A column-switching anion-exchange chromatography method was described for the separation and determination of petroleum monosulfonates (PMS) and petroleum disulfonates (PDS) in crude oil that was simply diluted wi...A column-switching anion-exchange chromatography method was described for the separation and determination of petroleum monosulfonates (PMS) and petroleum disulfonates (PDS) in crude oil that was simply diluted with the dichloromethane/methanol (60/40). The high performance liquid chromatography (HPLC) system consisted of a clean-up column and an analytical column, which were connected with two six-port switching valves. Detection of petroleum sulfonates was available and repeatable. This method has been successfully applied to determine PMS and PDS in crude oil samples from Shengli oil field.展开更多
Flotation performance of a de-slimed(-150+53μm)Jordanian siliceous phosphate was evaluated in a batch laboratory flotation column 100 cm high and 5 cm inside diameter.The collector used during anionic flotation wa...Flotation performance of a de-slimed(-150+53μm)Jordanian siliceous phosphate was evaluated in a batch laboratory flotation column 100 cm high and 5 cm inside diameter.The collector used during anionic flotation was sodium oleate while an amine acetate(AEROMINE 3100C)was used for cationic flotation.Flotation comparison at different collector dosage,superficial gas velocity,and frother concentration showed that the maximum difference in performance between cationic and anionic flotation was obtained with these flotation parameters:30×10^(-6)(mg/L)frother concentration,250 g/t collector concentration,and 3.4 cm/s superficial gas velocity.At these operating conditions amine (cationic)flotation gave 7%higher flotation recovery,a 6%cleaner concentrate grade,and was 6%more efficient at removing silica.展开更多
Octadecylsilanized silica (ODS) was coated with meso-octamethylcalix[4]pyrrole to obtain a novel calix[4]pyrrole containing stationary phase for HPLC. Compared to ODS, the new stationary phase showed a relatively larg...Octadecylsilanized silica (ODS) was coated with meso-octamethylcalix[4]pyrrole to obtain a novel calix[4]pyrrole containing stationary phase for HPLC. Compared to ODS, the new stationary phase showed a relatively large retention and an improved separation for phenolic compounds and organic anions, using pure water as mobile phase. The results can be ascribed to the interaction between analytes and calix[4]pyrrole.展开更多
Methacrylate-based monolithic column was prepared in fused-silica capillary (80 ′ 0.32 mm i.d.) by in situ polymerizetion reaction using glycidyl methacrylate as monomer;ethylene dimethacrylate as crosslinker;1-propa...Methacrylate-based monolithic column was prepared in fused-silica capillary (80 ′ 0.32 mm i.d.) by in situ polymerizetion reaction using glycidyl methacrylate as monomer;ethylene dimethacrylate as crosslinker;1-propanol, 1,4-butanediol, and water as porogenic solvents. The monolith matrix was modified with trimethylamine to create strong anion exchanger via ring opening reaction of epoxy groups. The morphology of the monolithic column was studied by using Scanning Electron Microscope (SEM). This column had good mechanical stability and permeability. The effects of various mobile phases for separation of inorganic anions were investigated. Iodate, bromate, nitrite, bromide, and nitrate were separated within 11 min using100 mMpotassium chloride as mobile phase and detected at 210 nm. This method showed good precision of retention time, acceptable linearity and good sensitivity. Under the optimum condition, the RSD of the retention time was in the range of 1.09%-1.75% (n = 6). The calibration curve showed linear relationships between the peak area and the concentration. The limits of detection (LOD) and the limits of quantitation (LOQ) were between 0.08-0.18 mM and 0.26-0.61 mM, respectively. This method was applied to the determination of inorganic anions in tap water and ground water samples.展开更多
基金the National Nature Science Foundation of China(No.20675085)the support from the Program of the Light in China's Western Region(2003)the Province Nature Science Foundation of Gansu(No.3ZS041-A25-23).
文摘A column-switching anion-exchange chromatography method was described for the separation and determination of petroleum monosulfonates (PMS) and petroleum disulfonates (PDS) in crude oil that was simply diluted with the dichloromethane/methanol (60/40). The high performance liquid chromatography (HPLC) system consisted of a clean-up column and an analytical column, which were connected with two six-port switching valves. Detection of petroleum sulfonates was available and repeatable. This method has been successfully applied to determine PMS and PDS in crude oil samples from Shengli oil field.
基金done during the first author's Fulbright fellowship at the Center for Advanced Separation (CAST)/Virginia Technical Institute and State University-USA. Salah would like to thank all the people who work at CAST for their friendship and support during his stay in Blacksburg, VA.
文摘Flotation performance of a de-slimed(-150+53μm)Jordanian siliceous phosphate was evaluated in a batch laboratory flotation column 100 cm high and 5 cm inside diameter.The collector used during anionic flotation was sodium oleate while an amine acetate(AEROMINE 3100C)was used for cationic flotation.Flotation comparison at different collector dosage,superficial gas velocity,and frother concentration showed that the maximum difference in performance between cationic and anionic flotation was obtained with these flotation parameters:30×10^(-6)(mg/L)frother concentration,250 g/t collector concentration,and 3.4 cm/s superficial gas velocity.At these operating conditions amine (cationic)flotation gave 7%higher flotation recovery,a 6%cleaner concentrate grade,and was 6%more efficient at removing silica.
基金supported by the National Natural Science Foundation of China(NO.20275041)
文摘Octadecylsilanized silica (ODS) was coated with meso-octamethylcalix[4]pyrrole to obtain a novel calix[4]pyrrole containing stationary phase for HPLC. Compared to ODS, the new stationary phase showed a relatively large retention and an improved separation for phenolic compounds and organic anions, using pure water as mobile phase. The results can be ascribed to the interaction between analytes and calix[4]pyrrole.
文摘Methacrylate-based monolithic column was prepared in fused-silica capillary (80 ′ 0.32 mm i.d.) by in situ polymerizetion reaction using glycidyl methacrylate as monomer;ethylene dimethacrylate as crosslinker;1-propanol, 1,4-butanediol, and water as porogenic solvents. The monolith matrix was modified with trimethylamine to create strong anion exchanger via ring opening reaction of epoxy groups. The morphology of the monolithic column was studied by using Scanning Electron Microscope (SEM). This column had good mechanical stability and permeability. The effects of various mobile phases for separation of inorganic anions were investigated. Iodate, bromate, nitrite, bromide, and nitrate were separated within 11 min using100 mMpotassium chloride as mobile phase and detected at 210 nm. This method showed good precision of retention time, acceptable linearity and good sensitivity. Under the optimum condition, the RSD of the retention time was in the range of 1.09%-1.75% (n = 6). The calibration curve showed linear relationships between the peak area and the concentration. The limits of detection (LOD) and the limits of quantitation (LOQ) were between 0.08-0.18 mM and 0.26-0.61 mM, respectively. This method was applied to the determination of inorganic anions in tap water and ground water samples.