RU1789253C - Membrane cell - Google Patents

Abstract

The invention relates to devices for separating solutions using semipermeable membranes and can be used to study the characteristics of semipermeable membranes. The purpose of the invention is to increase the accuracy of studies of the characteristics of semi-permeable membranes by reducing the concentration polarization while ensuring uniformity, changing the speed and direction of flow. The cell contains a housing, the cover and bottom of which are made of electrically insulating material, and the side walls of electrically conductive material. The membrane and the drainage element are also made in the form of a ring and placed in the housing. The main difference is that the device for mixing the solution is made in the form of a magnet, a cell is placed between the poles, and the poles of a DC source are connected to the side walls of the housing. The interaction of dissociated salt ions simultaneously with the electric and magnetic fields leads to their movement along the body, which gradually drives the entire volume of the solution. 1 ill. ate with

Description

The invention relates to devices for separating solutions using semi-permeable membranes by reverse osmosis and, in particular, to devices for studying the characteristics of semi-permeable membranes.

The purpose of the invention is to increase the accuracy of studies of the characteristics of semipermeable membranes by reducing the concentration polarization while ensuring a uniform change in the speed and direction of flow.

The drawing shows a schematic diagram of a cell for studying the characteristics of semipermeable membranes.

The membrane cell contains an annular hollow body 1, including

the outer and inner side walls 2 and 3, made of electrically conductive material, the cover 4 and the bottom 5, made of electrical insulating material having electrochemical resistance, the porous substrate 6 is tightly clamped together with the studied semipermeable membrane 7 located above it in the bottom holes 8. The device also contains a permanent magnet or electromagnet 9 with a coil 10, a constant current source 11 (for example, an AC to DC converter), a switch 12 and a regulator 13 Torr voltage. The outer and inner side walls 2 and 3 are connected through the switch 12 of the reverse polarity to the first

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the (adjustable) output 14 of the direct current source 11, to the second output 15 of which is connected the coil 10 of the electromagnet 9. The voltage regulator 13 is included in the control circuit of the direct current source 11. The housing 1 of the device is equipped with nozzles 16 and 17 for supplying and discharging a salt-containing solution, a nozzle 18 for draining the permeate, and a nozzle 19 for connecting the housing 1 with a high pressure source, as a rule, of compressed gas.

The device operates as follows. A semipermeable membrane 7 is installed in the bottom hole 8 of the housing 1 above the porous substrate 6. The membrane is tested. The membrane with the substrate is tightly clamped between the flanges of the side walls 2 and 3 on the one hand and the bottom flanges 5 on the other. The housing 1 is filled with a saline solution through a nozzle. Through inlet 19, inert gas is supplied into the housing 1 under pressure, thereby creating the necessary solution pressure on the membrane 7. Turn on the power and supply, for example

direct current - from the first output

14 of the current transducer 11 through the switch 12 to the side walls 2 and 3 of the housing 1, and from the second output 15 of the current transducer 11 to the coil 10 of the electromagnet 9. The salt anions dissociated in the solution under the influence of the electric field begin to move towards the positively charged external side walls 2, and cations - in the opposite direction to the negatively charged inner side wall 3. Interaction with directed perpendicular to the movement of ions

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the magnetic field created by the electromagnet 9, the ions experience the action of forces that change the direction of their movement. Hydrated ions move along the annular channel of the housing 1 and entrain the solvent. The flow of the solution flows uniformly along the membrane 7. The flow rate is changed by correcting the voltage on the side walls 2 and 3 using the voltage regulator 13. The direction of movement of the solution is changed by reversing the polarity of the side walls 2 and 3 using the switch 12. Changing the pressure, speed and direction of movement of the solution, the characteristics of semi-permeable membranes are studied by known methods — salt retention, water resistance, etc. Permeate is removed from the device through pipe 18. at the end of the separation process, the pressure and power are turned off and the solution is drained from the housing 1 through the pipe 17,

The use of the invention improves productivity and separation quality, i.e. the accuracy of studies of the characteristics of semipermeable membranes by reducing the influence of concentration polarization while ensuring a uniform solution flow along the membrane surface, which is achieved by the absence of mechanical stirrers and the annular shape of the body. In addition, accuracy is enhanced by the possibility of carrying out a series of experiments at various flow rates of the solution and changing the direction of its movement. The maintenance of the device is also simplified.

Claims (1)

The claims A membrane cell containing a housing with nozzles for supplying and discharging a separable solution, permeate outlet and a supply of compressed gas, a drainage element, a semipermeable membrane and a device for mixing the solution, characterized in that, in order to improve the accuracy of studies, the characteristics of semipermeable membranes by lowering concentration polarization while ensuring uniformity, change in speed and direction of flow of the solution flow, the body is made in the form of a hollow ring, the cover and bottom of which are made of electrically insulating material, and the side walls are made of electrically conductive material, and the mixing device is made of a magnet, the poles of which are located above the cover both under the bottom of the housing and from a constant current source whose poles are connected to the side walls of the housing. nineteen CHN hP 7 V