Study On Purification And Formaldehyde Adsorption Properies Of Low Grade Diatomite

The market began to use the indoor harmful gases diatomite adsorption to purify the air.However,use of a higher level of diatomaceous earth diatom content,a large number of low-end diatomite no exploitation of the paper studies the effects of different purification process for purifying effects diatomite Inner Mongolia,to determine the final diatomite purification process,and generally the adsorption properties of diatomite.The mixture ratio of the diatomite composite plate is optimized by the orthogonal test.This paper studies the effects of different purification process for purifying effect of Inner Mongolia diatomite,diatomaceous earth in order to determine the final purification process,and generally the adsorption properties of diatomite.Purification of this article were taken to diatomite mesh grading,roasting,pickling.By scanning electron microscopy morphology diatomite various changes were observed after the purification process;and the use of EDS analysis of compositional changes under study various purification processes diatomaceous earth,to determine the best combination of both diatomite purification process,and the effect of purification on the pore structure of diatomite was also studied.Diatomite adsorption experiments and research temperature influence formaldehyde adsorption properties of diatomite formaldehyde gas.The L₉?3⁴?orthogonal design method was used to design 9 mixture ratio plans.Through analyzing the mechanical properties,moisture swelling,shrinkage and viscosity of the diatomite composite plate,and combining production practice,we determined the best mix proportion plan.The adsorption of formaldehyde on the calcium silicate board was studied.The results show that diatomite content greater than 230 mesh can be used as raw material for further purification of the study;diatomaceous earth impurities in high-temperature roasting makes cracking volatile,and increases with the increase of calcination temperature roasting time,Si content gradually increased,its best roasting process at a temperature calcination at 600?3h;With the increase of the concentration of sulfuric acid,the corresponding increase in the Si content.However,the concentration of sulphuric acid used in acid pickling should not be too large.Best pickling process for the mass fraction of 55%sulfuric acid,and the specific surface area of diatomite increased by 29.7%after purification.After roasting and pickling treatment,the void fraction with larger pore size in diatomite was increased,and the number of micropores in the range of9-10 nm was significantly increased.Adsorption results show that diatomite adsorption of formaldehyde gas in line with physical adsorption,acid purified diatomite best performance.The optimum mixture ratio of diatomite composite plate is as follows:the content of diatomite is 20%,the content of lime is 22.5%,the content of quartz is 30%,and the content of cement is 17.5%.The adsorption capacity of diatomite calcium silicate board and calcium silicate board without adding diatomite increased by 37.9%.