==== Uranium chemistry in groundwater ==== TITLE Seawater SOLUTION_MASTER_SPECIES U U+4 0.0 238.0290 238.0290 U(4) U+4 0.0 238.0290 U(5) UO2+ 0.0 238.0290 U(6) UO2+2 0.0 238.0290 SOLUTION_SPECIES #primary master species for U #is also secondary master species for U(4) U+4 = U+4 log_k 0.0 U+4 + 4 H2O = U(OH)4 + 4 H+ log_k -8.538 delta_h 24.760 kcal U+4 + 5 H2O = U(OH)5- + 5 H+ log_k -13.147 delta_h 27.580 kcal #secondary master species for U(5) U+4 + 2 H2O = UO2+ + 4 H+ + e- log_k -6.432 delta_h 31.130 kcal #secondary master species for U(6) U+4 + 2 H2O = UO2+2 + 4 H+ + 2 e- log_k -9.217 delta_h 34.430 kcal UO2+2 + H2O = UO2OH+ + H+ log_k -5.782 delta_h 11.015 kcal 2UO2+2 + 2H2O = (UO2)2(OH)2+2 + 2H+ log_k -5.626 delta_h -36.04 kcal 3UO2+2 + 5H2O = (UO2)3(OH)5+ + 5H+ log_k -15.641 delta_h -44.27 kcal UO2+2 + CO3-2 = UO2CO3 log_k 10.064 delta_h 0.84 kcal UO2+2 + 2CO3-2 = UO2(CO3)2-2 log_k 16.977 delta_h 3.48 kcal UO2+2 + 3CO3-2 = UO2(CO3)3-4 log_k 21.397 delta_h -8.78 kcal PHASES Uraninite UO2 + 4 H+ = U+4 + 2 H2O log_k -3.490 delta_h -18.630 kcal Carnotite K2(UO2)2(VO4)2 = 2K+ + 2UO2+2 + 2VO4-3 log_k -56.730 delta_h 55 kcal Autunite Ca(UO2)2(PO4)2 = Ca+2 + 2UO2+2 + 2PO4-3 log_k -48.360 delta_h 0.0 SOLUTION 1 units ppm pH 8.22 pe 8.451 temp 25.0 redox N(5)/N(-3) pH 6.5 S(6) 3.3 as SO4 N(5) 0.58 as NO3 P(5) 0.1 U 0.01 V 0.01 Cl 0.22 Na 0.38 K 0.36 Ca 0.20 Mg 0.30 Alkalinity 0.68 as HCO3 N(-3) 0.81 as NH4 SAVE solution 1 SELECTED_OUTPUT -file ex21.txt -step true -pH true -pe true -reaction true -temperature true -alkalinity true -si CO2(g) CH4(g) N2(g) NH3(g) -gases CO2(g) N2(g) NH3(g) -totals Ca Na Cl S(6) N(5) Na K -molalities Ca+2 Na+ Cl- END TITLE Soil Processes USE solution 1 EQUILIBRIUM_PHASES 1 Autunite 0.0 Carnotite 0.0 Hydroxylapatite 0.0 Fluorite 0.0 SAVE solution 1 SELECTED_OUTPUT -file ex22.txt -step true -pH true -pe true -reaction true -temperature true -alkalinity true -si CO2(g) CH4(g) N2(g) NH3(g) -gases CO2(g) N2(g) NH3(g) -totals Ca Na Cl S(6) N(5) Na K -molalities Ca+2 Na+ Cl- END TITLE Evaporate water from soil REACTION 1 H2O -1.0 50.5 moles in 10 steps REACTION_Temperature 1 25 USE solution 1 SAVE solution 1 SELECTED_OUTPUT -file ex23.txt -step true -pH true -pe true -reaction true -temperature true -alkalinity true -si CO2(g) CH4(g) N2(g) NH3(g) -gases CO2(g) N2(g) NH3(g) -totals Ca Na Cl S(6) N(5) Na K -molalities Ca+2 Na+ Cl- END TITLE Vary temperature REACTION_TEMPERATURE 2 10.0 25.0 in 160 steps USE solution 1 SAVE solution 1 SELECTED_OUTPUT -file ex24.txt -step true -pH true -pe true -reaction true -temperature true -alkalinity true -si CO2(g) CH4(g) N2(g) NH3(g) -gases CO2(g) N2(g) NH3(g) -totals Ca Na Cl S(6) N(5) Na K -molalities Ca+2 Na+ Cl- END TITLE SURFACE_SPECIES Hfo_sOH + H+ = Hfo_sOH2+ log_k 7.18 Hfo_sOH = Hfo_sO- + H+ log_k -8.82 Hfo_sOH + Zn+2 = Hfo_sOZn+ + H+ log_k 0.66 Hfo_wOH + H+ = Hfo_wOH2+ log_k 7.18 Hfo_wOH = Hfo_wO- + H+ log_k -8.82 Hfo_wOH + Zn+2 = Hfo_wOZn+ + H+ log_k -2.32 USE solution 1 SURFACE 1 Hfo_sOH 5e-6 600. 0.09 Hfo_wOH 2e-4 SAVE solution 1 SELECTED_OUTPUT -file ex25.txt -step true -pH true -pe true -reaction true -temperature true -alkalinity true -si CO2(g) CH4(g) N2(g) NH3(g) -gases CO2(g) N2(g) NH3(g) -totals Ca Na Cl S(6) N(5) Na K -molalities Ca+2 Na+ Cl- END TITLE Redox Reaction USE solution 1 REACTION 1 CH2O 0.1 # add 0.1 mol CH2O; 0.1 moles in 100 steps SAVE solution 1 SELECTED_OUTPUT -file ex26.txt -step true -pH true -pe true -reaction true -temperature true -alkalinity true -si CO2(g) CH4(g) N2(g) NH3(g) -gases CO2(g) N2(g) NH3(g) -totals Ca Na Cl S(6) N(5) Na K -molalities Ca+2 Na+ Cl- END