1. A continuous process for directly preparing high purity lithium carbonate from lithium containing brines comprising:
preparing a brine containing about 6.0 wt % lithium and further containing other ions such as sodium, magnesium, calcium, and sulfates naturally occurring in brines;
adding mother liquor containing carbonate from a prior precipitation step to precipitate magnesium as magnesium carbonate;
adding a solution of CaO and sodium carbonate to remove calcium and residual magnesium;
precipitating lithium carbonate from the purified brine by adding soda ash solution;
filtering the resultant solution to obtain solid lithium carbonate;
preparing an aqueous slurry of the lithium carbonate in a reactor equipped with an inlet for introducing carbon dioxide gas into said aqueous slurry to form an aqueous lithium bicarbonate solution, the reactor being at a temperature from at least minus 10 to 40 C.;
passing said aqueous lithium bicarbonate solution through a filter to clarify the solution and optionally an ion exchange column for further calcium and magnesium removal;
introducing said filtered lithium bicarbonate solution into a second reactor and adjusting the temperature of the solution to from 60-100 C. to precipitate ultra-pure lithium carbonate with sodium less than 0.0002 wt %, calcium less than 0.00007 wt % and magnesium less than 0.00001 wt %.
2. A continuous process for directly preparing high purity lithium carbonate from lithium containing brines comprising:
preparing a brine containing about 6.0 wt % lithium and further containing other ions such as sodium, magnesium, calcium, and sulfates naturally occurring in brines;
adding CaO to remove magnesium;
adding mother liquor containing carbonate from a prior precipitation step and soda ash solution to precipitate calcium carbonate;
filtering to remove calcium carbonate and to yield a purified lithium containing brine;
adding soda ash to said purified brine to precipitate lithium carbonate;
filtering the solution to recover the precipitated lithium carbonate,
preparing an aqueous lithium carbonate slurry in a reactor where such reactor is equipped with an inlet for introducing carbon dioxide gas into the lithium carbonate slurry to produce an aqueous lithium bicarbonate solution, wherein the reactor is at a temperature from at least minus 10to40 C.;
passing the aqueous lithium bicarbonate solution through a clarifying filter and optionally an ion exchange column for further calcium and magnesium removal;
introducing the filtered solution into a second reactor and adjusting the temperature of the solution to from 60-100 C. to precipitate the ultra-pure lithium carbonate with sodium less than 0.0002 wt %, calcium less than 0.00007 wt % and magnesium less than 0.00001 wt %.
3. The process of claim 1 wherein the lithium bicarbonate is only passed through a filter and proceeding to the second reactor at 60-100 C. to precipitate low sodium lithium carbonate with a sodium content of less than 0.0002 wt %.
4. The method of claim 1, wherein the carbon dioxide absorption reactor is from minus 10 C. but not more than 40 C., and preferably from 0-35 C., and the temperature of the reactor for precipitating high purity lithium carbonate is from 60-100 C., preferably 70-95 C.
5. The method of claim 1, wherein said ion exchange column comprises Amberlite IRC-718 as a cation exchange resin.
6. The process of claim 2 wherein the lithium bicarbonate is only passed through a filter and proceeding to the second reactor at 60-100 C. to precipitate low sodium lithium carbonate with a sodium content of less than 0.0002 wt %.
7. The method of claim 2, wherein the carbon dioxide absorption reactor is from minus 10 C. but not more than 40 C., and preferably from 0-35 C., and the temperature of the reactor for precipitating high purity lithium carbonate is from 60-100 C., preferably 70-95 C.
8. The method of claim 2, wherein the method is conducted at less than or equal to atmospheric pressure.
9. The method of claim 2, wherein said ion exchange column comprises Amberlite IRC-718 as a cation exchange resin.
10. High purity lithium carbonate, comprising less than 20 ppm sodium as an impurity.
11. High purity lithium carbonate, comprising less than 2 ppm sodium as an impurity.
12. Purified lithium carbonate comprising:
11
High Purity Low Sodium
Wt %
Li2CO3
Li2CO3
>99.4
Mg
<0.0007
Na
<0.0010
K
<0.00025
Ca
<0.0120
B
<0.0001
Al
<0.0002
As
<0.0001
Fe
<0.0001
Si
<0.0010
Zn
<0.00005
SO4
<0.037
Cl
<0.005
13. Purified lithium carbonate comprising:
12
Wt %
Ultra-High Purity Li2CO3
Li2CO3
>99.995
Mg
<0.00001
Na
<0.0002
K
<0.00015
Ca
<0.00007
B
<0.0001
Al
<0.0002
As
<0.0001
Fe
<0.0001
Si
<0.00011
Zn
<0.000014
SO4
<0.0030
Cl
<0.005
14. A continuous process for preparing high purity lithium chloride comprising:
reacting the lithium carbonate having a sodium content of less than 0.0002 wt % with hydrochloric acid having less than 1 ppm sodium to produce high purity lithium chloride having sodium content of less than 0.001 wt %.
