RE: RE: International patent application WHAT IS CLAIMED IS:
1. A process for recovering at least one rare earth element from an aluminum-bearing material, said process comprising : leaching said aluminum-bearing material with an acid so as to obtain a leachate comprising at least one aluminum ion, at least one iron ion, said at least one rare earth element, and a solid, and separating said leachate from said solid; substantially selectively removing at least one of said at least one aluminum ion and said at least one iron ion from said leachate and optionally obtaining a precipitate; and substantially selectively removing said at least one rare earth element from said leachate and/or said precipitate.
2. A process for recovering at least one rare earth element from an aluminum-bearing material, said process comprising : leaching said aluminum-bearing material with an acid so as to obtain a leachate comprising at least one aluminum ion, at least one iron ion, and said at least one rare earth element, and a solid, and separating said leachate from said solid; and substantially selectively removing at least one member chosen from said at least one rare earth element, said at least one iron ion and said at least one aluminum ion from said leachate.
3. The process of claim 1 , wherein said process comprises : leaching said aluminum-bearing material with HCI so as to obtain said leachate comprising said at least one aluminum ion, said at least one iron ion, and said at least one rare earth element, and said solid and separating said leachate from said solid; substantially selectively removing said at least one aluminum ion from said leachate, thereby obtaining a composition comprising said at least one iron ion, and said at least one rare earth element; and substantially selectively at least partially removing said at least one iron ion from said composition, thereby obtaining a liquor comprising said at least one rare earth element.
4. The process of claim 3, wherein said at least one aluminum ion is substantially selectively removed from said leachate by substantially selectively precipitating it from said leachate and removing it therefrom by carrying out a solid-liquid separation.
5. The process of claim 3, wherein said at least one aluminum ion is substantially selectively removed from said leachate by substantially selectively precipitating it under the form of AICI3 and removing it therefrom by carrying out a solid-liquid separation.
6. The process of any one of claims 3 to 5, wherein said composition comprises HCI, said at least one iron ion, and said at least one rare earth element.
7. The process of any one of claims 3 to 5, wherein said composition is an acidic composition that comprises, said at least one iron ion, and said at least one rare earth element.
8. The process of any one of claims 3 to 7, wherein said at least one iron ion is substantially selectively removed from said composition by carrying out an hydrolysis so as to convert said at least one iron ion into Fe203 and removing said precipitated Fe203 from said composition by carrying out a solid-liquid separation, thereby obtaining said liquor comprising said at least one rare earth element.
9. The process of any one of claims 3 to 7, wherein said at least one iron ion is Fe3+ and is substantially selectively partially removed from said composition, and wherein said composition is further treated with a reducing agent so as to convert Fe3+ into Fe2+ and then, Fe2+, under the form of FeC , is removed from said composition by carrying out a solid-liquid separation, thereby obtaining said liquor comprising said at least one rare earth element.
10. The process of any one of claims 3 to 9, wherein said at least one rare earth element is substantially selectively precipitated, extracted and/or isolated from said liquor by means of a liquid-liquid extraction.
11. The process of any one of claims 3 to 10, wherein said at least one rare earth element is extracted from said liquor by means of liquid- liquid extraction.
12. The process of any one of claims 3 to 10, wherein said at least one rare earth element is recovered from said liquor by means of liquid- liquid extraction.
13. The process of any one of claims 10 to 12, wherein said liquid-liquid extraction is carried out using at least one of di-(2-ethylhexyl) phosphoric acid and mono(2-ethylhexyl)2-ethylhexyl phosphonate.
14. The process of any one of claims 10 to 12, wherein said liquid-liquid extraction is carried out using di-(2-ethylhexyl)phosphoric acid. The process of any one of claims 10 to 12, wherein said liquid-liquid extraction is carried out using bis(2,4,4- trimethylpentyl)monothiophosphinic acid).
The process of any one of claims 10 to 12, wherein said liquid-liquid extraction is carried out using an alkyl phosphate.
