Dear Sir a Madam:
>
> My name is Ana Belen and I am a student of Chemical Engineering.
Actually I am working in my degree dissertation, which subject is : : "Recovery and Purification of Sugar Fatty Acid Diesters produced through Enzymatic Esterification" The reaction mixture to be separated is a solution of unreacted oleic acid, and diester in n-hexane. The aim of the project is developing a process to purify the ester, once separated from the mixture. At the same time, the recovery of the oleic acid is interesant from an economic point of view, in order to recycle it back to the reactor.
I have decided to carry out the purification of the ester using an adsorption
chromatography technique. According to the literature, the separation of the ester from the fatty acid can be achieved by means of a silica gel 60 column chromatography (particle diameter: 0,015 mm-0,04 mm). After some previous experiments using TLC to determine the most suitable eluyent for the column, I have decide to use first ethyl acetate to remove the fatty
acid, then a ethyl acetate/methanol (80/20 v/v) mixture to remove the
diester.

Actually, I am working in the determination of the main parameters of the column (porosity, dead volume, retention time…..).
I would like to evaluate the dead time for the column, but I do not know which is the most adequate compound for this purpose. I have to choose a compound which is unretained in the column but at the same time, easily detected.
Could you give some advice?

what detector do you use?

I am thinking about using an espectophotometer detector, since it is the equipment available in our department. Could you give some suggestions about another detectors commonly used? Thanks

Toluene is ok.