Technical field: used in water desalting for sea water or brackish water and all fields which reverse osmosis used for even in smaller scales .

Background Art: reverse osmosis is water purification technology that use semi permeable membrane to remove ions , molecules from drinking water by applying pressure to overcome osmotic pressure and move the water from the solution side to pure water side of the membrane under very high pressure disadvantage of reverse osmosis

1- its need very high pressure for sea water desalting from 40 to 82 bar

2- While its use low energy around 3kwh \ m3 but its still large

3- Membrane fouling

4-small scale unite use a lot of water and low recovery

5- very low rate of filtration as the pore size is only 0.1 nm

The new in the invention subject

- the filtration occur through a filter of larger pore size of actual from 1 nm to 10 nm or even more . although its larger than the size of hydrated ions but this ions cant pass through by anew technology depending of electrical double layer filtration

2-as its occur in larger pore size than all species in the solutions osmotic pressure don't work and don't resist the process so we need lower pressure and so lower energy requirement and lower resistance of filter so we have also very high rat of processing. 3- the filter of conductive materials like metals so its may subjected to lower fouling.

Disclosure Of Invention: detailed description of the invention The theory of the invention: when placing a charged negative plate in saline solution an electrical double layer formed as in figure 1 the first layer (1) is formed of solvent molecule calld inner helmholtz plane and act as dielectric the second layer is first layer of hydrated cations which called outer helmholtz plane or stem layer which is stationary the next layer of hydrated cations is the diffuse layer where the cations still attracted to the negative plate but its can move away for some distance under thermal motion if we have two plates charged with negative charge and placed close together to fuse the two electrical double layers at diffuse layers without presence of the bulk of the solution so the diffuse layers diffused and the two electrodes ctually are the walls of the pore or channel in the filter which is full of this pores as in figure 2-b so pore contain in the middle of it a diffuse layer .

-if this channel or pore is churched with negative church with placed in a cup contain solution and moved through anions cant pass as its repeal with the filter as its carry the same charge the cations of the solutions push the cations of the diffuse layer and replace it freely but if this cannel is placed between two separated rooms one Contain saline and the other contain pure water and put pressure on saline solution .

anions can’t pass cations also can’t pass as its try to push cations in the electrical double layer to replace it but this cations will resist and don’t enter pure water tank as there is no counter ions to receive it an neutralize it and also its still attracted to the negative plate and if some of it pass the channel under pressure its leave behind the anions which can’t pass but from anion cloud which will prevent further cations from entering the cannel only water can pass the channel freely.

-the size of pores in the membrane should be equal and with the same size as calculated to achieve diffusion of double layer in the plane of slipping plane of diffuse double layer . of course this cant be done so we have to pass in the filter suspensions which its partials is exactally larger than the required size to block larger pore in preparing the filter an during maintain one first embodiment like in figure (3) and (4) a advise consist of three separated rooms the middle tank (3) conation the sea water and this room is separated from the right pure water tank (2)by a filter (6) of conductive material like metal connected to the negative terminal of a battery and separated from lift pure water tank (3) by another filter (5) of conductive material like metal connected to the positive terminal of the battery at a voltage under 1.4 volt the feed enter to (1) and pure water exit from (8) and (9) while the concentrate exit from (7) explanation at the molecular level or one pore only the diameter of the pore of the filter should be calculated to ensure just fusing of double layers in the level of slipping plane and this depend on the debye length which depend on the voltage of the electrode which cant exceed the decomposition voltage of saline from 1.2 to 1.4 voltage and also depend on concentration and temperature if the stem layer of hydrated ions is lnm so the minimum size of the pore is 3 nm as 1 nm for uper and lower stern and one for diffuse layer

-when pressure applied on saline solution side what happen near the negative charge filter is the anions can’t pass as its repeal with the filter cations of bulk solutions push cations in diffuse layer in the pore but the later cations can’t leave its place as there is no anions in pure water side to neutralize it It’s still attracted to the negative plate

When some cations pass under pressure the channel its leave behind the anions(l 1) which form a cloud extract cations from the channel and prevent further cations from entering the channel only water molecules can pass freely through the diffuse layer from room (4) to room (2) and (3) under hydraulic pressure the same occur in left side but with reverse polarity and water only pass the negative filter to room (3) concentrate exit from (10) important note osmosis don't resist the desalination process as the pore size is larger than all species but only the simple diffusion mechanism according to ficks low will resist

