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# Kinetic dissolution of kaolinite RATESKaolinite # from Marty et al 2015# pre-exponent coefficient A is calculated from logk using equation A=k/exp(-Ea/RT)# experimental condition range T=22-80C, pH=0.5-12-start1 rem unit should be mol,Liter-1 and second-12 rem parm(1) is surface area in the unit of m2/L 3 rem calculation of surface area can be found in the note 4 rem M is current moles of minerals5 rem M0 is the initial moles of minerals6 rem parm(2) is a scaling factor10 rem acid solution parameters11 a1=2.56E-0412 E1=4300013 n1=0.5120 rem neutral solution parameters21 a2=5.0E-0822 E2=3800030 rem base solution parameters31 a3=2.87E-0332 E3=4600033 n2=0.5836 rem rate=0 if no minerals and undersaturated40 SR_mineral=SR("Kaolinite")41 if (M<0) then goto 20042 if (M=0 and SR_mineral<1) then goto 20043 if (M0<=0) then SA=PARM(1) else SA=PARM(1)*(M/M0)^0.6750 if (SA<=0) then SA=160 R=8.3145175 Rate1=a1*EXP(-E1/R/TK)*ACT("H+")^n1 #acid rate expression80 Rate2=a2*EXP(-E2/R/TK) #neutral rate expression85 Rate3=a3*EXP(-E3/R/TK)*ACT("OH-")^n2 #base rate expression90 Rate=(Rate1+Rate2+Rate3)*(1-Sr_mineral)*SA*parm(2)100 moles= Rate*Time110 rem do not dissolve more minerals than present115 if (moles>M) then moles=M200 save moles-endKINETICSKaolinite -m0 0.387 # initial moles of kaolinite -parms 2380 1 -time_step 0.01 day in 400 # X days in Y stepsINCREMENTAL_REACTIONS trueSOLUTION 1 -water 0.5 -temp 200USER_GRAPH -chart_title "Kaolinite dissolution" -axis_titles Hours "SR" "KIN_DELTA" #-axis_titles ACT("H+") "SR" -initial_solutions true -start 10 graph_x total_time / 3600 # time in hours on x-axis 20 graph_y SR("Kaolinite") #30 graph_sy -la("H+") #30 graph_sy KIN_DELTA("Kaolinite") 30 graph_sy Rate1 #30 PLOT_XY ACT("H+"),SR("Kaolinite") -endEND

graph_sy Rate1

# Kinetic dissolution of kaoliniteRATESKaolinite# from Marty et al 2015# pre-exponent coefficient A is calculated from logk using equation A=k/exp(-Ea/RT)# experimental condition range T=22-80C, pH=0.5-12-start1 rem unit should be mol,Liter-1 and second-12 rem parm(1) is surface area in the unit of m2/L3 rem calculation of surface area can be found in the note4 rem M is current moles of minerals5 rem M0 is the initial moles of minerals6 rem parm(2) is a scaling factor10 rem acid solution parameters11 a1=2.56E-0412 E1=4300013 n1=0.5120 rem neutral solution parameters21 a2=5.0E-0822 E2=3800030 rem base solution parameters31 a3=2.87E-0332 E3=4600033 n2=0.5836 rem rate=0 if no minerals and undersaturated40 SR_mineral=SR("Kaolinite")41 if (M<0) then goto 20042 if (M=0 and SR_mineral<1) then goto 20043 if (M0<=0) then SA=PARM(1) else SA=PARM(1)*(M/M0)^0.6750 if (SA<=0) then SA=160 R=8.3145175 Rate1=a1*EXP(-E1/R/TK)*ACT("H+")^n1 #acid rate expression80 Rate2=a2*EXP(-E2/R/TK) #neutral rate expression85 Rate3=a3*EXP(-E3/R/TK)*ACT("OH-")^n2 #base rate expression90 Rate=(Rate1+Rate2+Rate3)*(1-Sr_mineral)*SA*parm(2)100 moles= Rate*Time110 rem do not dissolve more minerals than present115 if (moles>M) then moles=M200 save moles210 PUT(rate1 *(1-Sr_mineral)*SA*parm(2), 1)220 PUT(rate2 *(1-Sr_mineral)*SA*parm(2), 2)230 PUT(rate3 *(1-Sr_mineral)*SA*parm(2), 3)-endKINETICSKaolinite -m0 0.387 # initial moles of kaolinite -parms 2380 1 -time_step 0.01 day in 400 # X days in Y stepsINCREMENTAL_REACTIONS trueSOLUTION 1 -water 0.5 -temp 200USER_GRAPH -chart_title "Kaolinite dissolution" -headings hours Si Rate1 Rate2 Rate3 Rate -axis_titles Hours "Si, mol/kgw" "Rate, mol/s" -axis_scale sy_axis auto auto auto auto log -initial_solutions true -start 10 graph_x total_time / 3600 # time in hours on x-axis 20 GRAPH_Y TOT("Si") 30 GRAPH_SY GET(1), GET(2), GET(3), -KIN_DELTA("Kaolinite") / KIN_TIME -endEND

Kaolinite -m0 0.387 # initial moles of kaolinite -parms 6150 1 #2380 1

43 if (M0<=0) then SA=PARM(1) else SA=[PARM(1)* M0] * (M/M0)^0.67