Since wolframite is usually associated with calcite,the separation and enrichment of wolframite by froth flotation remains a great challenge.Herein,a novel trisiloxane surfactant N-(2-aminoethyl)-3-ami nopropyltrisilo...Since wolframite is usually associated with calcite,the separation and enrichment of wolframite by froth flotation remains a great challenge.Herein,a novel trisiloxane surfactant N-(2-aminoethyl)-3-ami nopropyltrisiloxane(AATS)was successful synthesized,which was used for the separation of wolframite from calcite for the first time.The flotation separation performance of AATS was studied by flotation test,and its adsorption mechanism was explored based on contact angle,infrared spectrum analysis(FTIR),zeta potential and density functional theory(DFT)calculation.The results of microflotation test and binary mixed ore flotation test pointed that AATS had excellent selectivity and more prominent collection capacity for the flotation of wolframite when compared with industrial reagent sodium oleate(NaOL).The measurement results of contact angle proved that AATS improved the hydrophobicity of the wolframite surface.The highly selective adsorption mechanism of AATS surfactant on mineral surfaces were further researched and analyzed by FTIR and zeta potential.The results revealed that AATS surfactant had significant adsorption effect on wolframite,yet almost no adsorption on calcite.DFT calculation indicated that AATS produced electrostatic adsorption with wolframite surface through—N+H3 group.展开更多
以丁炔二醇醚(BEO)和环氧氯丙烷为原料,在四氯化锡的催化作用下,开环醚化生成氯醇醚(BAE),然后与三乙胺发生季铵化反应得到季铵盐型氯醇醚(QASBAE)中间体,最后在铂催化剂的作用下,与1,1,1,3,5,5,5-七甲基三硅氧烷(MDHM)进行硅氢化加成...以丁炔二醇醚(BEO)和环氧氯丙烷为原料,在四氯化锡的催化作用下,开环醚化生成氯醇醚(BAE),然后与三乙胺发生季铵化反应得到季铵盐型氯醇醚(QASBAE)中间体,最后在铂催化剂的作用下,与1,1,1,3,5,5,5-七甲基三硅氧烷(MDHM)进行硅氢化加成反应生成目标产物季铵盐型阳离子型三硅氧烷双子表面活性剂(QASBTSS)。用FT-IR和1HNMR对目标产物的结构进行了表征,并通过测定其水溶液的平衡表面张力对其界面性能进行了研究。结果表明,在临界胶束为6.56×10-4 mol·L-1时,可以将水的表面张力降低至22.48 m N·m-1。展开更多
The C-H stretch vibrational spectra of the trisiloxane superspreading surfactant Silwet L-77 （（CH3）3Si- O-Si（CH3）（C3H6）（OCH2CH2）7-8OCH3）-O-Si（CH3）3） at the air/water interface are measured with the surfac...The C-H stretch vibrational spectra of the trisiloxane superspreading surfactant Silwet L-77 （（CH3）3Si- O-Si（CH3）（C3H6）（OCH2CH2）7-8OCH3）-O-Si（CH3）3） at the air/water interface are measured with the surface Sum Frequency Generation Vibrational Spectroscopy （SFG-VS）. The spectra are dominated with the features from the -Si-CH3 groups around 2905 cm^-1 （symmetric stretch or SS mode） and 2957 ^-1 （mostly the asymmetric stretch or AS mode）, and with the weak but apparent contribution from the -O-CH2- groups around 2880 ^-1 （symmetric stretch or SS mode）. Comparison of the polarization dependent SFG spectra below and above the critical aggregate or micelle concentration （CAC） indicates that the molecular orientation of the C-H related molecular groups remained unchanged at different surface densities of the Silwet L-77 surfactant. The SFG-VS adsorption isotherm suggested that there was no sign of Silwet L-77 bilayer structure formation at the air/water interface. The Gibbs adsorption free energy of the Silwet surfactant to the air/water interface is -42.2±0.8kcal/mol, indicating the unusually strong adsorption ability of the Silwet L-77 superspreading surfactant.展开更多
