The effect of hydroxamic acid starch (HAS) and hydroxamic acid polyacrylamide (HPAM) on the flotation of diaspore and kaolinite was investigated by flotation test. It is found that HAS depresses diaspore but activates...The effect of hydroxamic acid starch (HAS) and hydroxamic acid polyacrylamide (HPAM) on the flotation of diaspore and kaolinite was investigated by flotation test. It is found that HAS depresses diaspore but activates kaolinite in acidic pulp,while HPAM activates both diaspore and kaolinite in the pH range of 2.010.5. The measurement of zeta potential shows that both HAS and HPAM can increase zeta potential of negatively charged diaspore, which indicates the existence of chemical bonding or hydrogen bonding between the reagents and diaspore. By covering the collector dodecyl amine(DDA) on diaspore surface,HAS increases the hydrophilicity of minerals and depresses the flotation of diaspore,however HPAM activates the flotation of diaspore by increasing the adsorption of DDA on diaspore surface.展开更多
N, N-diethyl dodecyl amine（DEN12） was synthesized from dodecyl amine, formic acid and acetic aldehyde. The collecting property of DENI2 on diaspore, kaolinite and illite was investigated by flotation test and infrar...N, N-diethyl dodecyl amine（DEN12） was synthesized from dodecyl amine, formic acid and acetic aldehyde. The collecting property of DENI2 on diaspore, kaolinite and illite was investigated by flotation test and infrared spectrum. The results show that in the presence of 2.0× 10^-4 mol/L DEN12, the recoveries of kaolinite and illite are all higher than 78% and the recovery of diaspore is 50% in the pH range of 5.5-6.0. The mass ratio of A1203 to SiO2 in concentrate obtained from separation artificial mixture is higher than 10, suggesting that DEN12 can be used as a collector to separate the aluminosilicates from diaspore in bauxite ores at the pulp pH below 8. The measurements of the infrared spectrum approve that the action between aluminosilicates and tertiary amine collector is strong electrostatic adsorption and that of diaspore is weak electrostatic adsorption.展开更多
The flotation of pure and natural carbonaceous iron ore samples in the oleate flotation system was investigated.Starch can depress hematite effectively in a wide pH range,but cannot depress siderite efficiently in neu...The flotation of pure and natural carbonaceous iron ore samples in the oleate flotation system was investigated.Starch can depress hematite effectively in a wide pH range,but cannot depress siderite efficiently in neutral conditions.The flotation recovery of pure hematite,siderite,and quartz in the oleate-starch-CaCl2 system is significantly different when the slurry pH varies from 4 to 12.A novel two-step flotation process was developed for the separation of iron concentrate from Donganshan carbonaceous iron ore through which the siderite concentrate is first recovered and the high quality hematite concentrates with relative high iron recovery can be obtained in the second step flotation.The siderite concentrate may be utilized directly or undergo further concentration steps to increase iron grade.展开更多
The technological mineralogy of the potash feldspar was investigated and a new collector named Yb105 was adopted to remove iron from potash feldspar ores.The technological mineralogy results indicate that the main com...The technological mineralogy of the potash feldspar was investigated and a new collector named Yb105 was adopted to remove iron from potash feldspar ores.The technological mineralogy results indicate that the main components of the ore were feldspar,sericite,quartz and kaolinite,and iron mainly existed in limonite and hematite,most of which can be removed by beneficiation.The results show the benzohydroxamic acid can not only increase the recovery of iron and reduce the consumption of oleic acid collector,but also enhance the collecting performance of oleic acid at low temperature,which can realize the flotation of the ores at a low temperature and play an important role in saving energy to some extent.Compared with oleic oil,the benzohydroxamic acid had a great advantage in removing iron from potash feldspar,a potash feldspar concentrate with Fe grade of 0.23%,K2O grade of 12.59%and Na2O grade of 0.26%was obtained by flotation with Yb105 as collector,and the yield of the concentrate was 82.55%.展开更多
The chemical nature of the interaction of starch and dodecylamine （DDA）, which generally act as depressant and collector, respectively, in the reverse flotation of bauxite, was investigated using starch-iodine tests...The chemical nature of the interaction of starch and dodecylamine （DDA）, which generally act as depressant and collector, respectively, in the reverse flotation of bauxite, was investigated using starch-iodine tests. The results obtained from the blue-value measurements for starch＋DDA＋iodine system indicate the formation of the inclusion complex for amylose-DDA system at low DDA concentration （〈2 retool/L）. However, it is less likely for amylopectin-DDA system with short helix. UV-Vis spectra of starch-iodine complexes show that each helix of amylose can accommodate two DDA molecules locating separately at its two ends, and in the helical cavity there is room available for the upcoming iodine. When concentrated DDA is tested, amylose-DDA system exhibits no characteristic starch-iodine color, owing to the presence of a compact coating of DDA molecules on starch via hydroxyl/amine hydrogen bonding. ^1H NMR spectroscopy and surface tension determination help to clarify the interaction mechanism of amylose with DDA.展开更多
文摘The effect of hydroxamic acid starch (HAS) and hydroxamic acid polyacrylamide (HPAM) on the flotation of diaspore and kaolinite was investigated by flotation test. It is found that HAS depresses diaspore but activates kaolinite in acidic pulp,while HPAM activates both diaspore and kaolinite in the pH range of 2.010.5. The measurement of zeta potential shows that both HAS and HPAM can increase zeta potential of negatively charged diaspore, which indicates the existence of chemical bonding or hydrogen bonding between the reagents and diaspore. By covering the collector dodecyl amine(DDA) on diaspore surface,HAS increases the hydrophilicity of minerals and depresses the flotation of diaspore,however HPAM activates the flotation of diaspore by increasing the adsorption of DDA on diaspore surface.
