Activated carbon cloth - Flexzorb FM10

Flexzorb FM10 activated carbon cloth is ideal for the filtration of contaminants in museum fume cupboards.

It is in showcases and cabinets that high concentrations of harmful gases can be detected, such as acetic acids, volatile organic acids, formaldehyde from artworks and display materials (woods, adhesives and paints) and H2S, NO2 and SO2 from ambient air.

These harmful gases can damage the following artworks and materials:

• Metals and their alloys, especially lead and leaded bronzes, copper, iron, silver....
• Glass, enamels, glazes (glass disease)
• Calcareous ceramics (lacotrichite efflorescence)
• Mussels, snails and eggshells (Byne's disease)
• Leather, organic adhesives (formaldehyde hardening, red rot caused by SO2)
• Paper, books, graphics, textiles, paintings on canvas (increasingly acidic and brittle)
• Pigments (lead white)
• Plastics, e.g. cellulose nitrate (accelerated autocatalytic degradation caused by NOx)

Activated carbon cloth has the capacity to adsorb different amounts of acetic acid depending on the concentration of the acid in the air, per 100 g of cloth depending on the concentration (non-impregnated type):

• at 1000 ppmv: can adsorb 20 g
• at 10 ppmv: can absorb 7 g
• at 0,1 ppmv: can absorb 1 g
• at 0.01 ppmv: can absorb 0.25 g

It also adsorbs other volatile organic acids, H2S, NO2 and SO2, as well as formaldehyde and apolar gases.

This activated carbon fabric has a variety of lamination options to suit the specific needs of each application. Being composed of 100% activated carbon, it offers the highest possible protection against harmful substances and decontamination of artwork, furniture or wooden objects that are contaminated with pesticides or noxious gases. For exhibitions, if the black colour of the fabric is not desired, it can be covered with a thin decorative fabric to blend in with the surroundings.

Filtration of contaminants in fume cupboards is best achieved with activated carbon fabrics, as they offer a larger adsorption surface area than some activated carbon granules due to their fine fibres. The black fabric is made of 100% activated carbon and has very fine pores with an inner surface area of 900 - 1200 m²/g. Due to their large surface area, they offer the highest possible protection against harmful substances. For this reason, museums often prescribe activated carbon cloth in their loan conditions. Activated carbon cloth is the ideal solution for large surfaces, such as the back panels of display cases.

ACC (Activated Carbon Composite) is easy to use and cut but must be handled with care to avoid damage and corrosion on metallic and sensitive surfaces. In this case a neutral (non-reactive) cloth should be placed between the ACC and metal surfaces or exhibits and avoid contact of the ACC with skin, eyes, artwork, metals (such as aluminium and zinc), and other sensitive surfaces.

ACC can be lined with a variety of decorative fabrics. The most versatile type is ACC laminated on one side or on both sides with a non-woven fabric. Depending on your needs, you can coat the charcoal side or the non-woven side. ACC only crumbles slightly at the cut edges and can be worked like any fabric.

Activated carbon fabrics are also used to decontaminate furniture or wooden objects contaminated with pesticides (PCP, lindane...). The objects are packed in bags or covers made of these filter fabrics to ensure that harmful gases cannot enter the air in the room. Over the years, the objects are decontaminated. However, the fabric can only bind pollutants that have entered the gaseous phase. Therefore, this technique cannot decontaminate objects any faster than placing them in a well-ventilated space.

Some archives use activated carbon to filter contaminants from film canisters. Since the activated carbon fabric is powdered on the cut edges, for this application the pieces of fabric are sealed in dust-proof Tyvek.