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Fastek CTA Cellulose Triacetate RO Membrane Elements

Product Information

CTA (Cellulose Triacetate) RO Membrane*

Fastek™ Cellulose Triacetate Membrane is a proprietary formulation that combines the high flow and high rejection properties of thin-film composite membranes with the chlorine tolerance and price advantage of cellulosic membranes and more chemical stability than competitive brand cellulosic membranes.


Benefits of CTA Membrane

  • High Rejection Unique CTA membranes formulation typically yields tap water total dissolved solids (TDS) rejections of 94-97%.
  • Superior Product Water Flow Microthin CTA membrane structure produces enhanced product water flow and minimizes loss of performance with time.
  • Chlorine Tolerance Many water supplies are chlorinated. Systems using chlorine-sensitive membranes must incorporate a chlorine removal medium, such as activated carbon, prior to contact with the membrane, to avoid damaging the membrane or impairing its performance. With chlorine tolerant cellulosic membranes, activated carbon postfilters can be employed to permit disinfection within the membrane and to allow carbon to treat only the product water (about 1/5 to 1/10 the quantity of the feedwater).
  • Chemical Stability A proprietary formulation allows Fastek CTA membranes to operate on water with a pH up to 9, higher than any cellulosic membrane in the industry.



Fastek sepralators are used primarily in tap water reverse osmosis systems. Osmonics® supplies many of the top systems manufacturers with reverse osmosis elements, and Osmonics spiral-wound elements are also available as replacements for most popular configurations.

Laboratory and commercial elements in various flow rates and configurations are also available.

Standard Features

Proprietary Pull-Ring and Brine Seal for easy
element removal.

Anti-Telescoping Device with O-ring(s) is
standard feature.


  • Polyethylene Brine Steel Provides superior feed-to-brine sealing-prohibits seal from flipping inside housing.
  • Anti-Telescoping Device (ATD) Prevents the natural tendency of spiral-wound elements to telescope.
  • Self-Centering ATD Lead end acts as a centering device to assist in positive engagement of product adapter in housing-eliminates hunting.
  • Proprietary Patented Pull-Ring Makes element removal a snap - eliminates the need for special tools ( on single product adapter models).
Cross section of a Fastek Reverse Osmosis Element
Product water flows spirally in product water carrier,last layer
contacts holes in product water tube for exit to collection system

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