A Research For Application Of Iron Silicate Humidity Controlling Material By Steel Pickling Waste Liquor

The still pickling waste liquor contains large amounts of ferrous ions,which direct emission will cause environmental pollution and waste resources.Pickling waste liquor as raw material,We can get iron silicate humidity controlling material by reacting with sodium silicate,Not only we can deals with the pickling waste liquor,but also we can recycle the iron ions.Humidity controlling materials of Iron silicate in this research was prepared with sodium silicate and steel pickling waste liquor by chemical precipitation method.Impacts of preparative conditions,which include pH,preoxidation and aging action,The humidity controlling properties of iron silicate was investigated and the best preparing conditions were confirmed.Based on materials performance for controlling humidity and materials characterization tested by FI-IR,XRD,SEM and BET method,the author discussed humidity controlling theory of iron silicate and influencing factors on the materials humidity controlling properties.The results showed that pH had a great influence on the iron recovery rate,but had no effect on the humidity controlling properties of the prepared materials,When the pH equal to 7.5,The iron recovery rate can reach more than 99%,The effective recovery of iron ions was basically realized.Under conditions of low humidity,the suspension obtained by reacted the pickling waste liquor with sodium silicate solution after 15 h aging action.The humidity controlling material have best moisture of absorption and liberation properties.In high humidity environment,the suspension obtained by reacted the pickling waste liquor which have been oxidized with sodium silicate solution after 15 h aging action,The prepared humidity controlling material have best moisture of absorption and liberation properties,Iron silicate humidity controlling materials have amorphous structure,whose specific surface area are more than 318 m~2/g,pore volume are about 0.34cm~3/g,and pore diameter are about3.8nm,The structure with reletively larger surface area and pore volume,but smalleraverage pore size,This structure is beneficial to the diffusion of water vapor on the surface and interior of the material,which have a larger moisture absorption capacity and a faster moisture liberation speed.