The SuperLig~R 240 and SuperLig~R 83 systems were both shown to be capable of performing the Bi separation from the HCI matrix Kennecott solution. Both the SuperLig~R 240 and 83 pilot scale column systems showed the following: high Bi recovery (<1 g/liter Bi in the low Bi raffinate); high Bi purity in the Bi solid products (97 - 99 percent Bi metallic purity for the SuperLig~R 240 system and 99.9 - 99.99 percent Bi metallic purity for the SuperLig~R 83 system); no detectable loss in SuperLig~R bismuth binding capacity over the life of the pilot tests; and, optimized input volumes, including wash and elution recycles (where applicable) and volumes of washes and eluent. The required feed adjustments for the SuperLig~R 240 process were: (a) an ORP adjustment with bleach (hydrogen peroxide could also possibly be used) and (b) filtration. The required feed adjustments for the SuperLig~R 83 process were: (a) filtration and (b) 2 parts 1 M sulfuric acid to 1 part feed dilution. The SuperLig~R 240 pilot system using 0.55 kg dry resin gave a Bi concentrate of approximately 8.5 g/liter in a 60 C 1 M sulfuric acid elution with some of the 2 M HCI wash also added in. The SuperLig~R 240 system has a high tolerance for temperature variation. The Bi solid product was collected at virtually 100 percent first pass recovery in the precipitation/filtration by base neutralization with a predominantly BiOCI or Bi(OH)_3 solid product if the pH of the neutralization was controlled around pH 2 vs. a predominantly Bi(OH)_3 product if the pH was allowed to go significantly higher. Purity of this solid was 98 percent with Pb as the primary impurity. The overall dilution factor (feed solution compared to low Bi raffinate solution) was 1.7. During the Bi product recovery step, a secondary output stream of NaCI/Na_2SO_4 is produced. Also, during this step, a base for the precipitation is required. Ten cycles of the SuperLig~R 240 process were performed using the same SuperLig~R and column with a sustainable initial Bi capacity of 1.2 mole Bi/kg dry SuperLig~R 240. The SuperLig~R 83 pilot system using 0.9 kg dry SuperLig~R gave a Bi concentrate of 13-16 g/liter Bi. The 9 molar sulfuric acid elution temperature was 65+-3 C . The Bi solid product was collected down to approximately 1 g/liter Bi remaining in the solution by allowing the Bi concentrated product solution to come to equilibrium at room temperature. The metallic purity of this solid was 99.9 - 99.99 percent. The overall dilution factor (feed solution compared to low Bi raffinate solution) was 6. No other secondary streams other than a bleed off of the continually recycled 9 M sulfuric acid stream are required. Thirty six cycles of the SuperLig~R 83 process were completed with a Bi capacity of 0.2 mole Bi/kg dry SuperLig~R 83.
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