Cstr

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ABSTRACT
In the majority field of chemical processes, the reactor vessel in which the reaction process take place is the key component of the equipment.The design of the reactors is very important to the success of the production. In this experiment, sodium hydroxide and ethyl acetate react in tubular flow reactor.Both of the reactants fed to the reactor at equimolar flowrate for a certain time.The reaction is carried out at different volumetric flowrate.The conductivity value of outlet stream is measured to determine the conversion achieve at different retention time. The retention time is highest for the lowest flowrate. The result shows that the conversion is increases as the residence time increases.

INTRODUCTION
Reactor is one of the most important parts in industrial sector. Reactor is equipment that changes the raw material to the product that we want. A good reactor will give a high production and economical. One of criteria to choose or to design a good reactor is to know the effectiveness of the reactor itself. There a many types of reactor depending on the nature of the feed materials and products. One of the most important we need to know in the various chemical reaction was the rate of the reaction.

By studying the saponification reaction of ethyl acetate and sodium hydroxide to form sodium acetate in a batch and in a continuous stirred tank reactor, we can evaluate the rate data needed to design a production scale reactor.

A stirred tank reactor (STR) may be operated either as a batch reactor or as a steady state flow reactor (CSTR). The key or main feature of this reactor is that mixing is complete so that properties such as temperature and concentration of the reaction mixture are uniform in all parts of the vessel. Material balance of a general chemical reaction described below.The conservation principle requires that the mass of species A in an element of reactor volume dV obeys the following statement: (Rate of A into volume element) - (rate of A out of volume element) + (rate of A produced within volume element) = (rate of A accumulated within vol. element)

THEORY

General Mole Balance Equation

Assumptions
1) Steady state therefore
2) Well mixed therefore rA is the same throughout the reactor

Rearranging the generation

In terms of conversion

The reaction to be studied is the saponification reaction of ethyl acetate Et(Ac) and sodium hydroxyde NaOH.Since this is a second order of reaction, the rate of reaction depends on both of these reactants.The reaction will be acrried out using equimolar feeds of both the reactants with same initial concentrations.The raction equation is; NaOH + Et (Ac) →Na(Ac) + EtOH

or
A + B → C + D
For a second order equimolar reaction with the same initial concentration (CAO = CBo), the rate law is; -ra=kCACB=kCA2
-rA= VCSTRFA0X
Thus, the volume of the reactor is ;
VCSTR = FA0XkCA2= F0(CAo-CA)kCA2
For equimolar feed rate, the reaction constant is ;
k=(CAo-CA)τCA2
The residence time of a chemical reactor or vessel is a description of the time that different fluid elements spend inside the reactor is given by ; Residence time, τ=VCSTRF0
OBJECTIVE
1. To carry out a saponification reaction between sodium hydroxide,NaOH and ethyl acetate Et(Ac) in a CSTR 2. To determine the reaction rate constant of sodium hydroxide,NaOH and ethyl acetate Et(Ac) 3. To determine the effect of residence time on the conversion in a CSTR.

APPARATUS
1. A laboratory scale of Continuous Stirred Tank Reactor 2. A conductivity meter
3. 50 mL Beakers
4. 250 mL Conical Flasks
5. A burette
6. A retort stand.
7. Sodium Hydroxide
8. Ethyl acetate
9. Hydrochloric acid
10. Phenolphtalein
11. Deionized water

PROCEDURE
a) Preparation of Calibration Curve
1. 1 Liter of sodium hydroxyde,NaOH (0.1M) and 1 Liter of sodium acetate,Na(Ac) (0.1M) was prepared. 2. The conductivity and NaOH...
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