Preparation Of Cu-MOF Functionalized PP/Cellulose Spunlaced Nonwovens And Study On Its Properties

Metal organic frameworks?MOFs?are porous materials composed of metal ions or clusters and organic ligands by self-assembly.In view of their high specific surface area,porosity,excellent adsorption and catalysis performance,MOFs have a promising application prospect in the field of dye wastewater treatment?WWT?.However,MOFs are usually powdery and hard to be separated from aqueous solutions after having been used in dye WWT,which limits their practical applications.To solve this problem,MOFs can be fixed on a substrate material.Spunlaced nonwoven materials are ideal substrate material due to their excellent mechanical properties and high hygroscopicity.However,conventional spunlaced nonwoven materials are functionally single,which means low added value.Thus,spunlaced nonwoven materials can be endowed the function of dye WWT by use of fixing MOF materials on their surface,which can broaden their practical application.In this paper,a novel kind of Cu-MOF material was prepared via the solvothermal method.The 4,4-bipyridine ligand was modified with 1,2-dibromoethane and then copper acetate was added as the source of metal ion.Then,the morphology and structure of Cu-MOF were characterized,and its dye removal performance were measured.The results showed that the Cu-MOF had a unique flower-like structure with large pore size.The dye removal efficiency of Cu-MOF would change for in different kinds of dyes in aqueous solution.Cu-MOF presented the higher removal ability of acidic dyes than that of the basic dyes.Cu-MOF had the excellent the removal ability for the dye aqueous solutions with different concentration.Its dye removal rates were more that 90%for the researched dye aqueous solutions within 40 minutes.After having been repeatedly used up to five cycles,the dye removal rate of Cu-MOF still kept above 80%.Then Cu-MOF was fixed on the double PP/cellulose spunlaced nonwoven material composed of cellulose fiber layer and PP fiber layer by in situ growth method.Firstly,the cellulose fiber layer surface was modified by carboxymethylation to enhance the adsorption capacity of Cu²⁺.Next,Cu-MOF was attached on the surface by solvothermal method,and Cu-MOF@PP/cellulose spunlaced composite nonwoven material was obtained.The structure and performance of the composite material were characterized,and their dye removal ability were measured.It could be concluded that Cu-MOF was successfully loaded on the surface of cellulose in formation of its unique flower-like structure.Its tensile strength and elongation at break slightly decreased.The dye removal ability of the acidic orange 7 in aqueous solution at low concentration was better.The dye removal ability of the composite nonwoven material could be affected by the changing content of hydrogen peroxide,and the hydrogen peroxide content was15?L,the dye removal ability of the composite nonwoven material was optimal.After having been repeatedly used five cycles,the dye removal rate of the composite nonwoven material was 61%,which presents the limited recyclability.On the basis of the previous researches,Fe/Cu-MOF materials were synthesized by introducing FeCl₃ to the preparation system of Cu-MOF material.Then Fe/Cu-MOF@PP/cellulose spunlaced composite nonwoven material was prepared by situ growth method.The results demonstrated that introduction of Fe³⁺changed the morphology of Cu-MOF from flower-like to rod-like.The formation of Fe and Cu bimetallic system enhanced the catalytic effect and the degradation rate of different dyes.Repeated experiments showed that the dye removal rate of Fe/Cu-MOF@PP/cellulose spunlaced composite nonwove materials was 75%after having been repeatedly used five cycles.