Methyl isobutyl ketone(MIBK) is widely used as extraction agent in hydrometallurgy. As it has a definite solubility in water, so when using MIBK as extraction agent, there will be MIBK in stripping solutions inevitabl...Methyl isobutyl ketone(MIBK) is widely used as extraction agent in hydrometallurgy. As it has a definite solubility in water, so when using MIBK as extraction agent, there will be MIBK in stripping solutions inevitably, which not only pollutes working conditions, but also affects the quality of ultimate product. In order to remove MIBK from aqueous solutions, the means of flat vacuum membrane distillation(VMD) is studied in the paper. The area of the membrane used in the study is 0.02 m 2, the initial volume of feed is 2 L, each experiment was conducted over a time period of 60 120 min. The influences of the factors such as temperature(34.8 55.0 ℃); pressure in the permeate side(10.67 14.67 kPa) and feed flow rate(27.8 69.4 mL/s) were experimentally studied. Increasing the temperature or reducing the pressure in the permeate side results in a faster removal of MIBK; however there is a decrease in removal factor β , increasing the feed flow rate results in a faster removal of MIBK and an increase of removal factor β , especially in the range of lower flow rate. The study indicates that the aim of MIBK removal and recycle from dilute aqueous solutions can be achieved by VMD.展开更多
Concentrating sulfuric acid solution by vacuum membrane distillation with flat PEFE membrane is explored. The effects of sulfuric acid concentration, temperature of the feed, the vacuum degree of the vacuum side on th...Concentrating sulfuric acid solution by vacuum membrane distillation with flat PEFE membrane is explored. The effects of sulfuric acid concentration, temperature of the feed, the vacuum degree of the vacuum side on the flux of membrane distillation and the separation efficiency of acid are investigated. The results illustrate that the flux of the membrane distillation increases with the rise of feed temperature and the vacuum degree of the vacuum side, but it decreases with the rise of the sulfuric acid concentration of the feed. The separation efficiency of acid is correlated with the flux of membrane distillation; the separation efficiency of the acid can amount to 100% in the process, when operative conditions are properly controlled. It can also been obtained from the experiment that, compared with other methods of membrane distillation, the vacuum membrane distillation can obtain greater distillation flux.展开更多
concentrating sulfuric acid by membrane distillation in a flat sheet direct contact membrane distillation device with a self made metal PTFE composite membrane has been studied. The effect of sulfuric acid concentrati...concentrating sulfuric acid by membrane distillation in a flat sheet direct contact membrane distillation device with a self made metal PTFE composite membrane has been studied. The effect of sulfuric acid concentration of feed, the flowrate and liquor temperature in high temperature side and low temperature side on the flux and separation efficiency is investigated. The stability of this composite membrane is also inspected. The experimental results show that the metal PTFE composite membrane can be used in membrane distillation, and its properties are very stable. It is feasible to concentrate sulfuric acid by membrane distillation with this membrane.展开更多
文摘Methyl isobutyl ketone(MIBK) is widely used as extraction agent in hydrometallurgy. As it has a definite solubility in water, so when using MIBK as extraction agent, there will be MIBK in stripping solutions inevitably, which not only pollutes working conditions, but also affects the quality of ultimate product. In order to remove MIBK from aqueous solutions, the means of flat vacuum membrane distillation(VMD) is studied in the paper. The area of the membrane used in the study is 0.02 m 2, the initial volume of feed is 2 L, each experiment was conducted over a time period of 60 120 min. The influences of the factors such as temperature(34.8 55.0 ℃); pressure in the permeate side(10.67 14.67 kPa) and feed flow rate(27.8 69.4 mL/s) were experimentally studied. Increasing the temperature or reducing the pressure in the permeate side results in a faster removal of MIBK; however there is a decrease in removal factor β , increasing the feed flow rate results in a faster removal of MIBK and an increase of removal factor β , especially in the range of lower flow rate. The study indicates that the aim of MIBK removal and recycle from dilute aqueous solutions can be achieved by VMD.
文摘Concentrating sulfuric acid solution by vacuum membrane distillation with flat PEFE membrane is explored. The effects of sulfuric acid concentration, temperature of the feed, the vacuum degree of the vacuum side on the flux of membrane distillation and the separation efficiency of acid are investigated. The results illustrate that the flux of the membrane distillation increases with the rise of feed temperature and the vacuum degree of the vacuum side, but it decreases with the rise of the sulfuric acid concentration of the feed. The separation efficiency of acid is correlated with the flux of membrane distillation; the separation efficiency of the acid can amount to 100% in the process, when operative conditions are properly controlled. It can also been obtained from the experiment that, compared with other methods of membrane distillation, the vacuum membrane distillation can obtain greater distillation flux.
文摘concentrating sulfuric acid by membrane distillation in a flat sheet direct contact membrane distillation device with a self made metal PTFE composite membrane has been studied. The effect of sulfuric acid concentration of feed, the flowrate and liquor temperature in high temperature side and low temperature side on the flux and separation efficiency is investigated. The stability of this composite membrane is also inspected. The experimental results show that the metal PTFE composite membrane can be used in membrane distillation, and its properties are very stable. It is feasible to concentrate sulfuric acid by membrane distillation with this membrane.