在铂催化下,1,1,1,3,5,5,5-七甲基三硅氧烷(MDHM)和烯丙基聚氧乙烯聚氧丙烯醚(F6)经硅氢加成反应制得羟基封端聚醚改性三硅氧烷(HPEMTS),再与马来酸酐(MA)进行酯化反应合成了一种新型非离子三硅氧烷双子表面活性剂(NTSGS).用红外光谱(IR...在铂催化下,1,1,1,3,5,5,5-七甲基三硅氧烷(MDHM)和烯丙基聚氧乙烯聚氧丙烯醚(F6)经硅氢加成反应制得羟基封端聚醚改性三硅氧烷(HPEMTS),再与马来酸酐(MA)进行酯化反应合成了一种新型非离子三硅氧烷双子表面活性剂(NTSGS).用红外光谱(IR)对NTSGS的结构进行了表征,并对NTSGS的界面性能、发泡力、耐酸碱盐稳定性和在硬水中的稳定性等进行了测定.结果表明:NTSGS水溶液的临界胶束浓度(cmc)为2.0 g/L,表面张力(γcmc)为25.3 m N/m.质量分数为0.1%的NTSGS水溶液发泡力为1.17,5 min稳泡性为0.200.NTSGS溶液耐酸碱盐等化学稳定性好,在硬水中的稳定性为4级.展开更多
基金This work was supported by the Natural Science Foundation of Jiangxi,China(Nos.20202ACBL213008 and 20202ZDB01005)。
文摘Since wolframite is usually associated with calcite,the separation and enrichment of wolframite by froth flotation remains a great challenge.Herein,a novel trisiloxane surfactant N-(2-aminoethyl)-3-ami nopropyltrisiloxane(AATS)was successful synthesized,which was used for the separation of wolframite from calcite for the first time.The flotation separation performance of AATS was studied by flotation test,and its adsorption mechanism was explored based on contact angle,infrared spectrum analysis(FTIR),zeta potential and density functional theory(DFT)calculation.The results of microflotation test and binary mixed ore flotation test pointed that AATS had excellent selectivity and more prominent collection capacity for the flotation of wolframite when compared with industrial reagent sodium oleate(NaOL).The measurement results of contact angle proved that AATS improved the hydrophobicity of the wolframite surface.The highly selective adsorption mechanism of AATS surfactant on mineral surfaces were further researched and analyzed by FTIR and zeta potential.The results revealed that AATS surfactant had significant adsorption effect on wolframite,yet almost no adsorption on calcite.DFT calculation indicated that AATS produced electrostatic adsorption with wolframite surface through—N+H3 group.
文摘以丁炔二醇醚(BEO)和环氧氯丙烷为原料,在四氯化锡的催化作用下,开环醚化生成氯醇醚(BAE),然后与三乙胺发生季铵化反应得到季铵盐型氯醇醚(QASBAE)中间体,最后在铂催化剂的作用下,与1,1,1,3,5,5,5-七甲基三硅氧烷(MDHM)进行硅氢化加成反应生成目标产物季铵盐型阳离子型三硅氧烷双子表面活性剂(QASBTSS)。用FT-IR和1HNMR对目标产物的结构进行了表征,并通过测定其水溶液的平衡表面张力对其界面性能进行了研究。结果表明,在临界胶束为6.56×10-4 mol·L-1时,可以将水的表面张力降低至22.48 m N·m-1。
文摘The C-H stretch vibrational spectra of the trisiloxane superspreading surfactant Silwet L-77 （（CH3）3Si- O-Si（CH3）（C3H6）（OCH2CH2）7-8OCH3）-O-Si（CH3）3） at the air/water interface are measured with the surface Sum Frequency Generation Vibrational Spectroscopy （SFG-VS）. The spectra are dominated with the features from the -Si-CH3 groups around 2905 cm^-1 （symmetric stretch or SS mode） and 2957 ^-1 （mostly the asymmetric stretch or AS mode）, and with the weak but apparent contribution from the -O-CH2- groups around 2880 ^-1 （symmetric stretch or SS mode）. Comparison of the polarization dependent SFG spectra below and above the critical aggregate or micelle concentration （CAC） indicates that the molecular orientation of the C-H related molecular groups remained unchanged at different surface densities of the Silwet L-77 surfactant. The SFG-VS adsorption isotherm suggested that there was no sign of Silwet L-77 bilayer structure formation at the air/water interface. The Gibbs adsorption free energy of the Silwet surfactant to the air/water interface is -42.2±0.8kcal/mol, indicating the unusually strong adsorption ability of the Silwet L-77 superspreading surfactant.
文摘在铂催化下,1,1,1,3,5,5,5-七甲基三硅氧烷(MDHM)和烯丙基聚氧乙烯聚氧丙烯醚(F6)经硅氢加成反应制得羟基封端聚醚改性三硅氧烷(HPEMTS),再与马来酸酐(MA)进行酯化反应合成了一种新型非离子三硅氧烷双子表面活性剂(NTSGS).用红外光谱(IR)对NTSGS的结构进行了表征,并对NTSGS的界面性能、发泡力、耐酸碱盐稳定性和在硬水中的稳定性等进行了测定.结果表明:NTSGS水溶液的临界胶束浓度(cmc)为2.0 g/L,表面张力(γcmc)为25.3 m N/m.质量分数为0.1%的NTSGS水溶液发泡力为1.17,5 min稳泡性为0.200.NTSGS溶液耐酸碱盐等化学稳定性好,在硬水中的稳定性为4级.