The second embodiment in figure (5) its depend on capacitor like design where only one room for pure water (6) which separated from saline room (7) by a filter contain a channels or pores charged negative charge to form the cathode while the other electrode is immersed in the solution of sea water may be of any conductive metal or carbon which act as anode of the capacitor attract the anions of the solutions around it at the cathode which is our filter the same occur as first design exactly and pure water pass under pressure to room (6) this design is simple and we use one filter only and one room only to collect pure water we can reverse the polarity to choose which the volume of anions or cations is much more suitable to pore size or prevent corrosion of the filter and fouling the third embodiment is like the second but in the form of aluminum or tantalum electrolytic capacitor where the filter is the anode (3) which is connected to positive terminal of the battery consist of aluminum which is covered by oxide layer (8) to serve to act as dielectric instead of the molecules of the solvent, and the other plate is aluminum foil immersed in saline side act to connect the electricity only to the solution which act as a cathode itself the thickness of the oxide layer on the anode can be increased by preparing in higher voltage and this help to use higher voltage greater than the decomposition of the solution freely as the electrical double layer began at the end of the oxide layer opposite to the solution so we can get thicker double layer and of course larger pore size which can reach from 4 nm to even 10 nm or more so higher efficacy of the process by using higher voltage

Sea water enter from (1) to room (7) under hydrostatic pressure and only pure water pass the filter (3)to room (6)and exit

-as we explained earlier cations cant pass and anions resist pushing by anions from saline side as no counter ion in pure water tank (7) to neutralize it and its still attracted to the positive plate and to the cations cloud which leave behind only water can pass freely this design give us ability to use higher voltage as the oxide layer thickness can be designed to withstand with higher voltage than the solvent molecules in inner helm holtez plane so we can use greater pore size as debye length depend on the voltage so we can use grater pore size and so higher efficacy and rat saline water enter from (1) to room (7) and only water can pass the filter (3) to room (6).

Brief description of the drawing:

Figure 1

1 -inner Helmholtz plane

2-outen Helmoltz plane

3 -solvated ions (cations)

4-diffus layer

5-solvent molevule

6-solide electrode This figure show the electric oublet layer whoch occur 8 round electrode in solution

Figure 2-a

Is a TS in a single poreact as channel in the filter where fusion of the two electric double layer occur to form a fusion region in the middle at the slipping plane

1- inner Helmoltz plane

2-diffus layer

3 -outer Helmoltz plane

4-wall of the changed channel

Figure 2- b

Is TS in the wall the filter it self 1 -a channel or pare

2-wall of the filter

3 -wire to connect an electric change

Figure 3

1 -saline water tank

2 and 3 pure water tank

4-feed of saline water

5 -pore with positive charge

6-pore with negative charge

7-concentrat outlet 8,9- fresh water outlet 10-stem layer 1 1 -anion cloud

12-cation cloud

13 -diffuse layer

Sea or saline water enter from 4 under high pressure to 1 and concentrate exit from 7 water only pass the two filters toward 2 and 3 where pure water exit from 8 and 9

The two filters or pores one connected to a battery at 1.4 volt

Near the cathode

A nions are repealed away from the filter and cannt pass

Cotion cannt pass also as its attracted to negative electrode and to the anions cloud (1 1) and water only can pass

Figure (4)

For device of figure (3) and show that real separation between saline room and fresh water room is the two filters (5) and which was represented in figure (3) by a single pore

Figure (5)

1-Feed of saline water 2-positive electrode

3 -negative filter or pore

4-stem layer

5-diffuse layer

6-pure or fresh water tank

7-tank of saline water

Feed of saline water enter from 1 to 7 and pure water pass the filter 3 which is represented by a pore to (6) . the filter is connected to negative terminal of the battery while the positive is connected to electrode 2 which is immersed in the saline solution side to form the other plate which held anions near it

Figure (6)

1- Feed entry.

2- Negative electrode aluminium.

3- Positive electrode filter.

4- Stern layer.

5- diffuse layer.

6- Pure water tank.

7- Saline water tank.

8- Dielectric of AL2 03

9- Cation cloud.

Saline water enter from 1 to room 7 and only pure water from the pare 3 to pare water tank.

The filter act as anode of aluminium electrolyte capicitor which is covered by oxide layer (8) acting as dielectric.

The other foil (2) act as conductive to the current to the solution

Anions form electric double layer in the pore of the anode filter water only con pass the filter as shown. through the diffuse layer cations cloud 9 prevent further anions from escaping to pore to room (6) of pure water tank.