Grimsel colloid exercise : An international intercomparison exercise on the sampling and characterization of groundwater colloids
The Grimsel Colloid Exercise is an intercomparison project to evaluate both sampling and characterisation techniques, with emphasis on determining the colloid size distribution, by CoCo Club members. Colloid samples were produced by the following methods: 1) cross-flow ultrafiltration with production of membranes loaded with colloids; 2) tangential diaultrafiltration and production of colloid concentrates; 3) filtrates and 4) unfiltered water collected under controlled anaerobic conditions in either glass or plastic bottles. While shipping and storage may affect the colloid samples, as well as the composition of both unfiltered/filtered water and concentrate samples from this somewhat demineralised water, the major element composition of the fluid samples is comparable between groups. However, air contamination decreases the pH from 9.6 to about 8, while increasing the concentration of total inorganic carbon. The exercise differentiates the colloid samples produced on site from those obtained after transfer of the fluid samples to the laboratories. The colloid concentration and size distribution is determined by scanning electron microscopy, gravimetry, chemical analysis of fluid samples after micro/ultrafiltration and by transmission single particle counting. The colloid concentration is also evaluated by transmission electron microscopy, static and dynamic light scattering and by laser- induced photoacoustic spectroscopy.
Bibliographic Reference: EUR 12660 EN (1990) 70 pp., FS, ECU 7.50
ISBN: ISBN 92-826-1571-5
Record Number: 199011204 / Last updated on: 1994-12-01
Original language: en
Available languages: en