Matrices containing lithium aluminates

Abstract

Provided is a particulate composition comprising a collection of resin beads and LiX.2Al(OH).sub.3.nH.sub.2O, wherein n is 0 to 10, wherein X is a halogen, wherein the resin beads contain polymer having 0.5 to 3 equivalents of amine pendant groups per liter of the particulate composition, wherein the resin beads have average pore diameter of 5 to 100 nm, wherein the collection of resin beads has harmonic mean particle diameter of 200-1000 micrometers; wherein the collection of resin beads has surface area of 20 to 150 m.sup.2/g; and wherein aluminum is present in an amount of 14.5% percent or higher, by weight of aluminum atoms based on the total weight of the particulate composition. Also provided is a method of removing lithium from brine using such a composition.

Claims

1. A method of making a particulate composition comprising depositing LiX.2Al(OH).sub.3.nH.sub.2O, wherein n is 0 to 10, wherein X is a halogen, in the pores of a preliminary particulate composition, wherein the preliminary particulate composition comprises a collection of preliminary resin beads, wherein the preliminary resin beads contain polymer having 0.5 to 3 equivalents of amine pendant groups per liter of the preliminary particulate composition, wherein the preliminary resin beads have average pore diameter of 5 to 15 nm, as measured by the BET method using nitrogen gas, wherein the collection of preliminary resin beads has harmonic mean particle diameter of 200-1000 micrometers; wherein the collection of preliminary resin beads has surface area of 20 to 150 m.sup.2/g.

Description

EXAMPLE 1

Procedure for Depositing Salt (a) onto Preliminary Resin Particles

(1) The procedure for depositing salt (a) onto preliminary resin particles was as follows. 1 liter of resin was covered with water to make total volume of 1200 mL. 200 mL of concentrated HCl was added; the mixture was stirred and allowed to stand overnight. Fluid was drained from the mixture using vacuum, and the resin was repeatedly rinsed with water. Resin was mixed with 1.5 L 30% AlCl.sub.3 solution and stirred. Resin was drained using vacuum. 1 L of aqueous 30% by weight ammonia solution was added to the resin and stirred, then drained using vacuum, followed by washing with water. 1 L of 0.1N ammonium chloride was added and stirred, and the pH was adjusted to 10.5 to 11 with aqueous 1N NaOH, followed by washing with water. 25 mL of 1N NaOH and water were added, to give total volume of 1.6 L. The mixture was allowed to stand for 16 to 24 hours and then the resin was washed with water. Then 2NaAlO.sub.2.NaOH was added in six lots of 167 g each. An aqueous solution of 36% HCl was added continuously. The resin was then washed with water. The resin was washed with 1.5 L aqueous 26% by weight solution of NaCl then stored in 2.2 L. Then 250 g LiCl was added; the mixture was stirred and then placed in an oven at 95° C. for 16 hours. At this point salt (a) was deposited onto the resin.

(2) Then aqueous 26% by weight NaCl was added to make total volume of 2.2 L. The mixture was heated to 70° C. and 60 g of NH.sub.4Cl was added. The resin was titrated with aqueous 36% HCl followed by 1N HCl to pH of 5.

(3) Three different preliminary resins were used. Their characteristics prior to deposition of salt (a) were as follows. PR-1C and PR-3C were comparative; PR-2 was an example. All three were vinyl aromatic polymers with pendant amine groups.

(4) TABLE-US-00001 TABLE 1 Properties of Preliminary Resins Pore Harmonic Mean Resin Diameter Surface Area Amine Groups Diameter Number (nm) (m.sup.2/g) (equ/L) (μm) PR-1C 38 37 1.2 200-500 PR-2 11 36 1.3 490-690 PR-3C 27 27 1.45 400-700

(5) The three preliminary resins were treated as above to deposit salt (a).

EXAMPLE 2

Adsorption of Lithium from Brine Using Resins Made by the Process of Example 1

(6) Each resin was exposed to brine. The brine was a water solution containing the following solutes: 0.32% by weight KCl; 0.82% by weight NaCl; 0.12% by weight CaSO.sub.4; 31.2% by weight MgCl.sub.2; and 1.58 g/L LiCl. The resin was exposed to brine using the following procedure. 30 ml of resin was loaded into a column with height of 180 mm. A level of 1 cm of deionized (DI) water was maintained over the surface of the resin. The column and the brine were heated to 40° C. Brine was loaded onto the top of the column and passed through the column at a rate of 6 BV/hr. Effluent was collected in samples of 2 BV each and analyzed for lithium content. After 50BV of brine passed through the column, the liquid was drained out of the column, leaving liquid level of 1 cm over the resin top surface.

(7) The brine as it exits the column is known as the effluent. The lithium content of effluent samples was analyzed by atomic absorption spectroscopy.

(8) The effectiveness of the treated resins at removal of lithium was assessed by measuring the lithium content of each sample of effluent. A lower concentration of lithium in the effluent demonstrates greater adsorption of lithium by the treated resin. The results were as follows.

(9) TABLE-US-00002 TABLE 2 Concentration of Lithium in Effluent (ppm by weight) BV PR-1C plus salt (a) PR-2 plus salt (a) PR-3C plus salt (a) 2 99 27 43 4 75 18 119 6 97 39 118 10 125 93 156 16 145 120 157 22 156 138 169 26 191 151 142 30 173 154 172 34 170 175 166 38 188 177 186 44 174 166 191
Up to 30 BV, the inventive resin (PR-2 plus salt (a)) showed superior ability to adsorb lithium. After 30 BV, all three of the resins approached saturation.

EXAMPLE 3

Adsorption/Desorption Cycles with Treated Resin PR-2 Loaded with Salt (a)

(10) After the adsorption process described in Example 2, the resin was subjected to a desorption process as follows:

(11) The resin in the column was cooled to room temperature, then rinsed with 2 BV of DI water at 12 BV/hr. The resin in the column was heated to 90° C. An aqueous solution of LiCl having 300 ppm by weight lithium was also heated to 90° C. The resin in the column was then rinsed with the aqueous LiCl solution at 1.5 BV/hr. Samples were collected every 0.2 BV and analyzed for lithium content. A “cycle” is a combination of an adsorption process as described in Example 2 followed by a desorption process.

(12) The PR-2 resin loaded with salt (a) was subjected to 29 cycles. In each cycle, the total amount of lithium adsorbed was over 4 g of lithium per liter of resin. The behavior during the desorption cycle is characterized by the desorption quotient, which is the quotient of the total amount of lithium desorbed during the desorption process divided by the total amount of lithium adsorbed during the adsorption process, expressed as a percentage. Over 13 cycles, the desorption quotients were as follows:

(13) TABLE-US-00003 TABLE 3 Desorption Quotients Cycle 1 Cycle 2 Cycle 3 Cycle 4 Cycle 5 Cycle 6 Cycle 7 65% 65% 85% 88% 108% 67% 63% Cycle 8 Cycle 9 Cycle 10 Cycle 11 Cycle 12 Cycle 13 77% 54% 149% 106% 72% 71%
the average desorption quotient was 82%. This consistent behavior during both adsorption and desorption over many cycles demonstrates that PR-2 loaded with salt (a) has the desired ability to maintain performance after multiple cycles.