Question

Differencr between nitrogen evaporator n rotary evaporator

Answer 1

Explanation:

Isolation of organic constituents from water frequently involves an extraction with a large volume of organic solvent which must be reduced to achieve the desired sensitivity. The objective of this research was to evaluate common solvent evaporation techniques to determine which are acceptable for use in pollutant analysis. Techniques for solvent reduction from 200 to 10 mL (macro) and 8 to 0.2 mL (micro) were evaluated. The macro concentration technques included Kuderna-Danish (K-D) concentration, rotary evaporation, evaporation on a hot plate in an Erlen-meyer flask, and heated nitrogen blowdown in an Erlenmeyer flask. The micro techniques included micro K-D concentration, nitrogen blowdown, and nitrogen blowdown with a modified Snyder column. A series of model compounds covering a wide range of boiling points (108° to 323°C) and polarity was used. Based upon recovery efficiency alone, nitrogen blowdown was significantly superior to the other macro techniques; however, its extreme slowness gave K-D the highest Figure of Merit. With methylene chloride as the solvent, nitrogen blowdown with a column was the superior technique.

Answer 2

The change of liquid into its vapour form at any temperature point is called as evaporation. Evaporation is a surface phenomena.

» The conditions that increases the rate of evaporation are :-

→ Increase in Temperature :- The increase in temperature makes evaporation faster.

→ Increase in Surface area :- Increasing the surface area also makes evaporation faster.

→ Increase in wind speed :- Increasing the wind speed increases evaporation rate.

→ Decreasing humidity :- Decreasing humidity increases the rate of evaporation for water.