Evaporation Finale 2

7/24/2019 Evaporation Finale 2

1/13

EVAPORATION USING ETHANOL SOLUTION

Principles

Evaporation is the process of converting liquid substances to vapor. The term evaporation is

commonly associated with the removal of water from an aqueous solution. The primary purpose

of evaporation in the industry is to create a concentrated solution by evaporating the more

volatile component in the dilute solution.

The basic factors that affect the rate of evaporation are the:

rate of heat application,

latent heat of vaporization,

maximum allowable temperature of the liquid,

pressure of surroundings

Rotary Evaporation

Rotary evaporation is the process of reducing the volume

of a solvent by distributing it as a thin film across the

interior of a vessel at elevated temperature and reduced

pressure. hen the vapor pressure of the liquid reaches

the pressure of its surroundings, the liquid boils. The

relationship between vapor pressure and boiling

temperature, for water, is shown in !igure ". herein the

reduced pressures required to boil the liquor at lower

temperatures are obtained by mechanical or steam #et

e#ector vacuum pumps, combined generally with

condensers for the vapors from the evaporator. This

promotes the rapid removal of excess solvent from less

volatile samples.


2/13

$ost rotary evaporators have four ma#or components: heat

bath, rotor, condenser, and solvent trap. %dditionally an

aspirator or vacuum pump needs to be attached, as well as a

bump trap and round bottom flas& containing the sample to be

concentrated. !igure ' shows the different parts of a rotary

evaporator.

Figure 2. A Hei-VAP Precision Rotary ea!orator "it# g$ass"are set G%

& (rive unit with vapor tube and coupling clamp duct 2 Evaporator flas&

% )eating bath ' *ase unit ( +ontrol panel ) Receiving flas& * +ondenser

Mass and Heat Balance in the Rotary Evaporator

The rotary evaporator is an example of a single evaporator, operating under well mixed

conditions and feed solute concentration is less than the product solute concentration. Referring

to !igure the material balance equation gives

F L V= +

Figure &. Va!or !ressure ersus

te+!erature cure ,or "ater

#tt!//""".n0i,st.org.n0/unito!erations

/1rying&.#t+a!!resste+!3

(1)


3/13


4/13

Concentrate L

T1, xL

T Temperature

x, y mole fraction

P1

At time t = 0

Feed F with Ti, xi

cold water S

TS

warm water S

TS

CondensateV

T1, yv

!igure . -etup (iagram -ource: -)/0/1 2 +/., 3T(.,. 4Rotary Evaporator4. "556: n.

pag. 7rint.


5/13

!or the solute balance, assuming that the vapor does not contain any amount of solute 8i.e. y v9

;

F LFx Vy=

O45E6TIVES

The ob#ective of this experiment is to familiarize the evaporation process using Ethanol solution

at different evaporating time intervals and to determine the rate of evaporation. "The

experimenter will be able to design and conduct experiment to test hypotheses and verify

assumptions, as well as to analyze and interpret data from simulated processes and present

results to a community of experts orally or in print. '$oreover, the experimenter should be able

to communicate ideas, propositions, results, and solutions preferably in English language or in

any appropriate medium easily understood by a target audience.

7ATERIALS AN8 E9UIP7ENT

Chemicals Equipment

5< = by volume Ethanol -olution Rotary evaporator setup


6/13

. 3oad about '


7/13

"@. Transfer the contents from the round bottom flas& to a separate flas&. $easure the

volume of the condensate using a graduated cylinder and record the volume in Table

."A. Repeat the process for the different time intervals, with varying rotating speed and

temperature.

"B. %fter all the evaporation are done, press the main power button to turn the rotaryevaporator off. $a&e sure the temperature dial is set to zero. f the entire system was

lowered in step Bb, the system will raise to its original height.

"5. Turn off the vacuum pump.'. -lowly vent the system by turning the release valve at the top of the condenser to the

open position.

II. Resu$ts

". Tabulate the results in the tables provided.'. 7lot the volumes of Ethanol condensate from the different variables against time.

. +alculate the rate of evaporation using the slope of the plotted curve in 8';.


8/13

Ta:$e &a. Time ntervals for the Evaporation of Ethanol -olution Dnder +onstant

Temperature and Facuum 7ressure 8Trial ";

Rotationa$ S!ee1

(; r!+ &;; r!+ &(; r!+

Ti+eIntera$

Ti+eStarte1

Ti+eFinis#e1

Ti+eStarte1

Ti+eFinis#e

1

Ti+eStarte1

Ti+eFinis#e

1

"< mins.

mins.

