| The studies that relate to the anime-collectors of Al-Silicate minerals involve in the following : character of the main gangues of bauxite and design for the collectors, synthesizing, the flotation property , the adsorption mechanism and the structure-activity relationship of the collectors.Firstly, the kaolinite , pyrophyllite and illite comprise (Si, O) tetrahedron and (Al, O) octahedron. When minerals , it's (001) cleavages completely and forms bedding plane of crystal , which carries aptotic electronegative , but it's (110) and (010) cleavage incompletely and form end faces of crystal , which carries alterable electric charge that alter with pH . By counting breaked bond , the floatability is pyrophyllite >kaolinite>illite .So it is the point of exertion to catch kaolinite . From the basic structure model of collector and characteristic of Al-Silicate minerals , the collectors of Al-Silicate minerals are designed , the polar groups of which are -NHCH2CH2CH2NH2 , -0-CH2CH2CH2 Mi and -N (CEO 2 , and the no- polar groups of which are n-C12H25- n-C14H29,n-C16H33-,n-C18H37- .Secondly, the N- alkyl-l,3- diaminopropanes and the aether-alkyl-propyl- amines are made by the following reactions :RNH2+H2C=CH-CN→RNH2 CH2 CH2CN RNHCH2 CH2CN Na+c^OH RNH CH2 CH2 CH2 NH2 R= n-C12H25-, n-CnH29- n-C16H33; n-C18H37- .and the aether-alkyl-propyl- amines are made by the following reactions :ROH+H2C=CH-CN→RO CH2 CH2CN ROCH2 CH2CN WRO CH2 CH2 CH2 NH2R= n-C12H25- n- CMH29- n-C16H33 n-C18H37. and the N,N- dimethyl-alkyl-amines are made by the following reactions :RNH2+2HCHO HCOOH RN(CH3)2+CO2R= n-Ci2H25-, n-CHH29- .Thirdly, three pure minerals, the kaolinite , pyrophyllite and illite, are adopted for investigating the flotation properties of the synthesized reagents. TheVI__________________________________________________________________________________abstractresults of the flotation indicate that: Catching the aluminum silicate minerals, the synthesized reagents are better than the DDA. To diamines, the order of catching aluminum silicate minerals is the pyrophyllite >the kaolinite >the illite. The longer of carbon chain of the DNs, the smaller caching ability to aluminum silicate minerals. To aether-amines and to tertiary amines, the order of catching aluminum silicate minerals is the pyrophyllite >the kaolinite >the illite, and the longer of carbon chain of them, the stronger catching ability to aluminum silicate minerals. The order of catching aluminum silicate minerals is the DNs >the DRNs >the ONs. The DNi2 is the best of the synthesized reagents, which has strong caching ability to the kaolinite and pyrophyllite in wide pH (4--10).The catching mechanism of the synthesized reagents was confirmed by the measurements of zeta potential, IR spectrum and solution chemistry of aluminum silicate minerals. The synthesized reagents can adsorb on the mineral surface and change the zeta potential of aluminum silicate minerals .The IR spectrums approve that the action is electrostatic adsorption mainly and go with hydrogen bond in part. It is explained the floatation action that the synthesized reagents catch the aluminum silicate minerals by combing solution chemistry of aluminum silicate minerals and the surface electrical property.The structure-activity relationships of the collectors of the aluminum silicate minerals are discussed by the calculation of radical electro-negativity, radical size, reagent specific exponent, hydrophilic lipophilic balance, partition ratio, quantum chemistry parameters of molecule and cation , and solution chemistry of the synthesized reagents. The conclusions are following: with the no-polar groups on N of reagents increasing, the radical electro-negativity and the solid -philic energy of the reagents increase, but foamability and dissolubility of the reagents decrease, with the polar groups on N of reagents increasing, the adsorbing active points, foamability , dissolubility and radical size of the reagents increase. The selectivity and catching ability of the...
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