Preparation Of Nitro-organic Compounds Modified Organic-inorganic Hybrid Silica Materials For The Adsorption Of Rhenium (?)

In this study,organic-inorganic hybrid silica was used as basis material to prerare three types adsorbents containg nitro-organic compounds.The adsorbents were characterized by XRD,N2 adsorption-desorption,TEM,SEM,then the adsorption behaviors of the adsorbents towards rhenium were detailedly studied.We prepared amino-functionalized organic-inorganic hybrid silica materials by one-pot,and then modified with salicylaldehyde by the reaction of aldehyde group and amino.The chlorine atoms and epoxy ring in epichlorohydrin reacted with hydroxy and amino respectively to obtain the adsorbent.XRD,N2 adsorption-desorption,TEM,SEM proved that the existence of APTES will destroys the ordered mesoporous structure.The maximum adsorption quantity is about 221.37 mg·g-1 at pH 3,and the adsorption behavior obeys the Langmuir model.The experiments proved that mixed ions(Cu2+,Zn2+ and Mn2+)could almost separate with Re(VII)onto the adsorbent at pH 1~1.5.The adsorbent has satisfactory cycle performance.In the end,ReO4-was adsorbed on the proton tertiary amine groups of adsorbent via electrostatic attraction by infrared spectroscopy and X-ray photoelectron spectroscopy analysis.We got a new adsorbent by crosslinking amino on the organic-inorganic hybrid silica materials with the help of glutaraldehyde.Infrared spectroscopy proved that the primary amine on the adsorbent has been turned into schiff base.With the help of C=N,the adsorption capacity improved significantly compared with base material.The selective experiment demonstrated that the adsorbent can separate Re(VII)from Cu2+,Zn2+,Mn2+ completely.The application performance indicated the adsorbent have excellent selectivity and cycle performance,the maximum adsorption quantity is about 270.13 mg·g-1 at pH 4,so it have a good application prospect.We choose SBA-15 as substrates and prepared an series of adsorbent with C=N.In order to study the influence of crosslinking agent on the adsorption capacity,we replace glutaraldehyde with epichlorohydrin and prepared an series of adsorbent with double secondary amine groups.XRD,N2 adsorption-desorption,TEM,SEM could prove that each adsorbent keeps the ordered mesoporous structure.Infrared spectroscopy demonstrated that primary amine modified on the SBA-15 successfully with the help of glutaraldehyde and epichlorohydrin.The acidity test and the maximum adsorption results showed that adsorbents with C=N have better adsorption capacity but adsorbents with double secondary amine groups suit for broader range of acidity condition.The structure of the modification agent have an effect on adsorption capacity,the maximum adsorption quantity is about 198.77 mg·g-1.The adsorbent showed great selectivity and circularity.