While buying and processing Eagle Ford crude oil from Texas, a large amount of methanol was discovered in Light Naphtha (About 700 ~ 800 ppm). Methanol was expected to be mostly removed from the Desalter, but after checking the samples at the front and rear of Desalter, the reduction rate was around 10%. The Desalter temperature and pressure conditions have been checked, but the phase may not be changed. Can you explain why methanol is not removed?