The orange silica gel is also known as cobalt-free allochroic silica gel, which is particle of spherical or irregular block shape, with orange-yellow appearance, and whose main component is silica; the color varied with the humidity, it is orange-yellow without being damp, and with the increase of moisture adsorption, it gradually becomes green and then dark green; besides property of blue gel, it has advantages of cobalt chloride free, non-toxic and harmless; it is environmental protection product newly developed.
