1. A method for producing monodisperse ion exchangers having chelating functional groups represented by the structural formula (I)
where is the polymer backbone and R1 and R2 independently of one another are hydrogen or a
group with a degree of substitution
in the range of 1.4-1.99 (including end values), comprising the steps of:
a) forming monodisperse crosslinked polymer beads via reacting monomer droplets of at least one monovinylaromatic compound, at least one polyvinylaromatic compound, at least one porogen, and at least one initiator or an initiator combination, wherein a jetting process andor a seed-feed process is employed,
b) phthalimidomethylating the monodisperse crosslinked polymer beads with phthalimide derivatives present in inert solvent and comprising an SO3 adduct, wherein said phthalimidomethylating comprises introducing a subportion of from 1 to 15% by weight of the monodisperse crosslinked polymer beads into the SO3 adduct and stirring at a temperature of less than or equal to 35\xb0 C. for 1 to 15 hours, wherein the amount of free SO3 is from 0.28 to 0.65 mol based on 1 mol of phthalimide and thereafter introducing the residual amount of monodisperse crosslinked polymer beads into the SO3 adduct at a temperature of from 30 to 75\xb0 C., thereby forming phthalimidomethylated polymer beads,
c) converting the phthalimidomethylated polymer beads to aminomethylated polymer beads, and
d) reacting the aminomethylated polymer beads to introduce chelating groups, thereby forming said monodisperse ion exchangers having chelating functional groups represented by the structural formula (I).
2. The monodisperse ion exchangers having chelating functional groups formed by the method according to claim 1.
3. The monodisperse ion exchangers according to claim 2 further having a total capacity of from 3.1 to 3.9 moll and having a median pore diameter of from 75 to 85 nm.
4. A method for the adsorbtion of metals from aqueous solutions and organic liquids comprising: contacting the aqueous solutions and the organic liquids with the chelating exchangers according to claim 2, whereby the metals are adsorbed.
5. The method according to claim 4, wherein the metals are selected from the group consisting of alkaline earth metals, heavy metals, noble metals, and combinations thereof.
6. The method according to claim 4, wherein the aqueous solutions are solutions of alkaline earth metals, solutions of alkali metals or brines for alkali metal chloride electrolysis.
7. The method according to claim 4, wherein the metals are alkaline earth metals from brines employed for alkali metal chloride electrolysis.
8. The method according to claim 5, wherein the heavy metals and noble metals are selected from the group consisting of mercury, iron, cobalt, nickel, copper, zinc, lead, cadmium, manganese, uranium, vanadium, elements of the platinum group, gold and silver.
9. The method according to claim 4, wherein the alkaline earth metals are selected from the group consisting of the metals magnesium, calcium, strontium and barium.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An aircraft potable-water system comprising:
a storage tank that is full when it contains a set amount of potable water and not full when it contains less than this amount;
a ground-fill line having an upstream end adapted for connection to an external potable-water source and a downstream end communicating with the storage tank;
an overflow line having an upstream end communicating with the storage tank andor the ground-fill line and a downstream end communicating with a drain;
a valve movable between an overflow-open position whereat potable water is not blocked from draining through the drain and an overflow-closed position whereat potable water is blocked from draining through the drain; and
wherein the valve automatically moves andor remains in its overflow-open position when storage tank is full and automatically moves andor remains in its overflow-closed position when the storage tank is not full.
2. An aircraft potable-water system as set forth in claim 1, wherein the drain is a drainmast.
3. An aircraft potable-water system as set forth in claim 1, further comprising a switch that automatically converts between a full condition when the storage tank is full and a not-full condition when the storage tank is not full;
wherein the conversion of the switch to the full condition causes the valve to move to its overflow-open position so that potable water can drain through the drain.
4. An aircraft potable-water system as set forth in claim 3, wherein the switch senses the level of the potable water contained in the tank and converts to its full condition when the potable water reaches a predetermined level corresponding to the storage tank being full.
5. An aircraft potable-water system as set forth in claim 4, wherein the switch comprises a sleeve that is sealed when the switch is in its full condition and a vent opening when the switch is in its not-full condition.
6. An aircraft potable-water system as set forth in claim 5, wherein a float is movable between a lower location and an upper location, and wherein the float is in its upper location when the switch is in its full condition.
7. An aircraft potable-water system as set forth in claim 6, wherein the float is lifted by potable water within the storage tank to the upper location.
8. An aircraft potable-water system as set forth in claim 7, wherein the drain is a drainmast.
9. An aircraft potable-water system as set forth in claim 1, wherein an upstream end of the overflow line communicates with the ground-fill line andor the potable tank.
10. An aircraft potable-water system as set forth in claim 9, wherein the upstream end of the overflow line communicates with the ground-fill line.
11. An aircraft potable-water system as set forth in claim 1, wherein the valve is a pressure-activated valve that automatically closes upon the tank reaching a predetermined pressure.
12. An aircraft potable-water system as set forth in claim 1, wherein the valve is set so as to not open at cabin pressure when the aircraft is in flight.
13. An aircraft potable-water system as set forth in claim 12, wherein the drain is a drainmast.
14. An aircraft potable-water system as set forth in claim 1, wherein the valve is set to activate at a pressure greater than the pressure difference corresponding to the maximum expected altitude of the aircraft and the expected minimum cabin pressure.
15. An aircraft comprising a drainmast and a potable-water system as set forth in claim 1, wherein the downstream end of the overflow line is connected to the drainmast for ejection of tank-overflow water therethrough.
16. An aircraft as set forth in claim 15, comprising a water station for dispensing potable water during flight, wherein the potable-water system further comprises a water supply line extending from the storage tank to the water station (14).
17. A method of filling the storage tank of the aircraft set forth in claim 15 with potable water, said method comprising the steps of:
connecting the upstream end of the ground-fill line to an external potable-water source;
allowing potable water from the external source to flow through the ground-fill line to the storage tank; and
stopping the flow of potable water from the external source when potable water is ejected through the drainmast.
18. A method as set forth in claim 17, further comprising the step of disconnecting the upstream end of the ground-fill line from the external potable-water source.
19. A method as set forth in claim 17, characterized by the absence of non-automatic adjustment of an overflow-line-associated valve within the aircraft.
20. A method as set forth in claim 17, wherein said steps are performed while the aircraft is grounded.