6< mins.

@ mins.

Ta:$e &:. Time ntervals for the Evaporation of Ethanol -olution Dnder +onstant

Temperature and Facuum 7ressure 8Trial ';

Rotationa$ S!ee1

(; r!+ &;; r!+ &(; r!+

Ti+e

Intera$

Ti+e

Starte1

Ti+e

Finis#e1

Ti+e

Starte1

Ti+e

Finis#e

1

Ti+e

Starte1

Ti+e

Finis#e

1

"< mins.

mins.

6< mins.

@ mins.

Ta:$e &c. Time ntervals for the Evaporation of Ethanol -olution Dnder +onstant

Temperature and Facuum 7ressure 8Trial ;

Rotationa$ S!ee1

(; r!+ &;; r!+ &(; r!+

Ti+e

Intera$

Ti+e

Starte1

Ti+e

Finis#e1

Ti+e

Starte1

Ti+e

Finis#e

1

Ti+e

Starte1

Ti+e

Finis#e

1

"< mins.

mins.6< mins.

@ mins.


9/13

Ta:$e 2a. Time ntervals for the Evaporation of Ethanol -olution Dnder +onstant

Rotational -peed and Facuum 7ressure 8Trial ";

Te+!erature);


10/13

Ta:$e %a.Folume Readings of the Ethanol +ondensate 8"< mins Time nterval;

Initia$ Vo$u+e Fina$ Vo$u+e

Tria$ & Tria$ 2 Tria$ %

Un1er 6onstant Te+!erature


11/13

Ta:$e %1.Folume Readings of the Ethanol +ondensate 8@ mins Time nterval;

Initia$ Vo$u+e Fina$ Vo$u+e

Tria$ & Tria$ 2 Tria$ %



12/13

Ta:$e '.-ummary of Ethanol +oncentrations

Et#ano$ 6oncentration> 7

Tria$ & Tria$ 2 Tria$ % Aerage



13/13

REFEREN6ES

#tt!s//engineering.!ur1ue.e1u/Po"er$a:/Stan1ar1?2;O!erating?2;Proce1ures/Rotary

?2;Ea!orator?2;SOP3.!1,

8ate accesse1 August 22> 2;&(

#tt!//c#e+"[email protected]/Re,erence/La:Tec#niBues/RotaryEa!oration >


#tt!s//""".youtu:e.co+/"atc#CD;(y"%)GL%I

8ate accesse1 August 2;> 2;&(

#tt!//""".ecsgreen.co+/!rocesso,ea!oration.#t+$


#tt!//""".n0i,st.org.n0/unito!erations/1rying&.#t+a!!resste+!


#tt!//""".goog$e.co+/!atents/EP;'%%*24&Cc$Den

https://engineering.purdue.edu/Powerlab/Standard%20Operating%20Procedures/Rotary%20Evaporator%20(SOP).pdfhttps://engineering.purdue.edu/Powerlab/Standard%20Operating%20Procedures/Rotary%20Evaporator%20(SOP).pdfhttp://chemwiki.ucdavis.edu/Reference/Lab_Techniques/Rotary_Evaporationhttps://www.youtube.com/watch?v=05yw3K6GL3Ihttp://www.ecsgreen.com/processofevaporation.htmlhttp://www.nzifst.org.nz/unitoperations/drying1.htm#vappresstemphttp://www.google.com/patents/EP0433729B1?cl=enhttp://chemwiki.ucdavis.edu/Reference/Lab_Techniques/Rotary_Evaporationhttps://www.youtube.com/watch?v=05yw3K6GL3Ihttp://www.ecsgreen.com/processofevaporation.htmlhttp://www.nzifst.org.nz/unitoperations/drying1.htm#vappresstemphttp://www.google.com/patents/EP0433729B1?cl=enhttps://engineering.purdue.edu/Powerlab/Standard%20Operating%20Procedures/Rotary%20Evaporator%20(SOP).pdfhttps://engineering.purdue.edu/Powerlab/Standard%20Operating%20Procedures/Rotary%20Evaporator%20(SOP).pdf

Documents

Evaporation Finale 2