The process of any one of claims 10 to 12, wherein said liquid-liquid extraction is carried out using tri-butyl phosphate.
The process of any one of claims 10 to 12, wherein said liquid-liquid extraction is carried out using octyl phenyl phosphate.
The process of any one of claims 10 to 12, wherein said liquid-liquid extraction is carried out using 2-ethylhexylphosphonic acid mono-2- ethylhexyl ester and toluene.
The process of any one of claims 10 to 12, wherein said liquor comprises said at least one rare earth element under the form of a chloride, and wherein said liquor is reacted with an extracting agent in order to substantially selectively extract gallium therefrom, thereby obtaining a Ga-free solution and an extracted gallium solution, and separating said solutions from one another.
The process of claim 20, wherein said gallium is said liquor is under the form of GaC^.
The process of claim 20 or 21 , wherein said extracting agent is octyl phenyl phosphate or 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester and toluene.
The process of claim 20 or 21 , wherein said extracting agent is tri- butyl phosphate.
24. The process of any one of claims 20 to 23, wherein said extracted GaCI3 is then precipitated and then converted into Ga203.
25. The process of any one of claims 20 to 24, wherein the Ga-free solution is then reacted with another an extracting agent in order to substantially selectively extract cerium therefrom, thereby obtaining a Ce-free solution and an extracted cerium solution, and separating said solutions from one another.
26. The process of claim 25, wherein said cerium in said Ga-free solution is under the form of CeC .
27. The process of claim 25 or 26, wherein said another extracting agent is tri-butyl phosphate, di-isoamylmethyl phosphonate, di-(2-ethylhexyl) phosphoric acid, or 7-(4-ethyl-1-methyloctyl)-8-hydroxyquinoline.
28. The process of any one of claims 25 to 27, further comprising converting said extracted cerium into Ce02.
29. The process of any one of claims 25 to 28, further comprising reacting the Ce-free solution with a further extracting agent in order to substantially selectively extract scandium therefrom, thereby obtaining a Sc-free solution and an extracted scandium solution, and separating said solutions from one another.
30. The process of claim 29, wherein said scandium in said Ce-free solution is under the form of ScCI3.
31. The process of claim 29 or 30, wherein said further extracting agent is di-(2-ethylhexyl) phosphoric acid or di-(2-ethylhexyl) phosphinic acid.
32. The process of any one of claims 29 to 31 , further comprising converting said extracted scandium into Sc203. The process of claim 32, wherein said extracted scandium is converted into SC2O3 by means of NaOH.
The process of any one of claims 29 to 33, further comprising reacting the Sc-free solution with still a further extracting agent in order to substantially selectively extract samarium, europium or a mixture thereof, thereby obtaining a Sm-free solution and/or Eu-free solution and extracted samarium and/or europium solution, and separating said solutions from one another.
The process of claim 34, wherein said still a further extracting agent is chosen from bis(2,4,4-trimethylpentyl) phosphinic acid and di-(2- ethylhexyl) phosphoric acid.
The process of claim 34 or 35, further comprising reacting the Sm-free solution and/or Eu-free solution with still another extracting agent in order to substantially selectively extract gadolinium, thereby obtaining a Gd-free solution and an extracted gadolinium solution, and separating said solutions from one another.
The process of claim 36, wherein said still another extracting agent is 8-hydroxyquinoline.
The process of claim 36 or 37, further comprising reacting the Gd-free solution with yet another extracting agent in order to substantially selectively extract yttrium, thereby obtaining a Y-free solution and an extracted yttrium solution, and separating said solutions from one another.
The process of claim 38, wherein said yet another extracting agent is (2-ethylhexyl)phosphonic acid.
40. The process of claim 38, wherein said yet another extracting agent is di-(2-ethylhexyl)phosphonic acid.
41. The process any one of claims 38 to 40, further comprising reacting the Y-free solution with still yet another extracting agent in order to substantially selectively extract dysprosium and/or erbium, thereby obtaining a Dy-free solution and/or an Er-free solution and an extracted dysprosium and/or erbium solution, and separating said solutions from one another.
