FIELD OF THE INVENTION;
This invention relates to a process for the estimation of water content in
oils.
BACKGROUND OF THE INVENTION;
The presence of water in oils is has an important bearing on its end
applications and hence its precise and accurate estimation is very
important. In order to ascertain the water content in oils, the commonly
used method is the distillation process as per IS: 1448 [P:40]-1987,
where the material is heated with a water immiscible solvent which co-
distils with the water in sample.
The method existing in the prior art employs solvents such as toluene or
xylene, and the oil sample is heated with the solvent. The condensed
distillate discharged from the reaction vessel is a mixture of solvent and
water and the water is collected and measured. The remaining solvent
and sample is discarded and this renders the process hazardous. The
discarded solvent is nothing but toluene or xylene and its disposal is

hazardous from an environment perspective. It was therefore felt
worthwhile to look for a way of reutilizing the left over solvent.
OBJECTS OF THE INVENTION;
It is an objection of this invention to propose a process for the estimation
of water content in oils, which is cost-effective.
It is a further of object of this invention to propose a process for the
estimation of water content in oils, which is not hazardous to the
environment.
These and other object of the invention will be apparent from the ensuing
description.
BRIEF DESCRIPTION OF THE INVENTION;
According to this invention is provided a process for the estimation of
water content in oil, comprising the steps of adding a regenerated solvent
from the previous step, to a oil sample to obtain a mixture, following by
distillation of the mixture, allowing the distillate containing solvent and
water, to condense and collecting the condensed water and solvent in a
trap, measuring the volume of water collected, subjecting the remaining
solvent to regeneration and collecting the regenerated solvent for the next
measurement.

In accordance with this invention toluene or xylene generated from one
reaction is utilized in the next reaction. The oil sample and the
regenerated solvent are taken in a Dean and Stark apparatus and
distilled. The condensed distillate discharged from the condenser, is a
mixture of solvent and water. After evolution of water is complete, the
trap and its contents are cooled and the volume of water is measured.
The remaining solvent is then again subjected to regeneration and
collected separately for the next measurement.
In order to ensure the properties of the solvent are intact, the left over
mixture of toluene or xylene and oil (if any) are fractionally distilled for
generation of toluene and separation of oil. The toluene or xylene distils
out at its boiling point and is then collected separately and stored.
The invention will now be explained in greater detail with the help of the
following non-limiting example.
EXAMPLE;
100 ml of oil sample and 100 ml of regenerated toluene/xylene were
taken in the round -bottom flask of a Dean-stark Apparatus and heated

with a Bunsen burner, after adding glass beads to the mixture, to avoid
bumping during heating. The heating was controlled, so that liquid
distills out at the rate of 2-5 drops per second. The condensed liquid is a
mixture of solvent and water. The water was collected in a measuring
cylinder used as a trap, containing fused calcium chloride. Once the
evolution of water ceased, the trap and its contents were cooled and the
volume of water was measured. The water content of the oil sample was
calculated using a working formula.
The solvent remaining in the distillation apparatus is fractionally distilled
at 108°C in a Leibig's condenser and the regenerated solvent is collected.
In order to validate the modified method, experiments were carried out
using three different grades of oil having water contents in the range of
2-5%, 10-15% and 40-45% by the existing as well as the modified
method. The analytical results are given below:

The above results indicate good agreement between both the methods.
The method according to the invention utilizing regenerated toluene can
be used for the measurement of water in oil without affecting the
analytical accuracies.

We Calim:
1. A process for the estimation of water content in an oil sample comprising the step of:
adding a regenerated solvent selected from toluene and xylene to a oil sample to obtain
a mixture;
following by distillation of the mixture;
allowing the distillate containing solvent and water, to condense and collecting the
condensed water and solvent in a trap, measuring the volume of water collected,
subjecting the remaining solvent to regeneration and collecting the regenerated
solvent for the next measurement
2. The process as claimed in claim 1, wherein the oil sample and the regenerated solvent
are mixed in equal volumes.
3. The process as claimed in claim 1, wherein the rate of distillation is so adjusted that the
condensed distillate distils at the rate of 2-5 drops / second.
4. The process as claimed in claim 1, wherein the regenerated solvent is selected from
toluene and xylene.
5. The process as claimed in claim 1, wherein the trap contains fused calcium chloride.

6. The process as claimed in claim 1, wherein the remaining solvent is regenerated by
fractional distillation.
7. The process as claimed in claim 1, wherein the water content is calculated from the
formula,
% water = volume of water in trap / volume of sample x 100

ABSTRACT

Title: A PROCESS FOR THE ESTIMATION OF WATER CONTENT IN AN OIL
SAMPLE
A process for the estimation of water content in an oil sample comprising the step of:
adding a regenerated solvent selected from toluene and xylene to a oil sample to obtain a
mixture;
following by distillation of the mixture;
allowing the distillate containing solvent and water, to condense and collecting the
condensed water and solvent in a trap, measuring the volume of water collected,
subjecting the remaining solvent to regeneration and collecting the regenerated solvent for
the next measurement.