15. High purity lithium chloride containing less than 20 ppm sodium.
16. The high purity lithium chloride of claim 15 containing less than 8 ppm sodium.
17. An apparatus for continuously purifying lithium carbonate comprising:
a dissolver which is a baffled reactor to dissolve lithium carbonate that includes a mixerdisperser,
a carbon dioxide gas dispersion tube,
a wash water filtratemother liquor filtrate recycle line,
a cooler,
a stilling well to separate gas and undissolved lithium carbonate solids from the resultant lithium bicarbonate solution, and
a continuous chemical grade lithium carbonate crystal feeder;
an inline filter to remove insoluble impurities from the lithium bicarbonate solution coming from the stilling well;
a heat exchanger to recover heat from the hot mother liquor that is recycled to the dissolver;
a heated gas scaled crystallizer with mixer to decompose the lithium bicarbonate solution to form low sodium lithium carbonate crystals, carbon dioxide gas, and mother liquor;
a slurry valve to remove the low sodium lithium carbonate crystals and mother liquor from the gas sealed crystallizer;
a gas line to continuously return the carbon dioxide produced in the crystallizer to the dissolver;
a separator such as a continuous belt filter to separate the low sodium lithium carbonate from the mother liquor and a wash water section to wash the lithium carbonate crystals;
a pump and line to return the mother liquor and wash filtrate to the dissolver;
a mother liquor bleed to control the sodium level and to maintain a constant liquid volume;
a carbon dioxide make up source.
18. The apparatus of claim 17, comprising a reactor using absorption columns, such as a sieve tray or a Scheibel column, to facilitate absorption of carbon dioxide.
19. A method for purifying metal carbonates that are insoluble in water but have corresponding metal bicarbonate salts that are more than 75% by wt. soluble in water by preparing an aqueous slurry of said metal carbonate;
introducing carbon dioxide gas into said aqueous slurry to form a corresponding metal bicarbonate solution; and
heating the metal bicarbonate solution to form a purified metal carbonate, wherein the heating is such that the temperature of the solution is raised to a temperature at which the metal carbonate is insoluble to precipitate the purified metal carbonate.
20. The method of claim 19, wherein said metal is lithium.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. A recombinant adeno-associated virus (rAAV) vector for obtaining factor VIII activity comprising in operable linkage:
(a) promoter;
(b) a polynucleotide encoding a polypeptide with factor VIII activity; and
(c) a polyadenylation site; wherein said polypeptide comprises factor VIII 90 kD heavy chain and light chain and wherein said (a), (b) and (c) are flanked by inverted terminal repeats.
2. The vector of claim 1, wherein said promoter is tissue specific.
3. The vector of claim 2, wherein said tissue is liver.
4. The vector of claim 3, wherein said promoter is the human factor IX promoter.
5. The vector of claim 1, wherein said promoter is obtained from a virus.
6. The vector of claim 5, wherein said virus is an oncogenic virus.
7. The vector of claim 6, wherein said virus is Rous sarcoma virus.
8. The vector of claim 1, comprising modification of the initiation codon of said polynucleotide to enhance expression of said polypeptide.
9. The vector of claim 1, wherein said heavy chain consists of two A domains of factor VIII and said light chain consists of an A domain and two C domains of factor VIII.
10. The vector of claim 1, further comprising between said promoter (a) and said polynucleotide (b) a splice donorsplice acceptor.
11. The vector of claim 10, wherein said splice donorsplice acceptor is obtained from human -globin.
12. The vector of claim 1, further comprising between said promoter (a) and said polynucleotide (b), the untranslated region of cytomegalovirus.
13. The vector of claim 1, which is pAAV-RSV-hFVIII.
14. The vector of claim 1, which is pAAV-RSV-U-hFVIII.
15. The vector of claim 1, which is pAAV-FIX-hFVIII.
16. The vector of claim 1, which is pAAV-FIX-U-hFVIII.
17. A virus particle containing the vector of claim 1.