What are the common color-changing desiccants? At present, the common color-changing silica gel desiccants include blue silica gel desiccant, cobalt-free orange silica gel desiccant, and cobalt-free blue silica gel desiccant.

Discoloration process of blue silica gel desiccant:

1. The main reason for the discoloration of blue silica gel desiccant (blue to red) is that it contains cobalt dichloride. Cobalt dichloride itself has the characteristic of changing from blue to pink due to water absorption. Toxic. Avoid contact with food and inhalation. If poisoning occurs, seek medical attention immediately.

The discoloration process of orange silica gel desiccant:

2. The main reason for the discoloration of the cobalt-free blue silica gel desiccant (yellow to red) is that it contains Congo red, which is rarely used at present. Congo red itself can be used as an acid-base indicator, the color range is 3.5 to 5.2, the basic state is red, and the acid state is blue-violet.

3. The main reason for the discoloration of the cobalt-free orange silica gel desiccant (orange to dark green) is that it contains methyl violet. The color of methyl violet will change due to the change of pH. It uses methyl violet to occur in the range of pH 0.13-0.5. Orange → dark green" principle.

The above is the introduction of ""What kinds of common color-changing desiccants"". For more information on desiccants, please visit: http://www.amingwei.com/