42. The process of any one of claims 3 to 9, wherein said liquor is reacted with a first extracting agent in order to substantially selectively extract gallium therefrom, thereby obtaining a Ga-free solution and an extracted gallium solution, and separating said solutions from one another.
43. The process of claim 42, wherein said gallium in said liquor is under the form of GaCI3.
44. The process of claim 42 or 43, wherein said first extracting agent is tri- butyl phosphate.
45. The process of claim 42 or 43, wherein said first extracting agent is tri- butyl phosphate in kerosene.
46. The process of any one of claims 42 to 45, wherein said Ga-free solution is reacted with a precipitating agent for precipitating at least one rare earth element present in said Ga-free solution, thereby obtaining a precipitate containing said at least one rare earth element and recovering said precipitate via a solid-liquid separation.
47. The process of claim 46, further comprising leaching said precipitate with an acid so as to obtain a leach solution comprising said at least one rare earth element.
48. The process of claim 47, wherein said acid is HCI.
49. The process of any one of claims 46 to 48, wherein said leach solution is reacted with a second extracting agent so as to substantially selectively extract a first group of rare earth elements, thereby obtaining a solution comprising said extracted rare earth elements of said first group and a rafinate comprising a second group of rare earth elements, and separating said solution from said rafinate.
50. The process of claim 49, wherein said first group comprises yttrium and scandium.
51. The process of claim 49 or 50, wherein said second group comprises cerium, neodynium, europium and praseodymium.
52. The process of any one of claims 49 to 51 , wherein said second extracting agent is chosen from di-(2-ethylhexyl)phosphoric acid and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester.
53. The process of any one of claims 49 to 52, further comprising reacting said solution comprising said extracted rare earth elements of said first group with HCI at least once so as to remove impurities therefrom.
54. The process of any one of claims 49 to 53, further comprising stripping said solution comprising said extracted rare earth elements of said first group with an acid so as to obtain a first group strip liquor.
55. The process of claim 54, wherein said acid is HCI.
56. The process of claim 54 or 55, further comprising repeating at least once said extraction with said second extracting agent.
57. The process of claim 54, 55 or 56, wherein said first group strip liquor is reacted with a third extracting agent so as to substantially selectively extracting at least one of scandium, erbium and dysprosium from said first group strip liquor, thereby obtaining a solution comprising said extracted at least one of scandium, erbium and dysprosium, and an yttrium raffinate, and separating said solution from said raffinate.
58. The process of claim 57, wherein said third extracting agent is tri-butyl phosphate.
59. The process of claim 57 or 58, further comprising stripping said solution comprising said extracted at least one of scandium, erbium and dysprosium solution with an acid so as to obtain another first group strip liquor.
60. The process of claim 59, wherein said acid is HCI.
61. The process of claim 59 or 60, wherein said another first group strip liquor is reacted with a fourth extracting agent so as to substantially selectively extracting erbium and dysprosium from said another first group strip liquor, thereby obtaining a solution comprising said extracted erbium and dysprosium, and a scandium raffinate, and separating said solution from said raffinate.
62. The process of claim 56 or 57, wherein said another first group strip liquor is reacted with a fourth extracting agent so as to substantially selectively extracting scandium from said another first group strip liquor, thereby obtaining a solution comprising said extracted scandium, and raffinate comprising erbium dand dysprosium, and separating said solution from said raffinate.
63. The process of any one of claims 3 to 12, wherein said at least one rare earth element is substantially selectively precipitated, extracted and/or isolated by means of an adsorption on activated charcoal optionally modified with tributyl phosphate or on a polyurethane polyether foam (PUF).
64. The process of claim 1 or 2, wherein said at least one rare earth element is substantially selectively removed by means of a liquid- liquid extraction.
