Removing Low Concentrations Of Sulfur Gases With 5A Zeolites-based Adsorbents

Sulfurous gases?H2S and SO2?are the main air pollutants,which can not only destroy the environment,but also seriously harm to human health.To develop a highly efficient and low-cost solid adsorbent for removing the low concentrations of sulfur gases is an issue to be addressed.Based on the adsorption characteristics of various types of adsorbents,we used the5A zeolites and modified 5Azeolites as the supporter,the common metal oxides?ZnO,CuO and Fe₂O₃?and alkaline substance?sodium,hexamethylenetetramine and triethanolamine?as the active ingredient to prepare different types of adsorption materials.In the paper,the influences of the method of preparation,the type of the active ingredient,the active ingredient loading,calcination temperature,the reaction temperature and other conditions on the performance of a low concentration of sulfur-containing gas and the material structure were studied.The contents of the experiments are listed as follow:1.A variety of adsorption materials were prepared by.5A zeolites as the use of raw materials,loading on metal oxides and alkaline substances respectively.The optimum active components?ZnO and triethanolamine?were screened out by breakthrough tests.It was found that the use of zinc oxide as the active component of adsorption material prepared for the removal of low concentrations of H2S gas had a relatively good result,and the adsorption performance of ZnO/5A was associated with loading of zinc oxide.The adsorbent had best adsorption effect when loading capacity of zinc oxide reached 30 wt%.The adsorption performance of ZnO/5A-20 adsorbent prepared by direct precipitation was better than the methods by immersion method.2.The big specific surface area of the supporter was prepared by modifing 5A zeolites.The average porediameter of the support materials was 4.34 nm,specific surface area was 540m²/g.And different loading adsorbents were prepared by loading different zinc oxide which was the active component.The affects of zinc oxide loading,calcination temperature,reaction temperature and other factors on the low concentration of H2S adsorption performance were investigated.The results showed that when the calcination temperature at 250?,the reaction temperature at 175?and loading 30 wt%zinc oxide,the adsorption material had better adsorption properties to remove the H₂S gas,and the breakthrough times reached 110 min,and the adsorption reaction mechanism was derived by XPS.3.Adsorbents were prepared by modification of 5A zeolites loading on triethanolamine,and the effects of triethanolamine loading,reaction temperature on adsorption performance of the low concentration of SO2 were investigated.The results showed that loading triethanolamine was advantageous to the adsorption of low concentration of SO2.When loading triethanolamine was 100 wt%at 20?,adsorbent's breakthrough test time reached205 min,saturated adsorption amount was 91.41 mg/g.The adsorption reaction mechanism was derived by Fourier infrared spectrum and XPS.