Saturation indicator for formaldehyde absorption by active carbon and preparation method thereof

The invention relates to a saturation indicator for formaldehyde absorption by active carbon. The saturation indicator comprises the following components by weight percentage: 70-98.5% of active carbon, 0.5-20% of a water absorption expansion material, and 1-20% of a water production material. The water production material and formaldehyde are reacted to generate water, the volume of the water absorption expansion material is expanded after water absorption, the indicator can timely and effectively indicate inactivation of the active carbon, and is convenient for timely replacing, the indicator uses active carbon powder which does not have market value, increases economic benefit, reduces energy consumption, reduces environment pollution, does not generate chemical pollution, and has the advantages of safety and environmental protection. 本发明的活性炭吸附甲醛饱和指示剂，包括以下重量百分比的组分：活性炭70％～98.5％，吸水膨胀材料0.5％～20％，产水材料1％～20％；所述产水材料与甲醛反应生成水，所述吸水膨胀材料吸水后体积膨胀。该指示剂能够及时有效地指示活性炭失活，便于及时更换；而且该指示剂利用了没有市场价值的活性炭粉末，提高经济效益，降低能耗，减少环境污染；无化学污染，安