pH variation

[INZILLO]

Hi everyone,
starting from seawater, I need to gradually add a 0.2 L solution of 1 M NaOH. The goal is to determine the maximum amount of NaOH I can add before any phase starts to precipitate.

Below is the code I?ve written so far.

Thanks in advance!

SOLUTION 1 Sea
    temp      25
    pH        7.45
    pe        4
    redox     pe
    units     mg/l
    density   1.011
    Br        59
    Ca        425
    Cl        16121
    K         321
    Mg        1121
    Na        10085
    S(6)      778 as SO4
    Sr        1
    -water    1 # kg
end

SOLUTION 2 Reactant NaOH
    temp      25
    pH        14
    pe        4
    redox     pe
    units     mol/l
    density   1
    NaOH      0.2
 -water    0.2 # kg
end

MIX 1
    1    0.9
    2    0.1

[dlparkhurst]

Incremental mixing requires a MIX definition for each mixture, which is cumbersome.

The change in volume should be small, so I would simply add NaOH with REACTION. If you want, you can go back and test the difference between actually mixing the NaOH solution relative to adding NaOH alone.