65. The process of claim 64, wherein said liquid-liquid extraction is carried out by using an extracting agent.
66. The process of claim 65, wherein said extracting agent is chosen from di-(2-ethylhexyl) phosphoric acid, mono(2-ethylhexyl)2-ethylhexyl phosphonate, bis(2,4,4-trimethylpentyl)monothiophosphinic acid), octyl phenyl phosphate (OPAP), 2-ethylhexylphosphonic acid mono-2- ethylhexyl ester, tributyl phosphate, di-isoamylmethyl phosphonate, 7- (4-ethyl-1-methyloctyl)-8-hydroxyquinoline, di-(2-ethylhexyl) phosphinic acid, bis(2,4,4-trimethylpentyl) phosphinic acid, 8- hydroxyquinoline, and (2-ethylhexyl)phosphonic acid.
67. The process of claim 65, wherein said extracting agent is chosen from diethylenetriamine-penthaacetic acid, ethylenediaminetetraacetic, 1 ,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid, and bis(2,4,4-trimethylpentyl)monothiophosphinic acid.
68. The process of claim 64 to 67, wherein said at least one rare earth element is chosen from scandium, gallium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, dysprosium, erbium, and ytterbium.
69. The process of claim 64 to 67, wherein said at least one rare earth element is chosen from scandium, gallium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium and dysprosium.
70. The process of claim 64 to 67, wherein said at least one rare earth element is chosen from scandium, gallium, yttrium and cerium.
71. The process of claim 64 to 67, wherein said at least one rare earth element is chosen from scandium, gallium and yttrium.
72. The process of claim 2, wherein said process comprises selectively precipitating at least two members chosen from said at least one rare earth element that is in the form of ions, said at least one iron ion and said at least one iron ion aluminum ion.
73. The process of claim 72, wherein each of said members is precipitated separately.
74. The process of claim 72, wherein said at least two members are precipitated together.
75. The process of any one of claims 1 to 12, wherein said at least one rare element is chosen from scandium, gallium, yttrium and cerium.
76. The process of any one of claims 1 to 12, wherein said at least one rare element is cerium.
77. The process of any one of claims 1 to 12, wherein said at least one rare element is gallium.
78. The process of any one of claims 1 to 10, wherein said at least one rare element is scandium.
79. The process of claim 78, wherein said scandium is precipitated in the form of Sc(OH)3, ScCI3, ScF3, and/or [ScF6]3' or hydrates thereof.
80. The process of claim 78, wherein said scandium is precipitated in the form of Sc(OH)3 or hydrates thereof.
8 . The process of claim 79 or 80, wherein said scandium is precipitated at a pH of about 7 to about 9.
82. The process of claim 79 or 80, wherein said scandium is precipitated at a pH of about 7 to about 8.
83. The process of claim 1 , wherein said process comprises leaching said aluminum-bearing material with HCI so as to obtain said leachate comprising said at least one aluminum ion, said at least one iron ion, and said at least one rare earth element, and said solid and separating said leachate from said solid; substantially selectively removing said at least one iron ion from said leachate, thereby obtaining a composition comprising said at least one aluminum ion, and said at least one rare earth element; and substantially selectively at least partially removing said at least one aluminum ion from said composition, thereby obtaining a liquor comprising said at least one rare earth element.
84. The process of any one of claims 1 to 12, wherein said process comprises leaching said aluminum-bearing material with HCI so as to obtain said leachate comprising said at least one aluminum ion, said at least one iron ion, and said at least one rare earth element, and said solid and separating said leachate from said solid; substantially selectively removing said at least one iron ion from said leachate, thereby obtaining a composition comprising said at least one aluminum ion, and said at least one rare earth element; and substantially selectively at least partially removing said at least one aluminum ion from said composition, thereby obtaining a liquor comprising said at least one rare earth element.
85. The process of claim 83 or 84, wherein said at least one iron ion is substantially selectively precipitated in basic conditions in which the pH is of at least 10.
