Antimony Trioxide

antimony trioxide is a fine white powderAntimony trioxide, also known as antimony oxide or Sb2O3, is the most widely produced compound of elemental antimony. The nations that produce the most antimony trioxide are China, South Africa, Bolivia, Russia, Tajikistan, and Kyrgyzstan. Typical applications for antimony trioxide include flame retardant synergist for use in plastics, rubber, paints, paper, textiles, and electronics; polyethylene terephthalate polymerization catalyst; a clarifying agent for glass; an opacifier for porcelain and enamel; and a white pigment for paint. When used as a flame retardant, antimony trioxide is often used in combination with halogenated compounds. Antimony trioxide is used as a synergist to enhance the activity of the halogenated flame retardant. In the absence of antimony trioxide about twice as much halogenated compound would be needed to reach the same level of flame retardancy.

Four grades of antimony trioxide

Amspec is proud to offer four grades of antimony trioxide.

Amspec KR grade antimony trioxide is suitable for almost all standard flame retardant and additive applications.

Amspec LTS grade antimony trioxide is similar in purity to Amspec KR, but is specifically for applications where you need the tinting strength of the antimony trioxide to be minimized. This low tinting strength grade means you can use less pigment to achieve your desired color specification.

Amspec Select is a higher purity grade of antimony trioxide compared to Amspec KR. Amspec Select can be used in flame retardant applications where lead levels are of concern, like in Europe to meet the requirements of the RoHS Directive. The Select grade is also used as a catalyst in PET production.

Amspec’s highest purity antimony trioxide product is Amspec SP. Amspec SP is suitable for highly lead and/or arsenic sensitive applications.

Product information

Amspec KR, Amspec LTS, Amspec Select, and Amspec SP grades of antimony oxide are white, odorless, crystalline powders.

Amspec offers flexible packaging options for all grades of our antimony trioxide. Standard packaging is available in 50 lb or 25 kg bags and in 2,000 lb or 1,000 kg supersacks. Amspec can provide custom packaging upon request.

Amspec brand antimony trioxide can be dampened with a variety of media including, but not limited to, ethylene glycol, diisodecyl phthalate (DIDP), and mineral oil.

KR LTS Select SP
Sb2O3 (min) 99.5 % 99.5 % 99.8 % 99.9 %
Sb+3 (min) 83.6 % 83.6 % 83.8 % 83.9 %
Arsenic, As (max) 0.10 % 0.10 % 350 ppm 20 ppm
Lead, Pb (max) 0.10 % 0.10 % 425 ppm 20 ppm
Iron, Fe (max) 60 ppm 60 ppm 40 ppm 15 ppm
Selenium, Se (max) 30 ppm 30 ppm 10 ppm
Bismuth, Bi (max) 30 ppm
Copper, Cu (max) 30 ppm
Tin, Sn (max) 20 ppm
Sodium, Na (max) 100 ppm
Nickel, Ni (max) 30 ppm
Average Particle Size 0.9 – 1.3 μ 1.6 – 3.0 μ 0.2 – 2.0 μ 2.0 – 5.0 μ