Methanol reading on GC-LSV varies with pressure
Posted: Sun Jun 18, 2017 3:07 am
Hi,
We are measuring Oxygenates in C4 Hydrocarbons stream in Liquid phase, on a Gas Chromatograph with LSV. Bubble point is calculated as 3.91 bar and we are keeping the sample pressurized with a Back pressure regulator set at 5 barg. The process pressure is at 12 barg
We observe that the Methanol value reads low and Tert-Butanol reads high when pressure kept at 5 barg whereas the Methanol value increases and Tert-Butanol value decreases, with increase in pressure upto process pressure of 12 barg.
Can you please help understand this phenomenon? I do not have deep understanding of chemistry. But what i expect is that if the liquid is kept above its bubble point, Methanol or even other components should not be vaporizing and thus causing such phenomenon.
We are measuring Oxygenates in C4 Hydrocarbons stream in Liquid phase, on a Gas Chromatograph with LSV. Bubble point is calculated as 3.91 bar and we are keeping the sample pressurized with a Back pressure regulator set at 5 barg. The process pressure is at 12 barg
We observe that the Methanol value reads low and Tert-Butanol reads high when pressure kept at 5 barg whereas the Methanol value increases and Tert-Butanol value decreases, with increase in pressure upto process pressure of 12 barg.
Can you please help understand this phenomenon? I do not have deep understanding of chemistry. But what i expect is that if the liquid is kept above its bubble point, Methanol or even other components should not be vaporizing and thus causing such phenomenon.