Study On Preparation Of Compound Amino Acids By Green Hydrolysis Of Feather

With the rapid development of global stockbreeding industry, feathers have been rated as number one in all the waste generated by large scale poultry farming. Feather is rich in keratin, which contains a variety of amino acids, trace elements, vitamins and some unknown growth factors. However, most feather has been abandoned, resulting in resources waste and environmental pollution. If these abandoned feather protein can be recycled, not only environmental pollution can be reduced, but also recycling economy could be realized, meanwhile, great economic benefits and social benefits can be obtained. So it is of profound significance to research and develop keratin, amino acids and its related products, and make rational use of them.Chicken feather from the Chongqing vegetables market was investigated with microwave as a rapid heating way and the ionic liquids as catalyst. Factors associated with hydrolysis performance, such as mass to volume ratio of solid to liquid, concentration of HCl, microwave power and microwave irradiation time were investigated. Results showed that microwave-assisted ionic liquids could accelerate the hydrolysis compared with conventional heating or microwave irradiation heating. The yield of compound amino acids was up to 82.10% under conditions following mass to volume ratio 1:9, concentration of HCl 6.0 mol·L-1, microwave power 800 W, and the optimum catalyst of [BMIm]Cl 1.5g for 30 min. The presented process is economically feasible for rapid and efficient reaction, higher yield, lower pollution and so on. At the same time, hydrolyzate obtained under the optimum conditions was used to prepare Cu(Ⅱ)-amino acid compound chelate. Effects of material ratio, pH value, microwave power and reaction temperature on chelate reaction were investigated. Results indicated that chelate rate (ratio) of compound amino acids was up to 92.55% with copper sulfate as optimum chelating agent under optimum conditions following agent feed ratio 1:2, pH value 6, microwave power 600 W, and microwave irradiation for 40min at 60℃. Trace element in the amino acid chelate plays an important role in animal nutrition as feed additive, so its rational use could make the absorption of trace element for animal and protect ecological environment.The changes of material before and after hydrolysis were analyzed by infrared spectroscopy, automatic amino acid analyzer, differential thermal analyzer (DTA) and differential thermal analyzer (TGA). Based on experimental data and the theoretical analysis, the keratin hydrolysis mechanism was discussed and a simple theoretical model was established to describe keratin hydrolysis behavior under the microwave-assisted ionic liquid system.In order to achieve maximum use of resources and the purpose of green hydrolysis, activated carbon was prepared from solid waste produced in the process of hydrolysis. It revealed that adsorption value of methylene blue and iodine researched 9.2 mL/0.1g and 83.0 mL/0.1g, respectively, under the conditions following agent feed ratio 1?1, H3PO4 of 50%, conventional dipping for 24 h, microwave power 800 W, and microwave irradiation for 15 min. Feather activated carbon prepared by microwave radiation has a certain adsorption capacity, so it is an inexpensive raw material for preparation of activated carbon. However, the activated carbon adsorption value is expected to be further enhanced.