86. The process of claim 85, wherein said pH is at least 11.
87. The process of claim 85, wherein said pH is at least 12.
88. The process of claim 85, wherein said pH is about 10.8 to about 1 .2.
89. The process of claim 85, wherein said pH is about 11.5 to about 12.5.
90. The process of claim 85, wherein said pH is comprised between 11 and 12.
91. The process of claim 83 or 84, wherein at least a portion of said iron ions is precipitated at a pH of about 3 to about 4.
92. The process of claim 83 or 84, wherein at least a portion of said iron ions is precipitated at a pH of about 3.0 to about 3.5.
93. The process of claim 83 or 84, wherein at least a portion of said iron ions is precipitated at a pH of about 3.5 to about 4.0.
94. The process of claim 83 or 84, wherein at least a portion of said iron ions is precipitated at a pH of about 5 to about 6.
95. The process of claim 83 or 84, wherein at least a portion of said iron ions is precipitated at a pH of about 5.0 to about 5.5.
96. The process of claim 83 or 84, wherein said leaching is carried out at a pH of about 0.5 to about 2.5., then said at least one iron is precipitated at a pH of at least about 9.5, then said at least one aluminum ion is precipitated at a pH of about 8 to about 9, and then at least one scandium ion is precipitated at a pH of about 7 to about 8.
97. The process of claim 83 or 84, wherein said leaching is carried out at a pH of about 0.5 to about 1.5., then said at least one iron is precipitated at a pH of at least about 10.5, then said at least one aluminum ion is precipitated at a pH of about 8 to about 9, and then at least one scandium ion is precipitated at a pH of about 7 to about 8.
98. The process of claim 83 or 84, wherein said leaching is carried out at a pH of about 0.5 to about 1.5., then said at least one iron is precipitated at a pH of at least about 11, then said at least one aluminum ion is precipitated at a pH of about 8 to about 9, and then at least one scandium ion is precipitated at a pH of about 7 to about 8.
99. The process of any one of claims 78 to 82 and 96 to 98, wherein said scandium is precipitated from a by-product generated during said process.
100. The process of any one of claims 78 to 82 and 96 to 98, wherein said scandium is precipitated from a solution generated during said process.
101. The process of claim 100, wherein said scandium is precipitated using HN03.
102. The process of claim 1 or 2, wherein said at least one rare earth element is substantially selectively precipitated, extracted and/or isolated by at least one technique chosen from ion exchange resin, extraction by means of solvent(s) and adsorption.
103. The process of claim 1 or 2, wherein said at least one rare earth element is substantially selectively precipitated, extracted and/or isolated by means of an ion exchange resin.
104. The process of claim 1 or 2, wherein said at least one rare earth element is substantially selectively precipitated, extracted and/or isolated by means of a liquid-liquid extraction.
105. The process of claim 1 or 2, wherein said at least one rare earth element is substantially selectively precipitated, extracted and/or isolated by means of an electrowinning process.
106. The process of claim 83 or 84, wherein said leaching is carried out at a pH of about 0.5 to about 2.5., then said at least one iron is precipitated at a pH of at least about 9.5, then said at least one aluminum ion is precipitated at a pH of about 8 to about 9, and then and then said at least one rare earth element is substantially selectively extracted.
107. The process of claim 83 or 84, wherein said leaching is carried out at a pH of about 0.5 to about 1.5., then said at least one iron is precipitated at a pH of at least about 10.5, then said at least one aluminum ion is precipitated at a pH of about 8 to about 9, and then said at least one rare earth element is substantially selectively extracted.
108. The process of claim 83 or 84, wherein said leaching is carried out at a pH of about 0.5 to about 1.5., then said at least one iron is precipitated at a pH of at least about 11 , then said at least one aluminum ion is precipitated at a pH of about 8 to about 9, and then said at least one rare earth element is substantially selectively extracted.
109. The process of any one of claims 1 to 108, wherein said leaching is carried out with HCI under a pressure of about 5 KPag to about 850 KPag.
110. The process of any one of claims 1 to 108, wherein said leaching is carried out with HCI under a pressure of about 50 KPag to about 800 KPag.
