Preparation Of Rabbit Hair Keratin Membrane And Its Adsorption Of Heavy Metal Ions

In the textile field,there is a large amount of rabbit hair wastes unsuitable for weaving produced every year,among which keratin content accounts for more than90%.Research has shown that macromolecular keratin has stronger chelating to heavy metal ions,which can be used as an adsorbent for heavy metal ions in wastewater.In order to reduce the waste of rabbit hair resources and develop its application in the field of adsorption,macromolecular keratin was extracted from wasted rabbit hair in thus paper,then prepare nanofiber membrane martial and characterized its adsorption performance.The main research contents are as follows:This topic chooses the method of reduction first and then dissolution,uses L-cysteine as a reducing agent,studies the four factors such as the concentration of L-cysteine in the solution,the p H value,the reacting temperature,and time on keratin extraction rate of wasted rabbit hair and solubility of rabbit hair in dimethyl sulfoxide solvent.The test result manifests that when the concentration of L-cysteine as 5%,p H as 10,reaction temperature as 85?and reaction time as 45 min,the extraction rate of rabbit hair keratin was 70.09%.The fitting results show that the solubility of rabbit hair keratin conforms to the multivariate linear model,and the solubility of the extracted keratin in dimethyl sulfoxide solvent is 13.06%under the optimal conditions.The keratin can be used as a matrix material to prepare nanofiber membrane,which can be used to adsorb heavy metal ions.In order to improve the mechanical properties of protein membrane,mix keratin powder and polyacrylonitrile and modify by ultrasonic and then characterize the mechanical properties,hydrophilicity,and water resistance of membrane materials with different mixed ratios.The results showed that,along with the increase of the polyacrylonitrile content,the mechanical strength of the membrane increased,but the hydrophilicity weakened.When the ratio of keratin/PAN was 60:40,the membrane had excellent physical properties and hydrophilicity,the breaking strength was 4.15pa,the breaking elongation was 12.93%,and the swelling rate was 20.08%.Therefore,the composite membrane was prepared with a mixture ratio of 60:40.Based on the single factor analysis,the best condition is jet rate as 1.0ml/h,spinning voltage as 20k V,and curing distance as 10cm.Taking Cu²⁺as an example,test for the adsorption capacity of membrane and nanofiber membrane.The adsorption capacity of the membrane was 30.18mg?g^-1,while nanofiber membrane was 37.94mg?g^-1.From the comparison,we know that the nanofiber membrane had better adsorption capacity.Membrane is easy to break when being impacted by water flow or impurity collision,so it cannot be used as adsorption material directly.In order to improve the durability of its as adsorption material,this article choose PP melt-blown nonwovens as support materials,prepare laminated composite,and test the adsorption capacity of them.The copper ions adsorption of membrane was 30.32 mg?g^-1,the nanofiber membrane was 37.91 mg?g^-1.The result shows that the membrane`s adsorption ability increases slightly,nanometer fiber membrane adsorption ability is reduced.However,the adsorption performance of the nanofiber membrane composites is still obviously better than that of the solution cast blend membrane composites in general.