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Research progress in selected lysine,glutamate,glycine,methionine and zinc sulfate the preparation of single chelate of amino acid with zinc.Highly pure chelate of amino acid with zinc were separated using precipitation fractionation by added organic solvent.Discussion the molar ratio,pH,solution,reaction temperature and time on the prep-aration. Extractant type,the ratio of extractant and chelate solution,solvent for separation and mensuration.AAS mensuration the chelation rate determined the optimum conditions. Dithizone and UV spectrum identified the nature.The mensuration and preparation metho-ds used for other singe chelate of amino acid with trace elements and zinc-amino acid compound chelates,determined the rebality and scope.Finally,the mensuration methods used for commercial amino acid trace fertilizer products,reference for this kind of produc-ts.The main results were as followed:1. The optimum preparation conditions for single chelate of amino acid with zinc synthesized were as followed:(1) Lys-Zn:molar ratio(amino acid:metal ions) 2:1,pH 6.5-7.5,solution deionized water,reaction temperature 60℃,reaction time 1h. (2) Glu-Zn: molar ratio 2:l,pH 5.5-7.5,solution deionized water,reaction temperature 90℃,reaction time 0.5 h. (3) Gly-Zn:molar ratio 2:l,pH 6.5,solution 1‰sulfurcacid, reaction temperat-ure 90℃,reaction time 0.5 h. (4) Met-Zn:molar ratio 2:1,pH 4.5-5.5,solution 1% sulfurca-id, reaction temperature 80℃,reaction time 1 h.2.The optimum separation and mensuration conditions for single chelate of amino acid with zinc synthesized were as followed:(1) Lys-Zn:Mathanol as extractant, the ratio of extractant and chelate solution between 10:1-15:1,solvent were 5‰sulphuric acid. (2) Glu-Zn:Mathanol or ethanol as extarctant, the ratio of extractant and chelate solution between 10:1-15:1,solvent were 20% sulphuric acid. (3) Gly-Zn:Ethanol as extarctant,the ratio of extractant and chelate solution between 10:1-15:1,solvent were 5%o sulphuric acid. (4) Met-Zn:Mathanol as extarctant,the ratio of extractant and chelate solution between 10:1-15:1,solvent were 1% sulphuric acid.The chelation rate were as followed:Lys-Zn 69.09%,Glu-Zn 82.60%,Gly-Zn 86.61% and Met-Zn 80.53%.3.Dithizone and UV spectrum complementary identifying the single chelate of amino acid with zinc.The result showed that the color of Lys-Zn was purple and others were blue-violet,it was consistent with chelation rate.After separated,the color of amino acid chelates solution were blue-green,showed that free Zn2+ complete separated by organic solvent.The UV spectrum of amino acids,peaks of amino acid chelates changed,proved the reaction of chelation take place.4.The method used to synthesize and determine other single chelate of amino acid with trace elements.The qualitative test result showed:The color of dithizone for chelate of amino acid with copper and ferrous were deviation,because of the color of metal ions, but UV spectrum could make up this deviation.The color of separation showed the separated conditions for chelated of amino acid with zinc could use to other amino acid chelates.The chelation rate of amino acid chelates were as followed:(1) Chelate of lysine with copper,manganese,ferrous were:54.26%,64.02%,61.15%. (2) Chelate of glutamate with copper,manganese,ferrous were:84.96%,80.28%,87.10%. (3) Chelate of glycine with copper,manganese,ferrous were:72.18%,82.73%,91.63%. (4) Chelate of methinoine with copper,manganese,ferrous were:89.54%,60.89%,40.76%.Amino acid chelates could chan-ge synthesize condition to improve chelation rate.5.The method would be used to synthesize and determine compound of amino acid with zinc.The qualitative test showed the reaction of chelation take place,but different mixed proportion had different complexes.Mean time color of dithizone showed free zinc ions complete separated.The chelation rate were between 69%-81%.6.Mensuration for amino acid chelated trace fertilizer.Dithizone identifying the nature.The color of the solution showed that little free metal ions in products.The test studied extractant volume and time,the optimum conditions were evaluted based on the chelation rate as followed:40 ml methanol added to 1g sample,extracted 30 min.The chel-ation rate of amino acid chelated ferrous,manganese were greater than 90%,amino acid chelated zinc,copper were greater than 50%.
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