Research On Removal Of Formaldehyde From Indoor Air Pollutants By Activated Carbon With Sludge Based Activated Carbon

Indoor pollution is a hallmark of air pollution,Indoor formaldehyde pollution is particularly serious.Every year,a lot of people die from formaldehyde pollution and the number of death is increased year by year.Therefore,the removal of indoor formaldehyde cannot be delayed.In this thesis,using adsorption method to remove the indoor formaldehyde is discussed.Municipal sludge is used to prepare adsorbents for the removal of indoor formaldehyde.Research shows that the sludge is a useful resource,and can improve the indoor environment and purify formaldehyde pollution.Firstly,in this paper,the process of preparation of sludge-based activated carbon was studied by chemical method,which is used municipal dewatered sludge as raw material.Through single factor experiments,the preparation conditions such as carbonization temperature,activator type and concentration,solid-liquid ratio,activation temperature and time were examined,and the effect of removing formaldehyde was studied.Finally,the sludge-based activated carbon obtained from the best preparation conditions was obtained.The removal of formaldehyde is best,with a maximum removal rate of 60.16%.At the same time,the comparison of formaldehyde removal performance between commercial activated carbon and walnut shell activated carbon shows that the sludge-based activated carbon has good physical properties and the effect of removing formaldehyde is obvious.Secondly,using sludge-based activated carbon as adsorbent carrier,using metal modification methods,the effects of active components,metal loading,and calcination temperature were examined through single-factor experiments,and the optimal removal of formaldehyde was optimized.The effect of removing formaldehyde from the obtained adsorbent is obvious.The experimental data and BET characterization showed that the physical properties of the modified adsorbent had a certain change,but the effect of removing formaldehyde was improved obviously,and the maximum removal rate was 89.47%.The infrared characterization of the adsorbent showed that the content of oxygen-containing functional groups on the surface of the modified adsorbent increased,and the adsorption of formaldehyde molecules was stronger,and the low-concentration formaldehyde pollution could bequickly and effectively removed.It also proves that sludge as a waste resource,with its preparation of adsorbent to remove formaldehyde pollution has a good application prospect,and is an important development of sludge resource technology.Finally,a single factor experiment was performed to compare the reaction conditions of formaldehyde removal.Experiments show that,except for reaction temperature and humidity,which promotes the volatilization of formaldehyde,under other reaction conditions,the effect of adsorbent on the removal of low concentration of indoor formaldehyde is obvious,and the removal efficiency is over 90%.Sludge-based activated carbon used as a sorbent to remove indoor formaldehyde still has certain limitations.However,the effect of removal of formaldehyde under suitable conditions and conditions is good.It still has high market value and can meet the goal of sludge recycling,to achieve "by waste treatment."...