Study On Modification Of Activated Carbon And Its Adsorption Properties Of Formaldehyde

Formaldehyde is one kind of the main pollutants in indoor air. Formaldehyde is toxic. High concentration formaldehyde can do harm to people'health seriously. In recent years, the removal of formaldehyde and other indoor gases become into the hot point.The adsorption of formaldehyde onto the different adsorbents in a fixed bed reactor h as been investigated in this study .The adsorptions of formaldehyde on activated carbon absorbents have been studied, and the dependent factors of formaldehyde adsorption on activated carbon have been investigated. The main experimental results and conclusions are summarized as follows:By comparison of the adsorption capacity of activated carbon,γ-Al₂O₃ and zeolite, it has been found that activated carbon has the higher adsorption capacity than others. The experiment results indicate that larger surface area was propitious to adsorption. So activated carbon was used as the adsorbent for the further study. By comparison of the adsorption capacity of activated carbon for four different modification.The experiment results indicate that the modified activated carbon has better adsorption capacity than activated carbon that has no modified .The activated carbon modified by 0.5mol/LNaOH has the best adsorption capacity, it can achieve 7.543mg/gAC,it is 3.67 times as the activated carbon that has no modified. The samples were made by the TPD experiment, the modified activated carbon peak area has increased and the temperature of formaldehyde desorption mainly concentrated in about 270℃.The adsorption capacity of formaldehyde is main determined by pore and surface area.In addition, the regenerations of activated carbon by formaldehyde adsorption were conducted in the fixed bed adsorption reactor. The experiment results indicate that the samples have better regeneration capability and be able to use many times.