The Preparation And Application Of The Straw Based Hydrogel-nanometal Compsites

In this work,the wheat straw cellulose was used to prepare wheat straw cellulose graft copolymerization hydrogel and ionic liquid regenerated wheat straw cellulose/chicken feather protein hydrogel.The hydrogels were applied as a nanometal template and a reactor for the catalytic reactor.The main research contents and conclusion are as following:1.The acrylic acid?AA?was a monomer was grated on to the wheat straw cellulose?WSC?in the presence of the initiator and crosslinker,then generated polymer and polyvinyl alcohol?PVA?had a semi-interpenetrating effect and the wheat straw cellulose hydrogel?WSC-g-PAA/PVA?was perpared.WSC-g-PAA/PVA hydrogel was a template to load metal ions and prepare hydrogel-M composites.Fourier transform infrared spectroscopy?FTIR?,The gravimetric analysis?TGA?,thermal scanning electron microscopy?SEM?,energy dispersion spectrum?EDS?analysis and diffraction analysis?XRD?were employed to characterize the hydrogel-M composites.FTIR,SEM and EDS analysis showed that the adsorption effect of hydrogel on Cu???and Ni???was significant and the adsorption ofnanometal ions was distributed evenly on the surface of hydrogel and prevented the accumulation.The result proved that the adsorption capacity were 177.0 mg copper and 156.1 mg nickel,respectively.TGA and XRD analysis showed that the stability of the hydrogel-M composites was better than that of the hydrogels,and the three-dimensional network structure of hydrogels also prevented the oxidation of nano-metal.2.The hydrolysis of NaBH₄ was catalyzed by WSC-g-PAA/PVA-Cu?Ni?and the effects of several parameters such as the amont of catalyst,the initial concentration of NaBH₄ and the reaction temperature were studied.The result indicated that the activation energy were 32.66 kJ mol-1 and 34.83 kJ mol-1 for WSC-g-PAA/PVA-Ni and WSC-g-PAA/PVA-Cu,respectively.The increasing of the catalyst amounts and initial concentration of NaBH₄ improved the rate of generation hydrogen.At the end of the fifth usage and after storage of 30 days,the two catalysts were always remained a high activity.3.The degradation of 4-NP and CAP were catalyzed by WSC-g-PAA/PVA-Cu and the effects of several parameters such as the amount of catalyst,the amount of NaBH₄ and the reaction temperature were studied.According to the Box-Behnken design,the optimal values of the operation parameters under the related constraint conditions were obtained at 30 ?,0.07 g catalyst,0.07 g NaBH₄ for WSC-g-PAA/PVA-Cu with degradation of 4-NP and at 20 ?,0.03 g catalyst,0.03 g NaBH₄ for WSC-g-PAA/PVA-Cu with degradation of CAP.The degradation rate of 4-NP and CAP was 99%and 90.49%,respectively.According to the thermodynamic analysis,it was found that the activation energy was 17.30 kJ mol-1 and 21.42 kJ mol-1 for degradation of 4-NP and degradation of CAP,respectively.The result indicated that the catalyst has a significant catalytic efficiency in the catalytic degradation of 4-NP and CAP.4.The WSC/CFP hydrogel was prepared by ionic liquid dissolution of wheat straw cellulose and chicken feather protein?CFP?.The WSC/CFP hydrogel and m-WSC/CFP hydrogel were an ideal template to prepare WSC/CFP-Cu composites and m-WSC/CFP-Cu composites.FTIR,TGA,SEM with EDS and XRD were employed to characterize the WSC/CFP-Cu and m-WSC/CFP-Cu composites.The result indicated that the hydrogel-can effectively adsorb Cu???ions and the adsorption capacity was 30.83 mg/g for WSC/CFP hydrogel and 34.50 mg/g for m-WSC/CFP hydrogel,respectively.The FTIR,SEM and EDS analysis indicated that the nanometal was.distributed evenly on the surface of hydrogel.The adsorption mechanism of Cu???ions onto the hydrogel mainly depended on the complexation reaction between O-containing functional groups or N-containing functional groups?-NH2,-OH?and Cu???ions.The TGA and XRD analysis showed that the existence of metal nanoparticles within hydrogel has a higher thermal stability than the bare hydrogel and the loaded nanometal was stable and difficult oxidation.5.The degradation of 2-NA was catalyzed by WSC/CFP-Cu and m-WSC/CFP-Cu.And the effects of several parameters such as the amount of catalyst,the initial concentration of 2-NA and the reaction temperature were studied.The result indicated that the degradation rate of 2-NA was increased with the increasing of the amount of catalyst and reaction temperature.When the increasing of the initial concentration of 2-NA,the degradation rate was first increased and then reduced.It was found that the activation energy was 46.0 kJ mol-1 by the analysis of thermodynamics of the degradation reaction and the result indicated that the catalyst had a significant advantage in the degradation of 2-NA.