111. The process of any one of claims 1 to 108, wherein said leaching is carried out with HCI under a pressure of about 100 KPag to about 750 KPag.
112. The process of any one of claims 1 to 108, wherein said leaching is carried out with HCI under a pressure of about 150 KPag to about 700 KPag.
113. The process of any one of claims 1 to 108, wherein said leaching is carried out with HCI under a pressure of about 200 KPag to about 600 KPag.
114. The process of any one of claims 1 to 108, wherein said leaching is carried out with HCI under a pressure of about 250 KPag to about 500 KPag.
115. The process of any one of claims 1 to 108, wherein said aluminum- bearing material is leached with HCI at a temperature of at least 80 °C.
116. The process of any one of claims 1 to 108, wherein said aluminum- bearing material is leached with HCI at a temperature of at least 90 °C.
117. The process of any one of claims 1 to 108, wherein said aluminum- bearing material is leached with HCI at a temperature of at least 120 °C.
118. The process of any one of claims 1 to 108, wherein said aluminum- bearing material is leached with HCI at a temperature of at least 140 °C.
119. The process of any one of claims 1 to 108, wherein said aluminum- bearing material is leached with HCI at a temperature of about 100 °C to about 110 °C.
120. The process of any one of claims 1 to 108, wherein said aluminum- bearing material is leached with HCI at a temperature of about 140 °C to about 175 °C.
121. The process of any one of claims 1 to 120, wherein said acid is HCI having a concentration of about 6 M.
122. The process of any one of claims 1 to 120, wherein said acid is HCI having a concentration of about 18 to about 32 wt%.
123. The process of any one of claims 1 to 122, wherein the aluminum- bearing material / acid ratio is about 1 / 10 in weight by volume.
124. The process of claim 1 or 2, further comprising at least one of at least partially removing said at least one iron ion from said leachate by substantially complexing said at least one iron ion with an extracting agent; selectively precipitating said at least one iron ion; selectively precipitating said at least one aluminum ion; and at least partially removing said at least one aluminum ion from said leachate by substantially complexing said at least one aluminum ion with another extracting agent.
125. The process of claim 1 or 2, wherein said process comprises: leaching said aluminum-bearing material with HCI so as to obtain a leachate and a solid residue, and separating said leachate from said solid residue; at least partially removing said at least one iron ion from said leachate by substantially selectively precipitating said at least one iron ion by reacting said leachate with a base so as to obtain an Al-rich aqueous composition comprising said at least one rare element and a precipitate, and removing said precipitate from said composition; purifying said Al-rich aqueous composition by substantially selectively precipitating said at least one aluminum ion, thereby obtaining another composition comprising said at least one rare element and another precipitate, removing said precipitate from said composition; and substantially selectively extracting said at least one rare element from said another composition.
126. The process of claim 1 or 2, wherein said process comprises: leaching said aluminum-bearing material with HCI so as to obtain a leachate and a solid residue, and separating said leachate from said solid residue, at least partially removing said at least one iron ion from said leachate by substantially selectively precipitating said at least one iron ion by reacting said leachate with a base so as to obtain an Al-rich aqueous composition comprising said at least one rare element and a precipitate, and removing said precipitate from said composition; substantially selectively extracting said at least one aluminum ion from said Al-rich aqueous composition by means of a hollow fiber membrane, or by a liquid-liquid extraction, and removing said extracted at least one aluminum ion, thereby obtaining an Al- depleted aqueous composition comprising said at least one rare element; and substantially selectively extracting said at least one rare element from said Al-depleted aqueous composition.