基金Project(2005CB623701) supported by the Major State Basic Research Development Program of China
文摘N, N-diethyl dodecyl amine（DEN12） was synthesized from dodecyl amine, formic acid and acetic aldehyde. The collecting property of DENI2 on diaspore, kaolinite and illite was investigated by flotation test and infrared spectrum. The results show that in the presence of 2.0× 10^-4 mol/L DEN12, the recoveries of kaolinite and illite are all higher than 78% and the recovery of diaspore is 50% in the pH range of 5.5-6.0. The mass ratio of A1203 to SiO2 in concentrate obtained from separation artificial mixture is higher than 10, suggesting that DEN12 can be used as a collector to separate the aluminosilicates from diaspore in bauxite ores at the pulp pH below 8. The measurements of the infrared spectrum approve that the action between aluminosilicates and tertiary amine collector is strong electrostatic adsorption and that of diaspore is weak electrostatic adsorption.
基金Project(2006DFB72570) supported by the Grand Project of International Cooperation of Ministry of Science and Technology of China
文摘The flotation of pure and natural carbonaceous iron ore samples in the oleate flotation system was investigated.Starch can depress hematite effectively in a wide pH range,but cannot depress siderite efficiently in neutral conditions.The flotation recovery of pure hematite,siderite,and quartz in the oleate-starch-CaCl2 system is significantly different when the slurry pH varies from 4 to 12.A novel two-step flotation process was developed for the separation of iron concentrate from Donganshan carbonaceous iron ore through which the siderite concentrate is first recovered and the high quality hematite concentrates with relative high iron recovery can be obtained in the second step flotation.The siderite concentrate may be utilized directly or undergo further concentration steps to increase iron grade.
基金Project(21776320)supported by the National Natural Science Foundation of ChinaProject(2016TP1007)supported by the Hunan Provincial Science and Technology Plan Project,China
文摘The technological mineralogy of the potash feldspar was investigated and a new collector named Yb105 was adopted to remove iron from potash feldspar ores.The technological mineralogy results indicate that the main components of the ore were feldspar,sericite,quartz and kaolinite,and iron mainly existed in limonite and hematite,most of which can be removed by beneficiation.The results show the benzohydroxamic acid can not only increase the recovery of iron and reduce the consumption of oleic acid collector,but also enhance the collecting performance of oleic acid at low temperature,which can realize the flotation of the ores at a low temperature and play an important role in saving energy to some extent.Compared with oleic oil,the benzohydroxamic acid had a great advantage in removing iron from potash feldspar,a potash feldspar concentrate with Fe grade of 0.23%,K2O grade of 12.59%and Na2O grade of 0.26%was obtained by flotation with Yb105 as collector,and the yield of the concentrate was 82.55%.
基金Project(50804055) supported by the National Natural Science Foundation of China
文摘The chemical nature of the interaction of starch and dodecylamine （DDA）, which generally act as depressant and collector, respectively, in the reverse flotation of bauxite, was investigated using starch-iodine tests. The results obtained from the blue-value measurements for starch＋DDA＋iodine system indicate the formation of the inclusion complex for amylose-DDA system at low DDA concentration （〈2 retool/L）. However, it is less likely for amylopectin-DDA system with short helix. UV-Vis spectra of starch-iodine complexes show that each helix of amylose can accommodate two DDA molecules locating separately at its two ends, and in the helical cavity there is room available for the upcoming iodine. When concentrated DDA is tested, amylose-DDA system exhibits no characteristic starch-iodine color, owing to the presence of a compact coating of DDA molecules on starch via hydroxyl/amine hydrogen bonding. ^1H NMR spectroscopy and surface tension determination help to clarify the interaction mechanism of amylose with DDA.
