Study On Adsorption And Degradation Of Anionic Dyes By Silane Modified Titanium Pillared Montmorillonite

Montmorillonite was widely used for the removal of pollutants in water,since its inexpensive,easily available,environment-friendly and other excellent properties.However,the cation exchange capacity and interlayer spacing of montmorillonite are small,and the adsorption capacity of montmorillonite is limited.On the other hand,the surface has hydrophilicity and the adsorption capacity of hydrophobic organic pollutants is weak.In order to overcome the above shortcomings,usually modified montmorillonite,inorganic pillar can increase the specific surface area and interlayer,organosilane modification can enhance the pro-organic.While the two methods of compound modification to remove water pollutants is relatively small,and the exploration of the conditions of improvement is not sufficient.In this study,hydroxy-titanium cations were introduced into the interlayer of montmorillonite by ion exchange and titanium pillared montmorillonite was obtained after calcination.And then different silane-modification was conducted in the solvents with different polarities,such as cyclohexane,anhydrous ethanol,and methanol.Finally,the structures,properties and formation mechanisms of the products were investigated by XRD,ATR,TG-DTG,SEM,specific surface area and pore volume analyser.And appropriate products were adopted for studying the adsorption of Orange II which is an anion dye of these processes.This research is conducive to the application of montmorillonite for the removal of environmental pollutants and the synthesis of clay mineral-polymer nanocomposites.The main results of this paper are as follows:(1)The polarity of the reaction solvent has great influence on the grafting of different ionic silane molecules.For the 3-aminopropyltriethoxysilane(cationic)modified titanium pillared montmorillonite samples,the silane grafts Ti-Mt-M-A(4.59 %)>Ti-Mt-E-A(4.12 %)>Ti-Mt-C-A(1.72 %),the alcohol system is more favorable for the silane loading;For ?-mercaptopropyltriethoxysilane(anionic)modified titanium pillared montmorillonite samples,the silane grafts were Ti-Mt-C-M(3.75 %)>Ti-Mt-E-M(2.7 %)>Ti-Mt-Mt-M(2.22 %);For the trimethylethoxysilane(nonionic)modified titanium pillared montmorillonite samples,the silane grafts were Ti-Mt-E-T(2.4 %)>Ti-Mt-Mt-T(1.58 %)>Ti-Mt-C-T(1.38 %).(2)For different amounts of ethoxylated silane modified titanium pillared montmorillonite,the less the amount of ethane groups was higher,the silane grafts were Ti-Mt-M-T(2.45%)>Ti-Mt-E-D(2.33%)>Ti-Mt-E-S(2.25%)>Ti-Mt-E-E(1.89%),For Ti-pillared montmorillonite with different electrical silane types,the silane grafts were Ti-Mt-E-A(4.12 %)> Ti-Mt-E-M(2.7 %)>Ti-Mt-E-E(1.89 %).The electrostatic interaction between the charged group and the positively charged titanium ion and the negatively charged lamellae is stronger than that of the non-ionic silane,and the grafting amount of the ionic silane is also higher than the same conditions of non-ionic silane.(3)Titanium pillared montmorillonite for organosilane modification can improve the adsorption capacity of anionic orange ?.The removal rate of Ti-Mt-E-A was 96.7%.Ti-Mt-E-E,Ti-Mt-E-E,Ti-Mt-E-E,Ti-Mt-E-E,and Ti-Mt-E-E were mixed with Langmuir adsorption model.