The Construction And Application Of Supramolecular Gel Based On Amino Acid Derivatives

Heavy metal pollution has attracted much attention due to its harmfulness to human and enverimonent.Therefore,the controlling sewage of heavy metal pollution has become an urgent problem.Supramolecular materials possess three-dimensional network structure,which makes it easy to capture heavy metal ions.What’s more,they can be recycled and utilized.Moreover they are inexpensive and readily available.therefore it shows a good prospect in treatment of wastewater which contains heavy metals.Amino acids are the basic building blocks of the proteins necessary for the living system,they are non-toxic and harmless.They are also good units for constructing supramoleculars.In this paper,we designed and synthesized a series of amino acid derivatives,and constructed supramolecular gel by using the derivatives.Such supramolecular gel has been applied to wastewater treatment containing Pb²⁺.The main contents are showed as follows:1.The construction of amino acid derivative supramolecular gel and the application in the adsorption of Pb²⁺.Amino acid derivatives were prepared by condensation of L-valine,L-aspartic acid,L-tryptophan with 3,4,9,10-perylene tetracediamide（PTCDA）.The self-assembled supramolecular gels,including VP（L-valine derivative gel）,AP（L-aspartic acid derivative gel）,TP（L-tryptophan derivative gel）,were formed from the amino acid derivatives by ultrasound.Infrared spectroscopy（ATR-FTIR）,X-ray diffraction（XRD）and rheological instrument were used to explore the properties of the materials.In addition,the microstructures of the materials were characterized by scanning electron microscopy（SEM）.By studing the adsorption of VP,AP and TP on Pb²⁺,we found VP has best properties.In order to study the adsorption performance of VP gel on Pb²⁺,we investigated the effects of different adsorbent content,pH,time and concentration on the adsorption of Pb²⁺.We also investigated the maximum adsorption rate and amount of Pb²⁺.The adsorption kinetic model and isotherm will be deter mined.Characteristics of competitive adsorption of Pb²⁺by VP gel were be studied.What’s more,the sorption/desorotion behavior of VP gel were researched by multiple cycles experiment.Finally,the adsorption mechanism of VP gel on Pb²⁺will be studied by SEM and EDS.2.Construction of graphene oxide doped with valine derivatives supramolecular gel and application in Pb²⁺adsorption.The adsorption performance of VP on Pb²⁺will be improved by adding GO to gel.The VP/GO(THF/EtOH/H₂O（V=3:3:4）gel will be prepared by ultrasound in the same way.The self-assembly driving force of the gel were be studied by infrared spectroscopy,ultraviolet spectroscopy and fluorescence emission spectroscopy.The effects of different adsorbent content,pH,time and concentration on the adsorption of Pb²⁺were be investigated.In addition,VP/GO xerogel was added to the mixed solution of Cu²⁺,Hg²⁺,Ni²⁺,Mn²⁺,CO²⁺and Pb²⁺under the same conditions to study the competitive adsorption by VP gel.What’s more,the sorption/desorotion behavior of VP gel were researched by multiple cycles experiment.Finally,the morphology,elemental changes and adsorption mechanism of VP/GO adsorbed Pb²⁺will be studied by SEM and EDS.