127. The process of claim 1 or 2, wherein said process comprises: leaching said aluminum-bearing material with HCI so as to obtain a leachate and a solid residue, and separating said leachate from said solid residue; at least partially removing said at least one iron ion from said leachate by substantially selectively complexing said at least one iron ion with an extracting agent so as to obtain an Al-rich aqueous composition comprising said at least one rare earth element; purifying said Al-rich aqueous composition by substantially selectively precipitating said at least one aluminum ion, thereby obtaining another composition comprising said at least one rare element and another precipitate, removing said precipitate from said composition; and substantially selectively extracting said at least one rare element from said another composition. The process of claim 1 or 2, wherein said process comprises: leaching said aluminum-bearing material with HCI so as to obtain a leachate and a solid residue, and separating said leachate from said solid residue; at least partially removing said at least one iron ion from said leachate by substantially selectively complexing said at least one iron ion with an extracting agent so as to obtain an Al-rich aqueous composition comprising said at least one rare earth element; substantially selectively extracting said at least one aluminum ion from said Al-rich aqueous composition by means of a hollow fiber membrane, or by a liquid-liquid extraction, and removing said extracted at least one aluminum ion, thereby obtaining an Al- depleted aqueous composition comprising said at least one rare element; and substantially selectively extracting said at least one rare element from said Al-depleted aqueous composition.
129. The process of claim 1 or 2, wherein said process comprises: leaching said aluminum-bearing material with HCI so as to obtain a leachate and a solid residue, and separating said leachate from said solid residue; at least partially removing said at least one aluminum ion from said leachate by substantially selectively precipitating said at least one aluminum so as to obtain an iron-rich aqueous composition comprising said at least one rare element and a precipitate, and removing said precipitate from said composition; substantially selectively precipitating said at least one iron ion from said iron-rich aqueous composition, and removing said precipitate therefrom, thereby obtaining thereby obtaining an iron- depleted aqueous composition comprising said at least one rare element; and substantially selectively extracting said at least one rare element from said iron-depleted aqueous composition.
130. The process of claim 129, wherein said at least one aluminum ion is precipitated under the form of AICI3 in a crystallizer by sparging gaseous HCI.
131. The process of claim 129, wherein said at least one iron ion is precipitated under the form of Fe203 by means of an hydrolysis.
132. The process of claim 125, wherein said Al-rich aqueous composition is purified by complexing said at least one aluminum ion with an extracting agent so as to obtain a complex, separating said complex form said composition and precipitating said at least one aluminum ion.
133. The process of claim 132, wherein said extracting agent is bis(2,4,4- trimethylpentyl) phosphinic acid.
134. The process of claim 126 or 127, wherein an Al-rich aqueous composition is purified by complexing impurities contained in said Al- rich aqueous composition with an extracting agent, at least partially removing said complexed impurities from said composition and precipitating said aluminum ions.
135. The process of claim 134, wherein said extracting agent is chosen from di-2-ethylhexyl phosphoric acid (HDEHP), bis(2,4,4- trimethylpentyl) phosphinic acid and 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester.
136. The process of claim 1 or 2, wherein said leaching is carried out with an acid chosen from HCI, H2S04, HN03 and mixtures thereof.
137. The process of claim 8, wherein after said removal of said precipitated Fe203, said liquor containing said at least one rare earth element is recirculated back for being further concentrated by being used in precipitating the at least one aluminum.
138. The process of claim 8, wherein after said removal of said precipitated Fe203, said liquor containing said at least one rare earth element is recirculated back for being further concentrated by being used in precipitating the at least one aluminum ion under the form of AICI3.
139. The process of any one of claims 1 to 8, 83 to 89, 97 to 99, 106 to 108, 125, 126, 137 and 138 wherein said at least one iron ion is precipitated under the form of Fe(OH)3, Fe(OH)2, geotite, hematite and jarosite, hydrates thereof or mixtures thereof.
140. The process of any one of claims 83 to 89, 97 to 99, 106 to 108, 125 and 127, wherein said aluminum ions are precipitated under the form of AI(OH)3 or hydrates thereof.
141. The process of any one of claims 1 to 140, wherein said aluminum- bearing material is chosen from clays.
142. The process of any one of claims 1 to 140, wherein said aluminum- bearing material is chosen from argillite, mudstone, beryl, cryolite, garnet, spinel, bauxite and mixtures thereof.
143. The process of any one of claims 1 to 140, wherein said aluminum- bearing material is argillite.