The FilmTec™ LC LE Pro-4040 Low Pressure Brackish Water RO Membrane
The Reverse Osmosis (RO) Membrane forms the heart of a Reverse Osmosis System. It consists of a semi-permeable membrane that allows water molecules to pass through but captures 99.8% of all other particles in the water. The RO Membrane removes bacteria, viruses, minerals, heavy metals, and pesticides from the water.
FilmTec™ LC LE PRO-4040 Elements deliver high-quality water at low pressure at harsh water conditions, using DuPont’s innovative, proprietary technology for low energy commercial applications. DuPont’s fully automated element production enables the most consistent products in the industry that minimizes the total cost of ownership of water treatment systems.
The FilmTec™ LC LE Pro-4040 RO Membranes are designed to work with low-pressure situations with medium size commercial or industrial applications, such as DI (Deionized) water, Laboratories, Hospitals, Battery water, aquariums, offices, ice makers, restaurants, etc. The LC LE Pro-4040 membranes are rated to handle source waters that have a TDS of 2000ppm or lower (<2000ppm).
FilmTec™ LE LC Pro-4040Elements features:
- Key Features l l LC LE PRO-4040 delivers high-quality water at low pressure at harsh water conditions, using DuPont’s innovative, proprietary technology for low energy applications.
- Industry leading active area (94 sqft) which provides less fouling due to lower operating flux while still achieving higher flow.
- Offers high salt rejection at low pressure in harsh water conditions.
- Provides most effective cleaning performance, robustness and durability due to its widest cleaning pH range (1– 13) and chemical tolerance. Typical Properties
Key Applications
- Light industrial applications requiring good permeate quality.
- Harsh feed water condition.
- Drinking water– Refilling stations, Bottling plants, Hotels, Schools, Institutions etc

FilmTec™ LC LE Pro-4040 RO Membrane Specifications:

- Average Permeated Flow (Product Water): 2300GPD / 8700LPD*
- Stable Rejection Rate: 99.5%
- Minimum Rejection Rate: 99%
- Membrane Type Polyamide: Thin-Film Composite
Testing Conditions for Specification Rating:
Testing Pressure: 125psi (8.5 bar)
Testing Solution Temperature: 25°C
Testing Solution Concentration (NaCl) - 2000ppm
PH Value of Testing Solution: 8
Recovery Rate of Single Element: 15%
Keep in Mind
The average permeated (product) water flow is based on test water consisting of 2000ppm of only salt (NaCl) which is one of the easier minerals for the RO membrane to handle. Other elements such as hardness (lime, Calcium/Magnesium) are harder for the membranes to remove, and may reduce the average permeate rate of the RO membrane.
Other elements such as source water pressure and the Total Dissolved Solids (TDS / Total Mineral Content) level can also have an influence on the permeate level produced by the membrane. Typically in real-world situations with municipal or non-municipal source water quality, you will not get the same quality and/or pressure as the "testing conditions" used to rate the membranes. So, in most applications, you will likely find that the actual permeate flow rate of the RO membrane is between 30 to 80% of what has been rated.
Operating Limits for the Membrane:
Maximum Operating Temperature: 113°F (45°C)
Maximum Operating Pressure: 600 PSI (41 bar)
Maximum Feed Flow Rate: 16 GPM (3.6 m3/h)
pH Range, Continuous Operation: 3 – 10
pH Range, Short-Term Cleaning: (30 min.)b 2 – 12
Maximum Feed Silt Density Index (SDI): 5
Free Chlorine Tolerance: < 0.1 ppm