The effect of cross-linkage on internal diffusion in Dowex-50 ion exchange resin
As far back as the time of Aristotle sand filters were used to purify water. However it was not until the time of Thompson and Way (1848), two English agricultural chemists, that the idea of actual exchange of ions was proposed. Ion exchange has been investigated extensively, resulting in applications to softening of water, purification of sugar, separation of compounds, recovery of metals, many pharmaceutical separations and many others. It has been proposed that the internal diffusion should be related to the internal structure of the ion exchange resin. The object of this research was to measure the internal diffusion and relate it to the cross-linkage of the resin. It was suggested by Dr. Theodore Vermeulen of the Chemical Engineering Department, University of California. He proposed that the external diffusion could be eliminated by having a high rate of flow in the column. By measuring the width of the zone formed, the rate constant could be found. The rate constant is proportional to the diffusion rate.
Ion exchange, Diffusion, Chemistry, Physical Sciences and Mathematics
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