Miniscale Fractional Unpacked Distillation Lab Report

Feras Kaid

Chem 2415-43

TA: Rio

Assessment 1

Conclusion

In this lab, there were 4 different distillations that were performed each with the same end goal to separate the two different organic compounds, cyclohexane and toluene. We used the boiling points of the two compounds to separate them using the following 4 techniques: microscale simple distillation, miniscale simple distillation, miniscale fractional packed distillation, and miniscale fractional unpacked distillation. The three different miniscale distillations were used to predict the accuracy of the distillation by comparing them to one other. The most accurate of the three distillations is the miniscale fractional packed distillation because this type uses a Vigreux column instead

The Vigreux column has a larger surface area and creates more area for the distillate to condense back into the starting solution. Although the miniscale fractional unpacked distillation is relatively accurate compared to the simple miniscale distillation, the miniscale fractional packed still seems to be the most accurate out of the three. The air condenser in the miniscale fractional packed distillation allows for an extra-added surface area that allows for a greater amount of the liquid to distill separately. The miniscale simple distillation is the least accurate because there is no extra column such as the Vigreux column or the condenser that is added to increase the surface area so therefore any of the vaporized liquid can readily enter the water condenser and condense into the distillate. The 4th technique that was used is called the microscale simple distillation, which is used when there is a relatively small amount of liquid than that used for any of the miniscale techniques. For the miniscale techniques used in this lab, 10 mL of cyclohexane was used and 20 mL of toluene was used. For the microscale technique,

The initial mole ratio values for the miniscale distillations were 0.329 for cyclohexane and 0.671 for toluene so there is a ratio of 1:3 when comparing cyclohexane to toluene. For the miniscale fractional unpacked distillation, the final mole fractions were .190 for cyclohexane and .810 for toluene and so the rounded ratio of the cyclohexane to toluene was 1:5. . For the miniscale simple distillation, the final mole fraction values were 0.225 for cyclohexane and 0.775 for toluene and so the ratio for the miniscale simple distillation is approximately 1:4 when comparing cyclohexane to toluene. And for the miniscale fractional Vigreux column distillation the final mole fractions were .293 for cyclohexane and .707 for toluene so the rounded molar fraction of the miniscale fractional Vigreux column distillation was 3:10. With these values we can see that the miniscale fractional packed distillation was the most accurate and then miniscale simple distillation and then miniscale fractional unpacked. This is a little odd because according to the theoretical; miniscale fractional unpacked would be more accurate than the miniscale simple distillation. But still, the most accurate results we received were from miniscale fractional packed distillation, the one that had used the Vigreux column as expected from the theoretical. On the other hand, for the microscale simple distillation,