Two Types of Reverse Osmosis Membranes
Reverse osmosis purifies water by forcing it through a semipermeable membrane that filters out contaminants. The two types of reverse osmosis membranes commonly used in home water purification are the thin film composite and cellulose triacetate. Does this Spark an idea?
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Background
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Most reverse osmosis systems consist of an activated carbon pre-filter, the reverse osmosis membrane, a storage tank and the faucet to deliver the purified water.
Cellulose Triacetate
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The cellulose triacetate membrane can treat chlorinated water but is susceptible to bacterial contamination. This filter also only filters out about 93% of standard contaminants, according to Advanced Water Filters.
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Thin Film Composite
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Advanced Water Filters also reports that the thin film composite membrane filters out about 98% of standard contaminants and is less susceptible to bacteria. However, the thin film composite membrane is sensitive to chlorine and requires that a carbon filter pretreat the water to remove the chlorine.
Considerations
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According to Home Water Purifiers and Filters, the effectiveness of a reverse osmosis system depends on the quality of prefilter cartridges and the membrane. Lower-quality components reduce the performance of a water filter.
Membrane Replacement
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Home Water Purifiers and Filters suggests that a thin film composite membrane be replaced every 2 to 3 years. A cellulose triacetate membrane may require more frequent replacement.
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References
- Photo Credit water from tap image by Ruth Chesterman from Fotolia.com
