. Capillary condensed oxygen at low temperature has almost no regenerating effect on the leucoform of the dye. Traces of iron present in the microporous glass do not influence the bleaching of adsorbed methylene blue, and the artificial introduction of iron facilitates not the bleaching process, but only the dimerisation of the dye under the action of light. The reversible photobleaching and regeneration of adsorbed dibenzypyrene-quinone on microporous glass in the presence of organic bases was observed. Additional experiments show the part played by surface OH groups on the porous glass and other adsorbents in the photoreduction of methylene blue.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1968
- Accession Number
- AD0682883
Entities
People
- A. V. Karyakin
Organizations
- United States Army Biological Warfare Laboratories