How can the thermal conductivity of a binary gas mixture be estimated? Recently, I am seeking for a simple but relatively accurate method to estimate the thermal conductivity of a binary gas mixture, say ethanol vapor + nitrogen. I assume the mixture as ideal gas. 

The molar fraction and thermal conductivities of the components are known. The parameters for a try are: mole fraction of ethanol vapor: $x_A=0.2$, thermal conductivity of ethanol vapor and nitrogen are $k_A=0.016\ \mathrm{W/(m\,K)}$, $k_B=0.026\ \mathrm{W/(m\,K)}$, temperature of the mixture gas $T=330\ \mathrm{K}$, and the bulk pressure is $101\ \mathrm{kPa}$.

I really hope someone could give me a hint or point me to a classical reference.
Thank you in advance!
I'm thinking you could use the Fourier equation for heat flux

$$
\phi =K \frac{S\theta}{e} \,\, ,
$$
where


$\phi$ = Heat flux
$K$ = Termal conductivity coeficient in units of  $kcal  s^{-1}\ m^{-2}\ K^{-1} /m^{-1}$
$S$ = Area of the section you're dealing $m^{2}$
$θ$ = Difference of temperature $K$
$e$ = Thickness in $m$.


And use for the resulting thermal conductivity the fraction

$$
K_{r}=\frac{\sum K_{i}J_{i}(M_{i})^{1/3}}{\sum J_{i}(M_{i})^{1/3}} \,\, ,
$$
where:


$K_{r}$ = Resulting termal conductivity of the moisture;
$K_{i}$ = Termal conductivity of each gas;
$j_{i}$ = Molar fraction of each gas;
$M_{i}$ = molar mass of each gas.


I think it'll work with some 2% of standard deviation. If you're able to read in portuguese, here is the link of my reference:

Reference

And here is the link of the Book cited by @Chester Miller.

I hope I hope I was Helpfull!