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Contribution to the study of the conductivity of high purity water; Contribution a l'etude de la conductivite de l'eau de haute purete

Abstract

In this work a study is made more particularly of two points: the production of high purity water and the estimation of this purity by means of conductivity measurements. As far as water purification is concerned it is observed that the de-ionisation produced by ion exchange resins in mixed beds leads to a water having a lower conductivity than that obtained by distillation. This low conductivity however, measured at the column exit before the water comes into contact with air is not stable. In fact the carbon dioxide in the water gives rise to an equilibrium with production of the ions HCO{sub 3}{sup -}, CO{sub 3}{sup --}. These ions are retained during the passage of the water through the resins. They reappear again at the column exit as a result of the displacement of the hydration equilibrium of CO{sub 2}; because of this the conductivity of the water increases with time. The water obtained by successive distillations does not behave in the same way because no carbon dioxide is present. Distillation is however a costly purification process on an industrial scale, especially if large quantities of water have to be treated. The measurement of these low conductivities is very delicate.  More>>
Authors:
Nens, Ch [1] 
  1. Commissariat a l'Energie Atomique, Saclay (France). Centre d'Etudes Nucleaires
Publication Date:
Jul 01, 1964
Product Type:
Technical Report
Report Number:
CEA-R-2633
Resource Relation:
Other Information: 21 refs
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ACID CARBONATES; CALIBRATION; CARBON DIOXIDE; DISTILLATION; ELECTRIC CONDUCTIVITY; ELECTRIC POTENTIAL; ION EXCHANGE MATERIALS; PH VALUE; PURIFICATION; RESINS; TEMPERATURE DEPENDENCE; TEMPERATURE MEASUREMENT; TIME DEPENDENCE; WATER
OSTI ID:
20650650
Research Organizations:
CEA Saclay, 91 - Gif-sur-Yvette (France)
Country of Origin:
France
Language:
French
Other Identifying Numbers:
TRN: FR05R2633090263
Availability:
Available from INIS in electronic form
Submitting Site:
FRN
Size:
72 pages
Announcement Date:
Nov 28, 2005

Citation Formats

Nens, Ch. Contribution to the study of the conductivity of high purity water; Contribution a l'etude de la conductivite de l'eau de haute purete. France: N. p., 1964. Web.
Nens, Ch. Contribution to the study of the conductivity of high purity water; Contribution a l'etude de la conductivite de l'eau de haute purete. France.
Nens, Ch. 1964. "Contribution to the study of the conductivity of high purity water; Contribution a l'etude de la conductivite de l'eau de haute purete." France.
@misc{etde_20650650,
title = {Contribution to the study of the conductivity of high purity water; Contribution a l'etude de la conductivite de l'eau de haute purete}
author = {Nens, Ch}
abstractNote = {In this work a study is made more particularly of two points: the production of high purity water and the estimation of this purity by means of conductivity measurements. As far as water purification is concerned it is observed that the de-ionisation produced by ion exchange resins in mixed beds leads to a water having a lower conductivity than that obtained by distillation. This low conductivity however, measured at the column exit before the water comes into contact with air is not stable. In fact the carbon dioxide in the water gives rise to an equilibrium with production of the ions HCO{sub 3}{sup -}, CO{sub 3}{sup --}. These ions are retained during the passage of the water through the resins. They reappear again at the column exit as a result of the displacement of the hydration equilibrium of CO{sub 2}; because of this the conductivity of the water increases with time. The water obtained by successive distillations does not behave in the same way because no carbon dioxide is present. Distillation is however a costly purification process on an industrial scale, especially if large quantities of water have to be treated. The measurement of these low conductivities is very delicate. The method employed makes use of a direct current and gives reproducible results if care is taken to exclude interfering electric fields by screening the apparatus. (author) [French] Au cours de ce travail nous etudions plus particulierement deux points: l'obtention d'eau de haute purete et l'estimation de cette purete grace a la mesure de sa conductivite. En ce qui concerne la purification de l'eau nous constatons que la deionisation effectuee par les resines echangeuses d'ions en lits melanges conduit a l'obtention d'une eau de conductivite plus faible que celle recueillie par distillations. Mais cette faible conductivite, mesuree a l'abri de l'air immediatement a la sortie de la colonne, n'est pas stable. En effet, dans l'eau, le gaz carbonique donne lieu a l'etablissement d'un equilibre avec apparitions d'ions HCO{sub 3}{sup -}, CO{sub 3}{sup --}. Ces ions sont retenus au cours du passage de l'eau sur les resines. Il en apparait de nouveau a la sortie de la colonne par deplacement de l'equilibre d'hydratation du CO{sub 2} si bien que l'on constate une augmentation en fonction du temps de la conductivite de cette eau. L'eau obtenue par distillations ne presente pas cette particularite car elle est exempte de gaz carbonique. Neanmoins la distillation est un procede de purification co eux a l'echelle industrielle surtout si les quantites d'eau a traiter sont importantes. La mesure de ces faibles conductivites est delicate. La methode de mesure utilisant le courant continu donne des resultats reproductibles a condition de se proteger des champs electriques parasites par un blindage approprie de l'appareillage. (auteur)}
place = {France}
year = {1964}
month = {Jul}
}