Sterlitech™ Silver Membranes: Cleaning Guidelines

Sterlitech’s Silver Metal Membrane Filters can be cleaned and reused repeatedly. The membranes should be cleaned immediately after each use, and handled carefully to avoid membrane punctures and tears. Various cleaning procedures can be used, depending on the nature, type, and degree of contamination. There are four effective cleaning methods outlined below, that can be used to clean Sterlitech’s silver metal membrane filters.

Chemical Cleaning

Immerse in a strong alkaline solution, a solvent, or an acid. Do not immerse in nitric acid, sulfuric acid, or cyanide solutions.

Ignition Cleaning

Place the silver metal membrane filter in a laboratory muffle furnace for approximately ½ hour to effectively remove organic contaminants from the membrane. Do not exceed the following temperatures.

Retention Rating (microns)	Maximum Temperature
	°C	°F
5.0	550	1020
3.0	400	750
1.2	350	660
0.8	300	570
0.45	300	570
0.2	250	480

Combination Cleaning

A combination of chemical and ignition cleaning may be the best method to completely regenerate the membrane. Immerse in a 10 percent concentration of hydrofluoric acid for ten minutes, followed by ignition cleaning in a muffle furnace, following the guidelines given above. This can allow for reuse of membrane up to 10 times.

Ultrasonic Cleaning

Low intensity ultrasonics can be used to lean the silver metal membrane. The cleaning intensity and time will depend on the degree and type of contamination encountered. Do not use high intensity ultrasonics.