RE: RE: RE: RE: processes rare earth 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.