Study On Removing Formaldehyde In Indoor Air

The objective of the paper is to remove the indoor formaldehyde and purify the indoor air. The concentration of indoor formaldehyde was determined by the way of MBTH spectrophotometry and the removal efficiency of indoor formaldehyde by using Copper sulfate,Silver nitrate and Tea water with the way of chemisorption. The conclusions were as follows:(1) The effects of removing formaldehyde by copper sulfate and silver nitrate were very obvious. Besides, for copper sulfate and silver nitrate, the influence factors and trend to removal effect were the same.a) The removal of formaldehyde was enlargement with the increasing of the concentration of copper sulfate (silver nitrate). When the concentration of copper sulfate was 5.0g/L (the concentration of silver nitrate was 0.3g/L), the effects of removing formaldehyde reached to the best; then lower as the increasing of the concentration.b) The pH of copper sulfate (silver nitrate) bigger, the effects of removing formaldehyde better. When the pH of copper sulfate was 13.42 (the pH of copper sulfate was 12.47), the removal of formaldehyde reached to the best.c) When the chelon was different, the removal of formaldehyde was different, neither. For copper sulfate, the removal of formaldehyde, using potassium sodium tartrate as the chelon was better than using EDTA; but it was opposite for silver nitrate;d) When the concentration copper sulfate was 5.0g/L, pH= 13.42 and the chelon was potassium sodium tartrate, the removal of formaldehyde for 2.0mg/L and 10.Omg/L formaldehyde were 77.21% and 86.54%, respectively;e) When the concentration silver nitrate was 0.3g/L, pH= 12.47 and the chelon was EDTA, the removal of formaldehyde for 2.0mg/L and 10.Omg/L formaldehyde were 72.21% and 92.69%, respectively. (2) The removal of indoor formaldehyde was effective and steady, thus, it was viable that tea water was used to remove indoor formaldehyde.a) The effect of removing formaldehyde was impacted by the concentration of tea water obviously; the removal efficiency of formaldehyde reached to the best when the concentration of tea water was 5.0g/L;b) With different kinds of tea, the corresponding removal effect was different, but its influence was small;c) The removing formaldehyde of cooking tea water was a little better than marinating tea water;d) The same tea could be cooked continuously for recycling. The recycling number was determined by the tea, but the removal of formaldehyde was lowering more and more;e) The effect of removal formaldehyde was also related with the concentration of formaldehyde. In a certain range of formaldehyde concentration, the higher concentration of formaldehyde was, the bigger removing effect was;f) The removal of formaldehyde was more than 70%, when using tea water to remove the formaldehyde in an office room; so the effect of removing formaldehyde was very obvious.(3) Comparing the experiments of removing indoor formaldehyde by copper sulfate, silver nitrate and tea water, it was showed that all of them had very obvious removing effect, and the removal of formaldehyde by tea water was better than the others.