Study On The Performance For Adsorbing Heavy Metal Ions By Nano TiO₂ Loaded Attapulgite

Attapulgite is a kind of hydrous enrich magnesium silicate clay mineral of layered chain structure with special crystal structure and the function of adsorption and colloidal carrier.Therefore,it is widely applied in every industries of our life,such as,Petroleum,chemical industry,building materials,medicine,agriculture,environmental protection and other fields.Due to the advantage of good adsorption effect,low-cost,renewable simple in the aspect of adsorbing the heavy metal ions,it has become the research focus in the field of removing heavy metal ions in water by adsorption.The purpose of this project is to improve the capability of adsorbing heavy metal ions by Attapulgite.Modify attapulgite in different conditions,attapulgite as carrier,composite materials of attapulgite loaded nanometer TiO2 is prepared by a sol-gel,Compare composite materials with modified attapulgite Attapulgite about the capability of adsorbing heavy metal ions in solution.First,the project studies modified attapulgite in acid environment,systematic studies effects of acid concentration,stirring time,acidification temperature and other factors for attapulgite adsorb heavy metal ions.The attapulgite is modified in environment of high temperature as secondly studies,systematic studies effects of baking temperature,baking time and other factors for attapulgite adsorb heavy metal ions.While attapulgite is modified,composite materials of attapulgite loaded nanometer TiO2 is prepared by a sol-gel.It is been characterization and analysis by FT-IR,XRD,SEM and other means,and compare the capability of adsorbing heavy metal ion between composite materials and modified attapulgite by spectrophotometer.The composite materials synthesis process of attapulgite loaded nanometer TiO2:v(TBOT):v(C2H5OH)=1:5,adding 5mL triethanolamine,dropping the pH=5 solution is mixed by 20ml of absolute ethanol,5ml of deionized water and a certain amount of nitric acid in vigorous stirring in sol,adding a certain amount of attapulgite and a small amount of polyethylene glycol then high speed stirring 90min,ultrasonic dispersion 60min,removing excess sol,aging gel is prepared.120? pretreatment 2h,450? calcination 2h,obtaining a composite material A Series,650? calcination 2h,obtaining a composite material B Series.The adsorption properties of composite material of attapulgite load nanometer TiO2 is significantly higher than that of single of attapulgite modified and stability of surface particles,desorption,reuse ability,etc is higher than that of single of attapulgite modified.But the composite materials showed different adsorption capacity for different heavy metal ions.The adsorption can reach 98.65%in Ni2+ solution and 91.83%in Mn2+ solution,but it is significantly higher than that without modified attapulgite,in adsorption equilibrium state,its adsorption capacity are natural attapulgite 128.95%and 114.51%respectively.