UNIFAC (NIST-KT)
Back to UNIFAC (NIST-KT) (Ternary)
ln(γj) = ln(γj,c) + summation from i = 1 to N of [nj,i × {ln(γi)-γj,i}] where
ln(γj,c) = ln(Φj / xj) + 5 × qj × ln(Θi / Φi) + lj - (Φj / xj)× the summation from k=1 to 3 of [xk × lk]
Θi = xi × qj / summation from j=1 to 3 of [xj × qj]
Φi = xi × rj / summation from j=1 to 3 of [xj × rj]
lj = 5 × (rj - qj) + 1 - rj
γj,k = Qtype(k) × {1 - (summation from i=1 to N of [θj,i × Ψki] / summation from m=1 to N of [θj,m × Ψmi]) - ln(summation from i=1 to N of [θj,i × Ψki])}
γk = Qtype(k) × {1 - (summation from i=1 to N of [θM,i × Ψki] / summation from m=1 to N of [θM,m × Ψmi]) - ln(summation from i=1 to N of [θM,i × Ψki])}
xj,i = nj,i / summation from m=1 to N of [nm,i ]
θj,i = xj,i × Qtype(i) / summation from i=1 to N of [xj,i × Qtype(i)]
xM,i = summation from m=1 to 3 of [xm × nm,i] / summation from k=1 to N of [summation from m=1 to 3 of [xm × nm,k]]
θM,i = xM,i × Qtype(i) / summation from i=1 to N of [xM,i × Qtype(i)]