Question

I am currently in the process of trying to get toluene free of carbonyl compounds using a distillation processes with DNPH.

Unfortunately I am no distillation expert. And am running into some problems.

The method is take one liter of toluene and 4g of dnph and 0.5 ml of HCl. all technical grade. Reflux for 2 hours and distill. Discard the first 50 ml.

DNPH has a amount of water. That's I assume you need to discard the first 50ml

Apparently when distilling you need a fractional column. Don't know why but assume that compound with a boiling point that differs from the clean toluene.

Now the problem is I do not get clean toluene. I think this has something to do with the boiling point of hydrazine. This has almost the same boiling point as toluene. How would one get better separation in a distillation process?

Answer 1

To achieve better separation in a distillation process, a fractional column is required. This column provides more opportunities for distillation and condensation, allowing compounds with different boiling points to separate effectively.

Step-by-step explanation:

When conducting a distillation process to remove carbonyl compounds from toluene using DNPH, achieving better separation requires the use of a fractional column.

A fractional column has a series of plates or packing material that increases the surface area available for separation during distillation.

Each plate or packing has a different temperature, which allows compounds with different boiling points to vaporize and condense at different heights, leading to better separation.

In the case of hydrazine, which has a similar boiling point to toluene, the use of a fractional column can help separate it from clean toluene.

The column provides more opportunities for distillation and condensation, allowing the toluene and hydrazine to separate based on their different boiling points.