Loading presentation...

Present Remotely

Send the link below via email or IM

Copy

Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.

DeleteCancel

Make your likes visible on Facebook?

Connect your Facebook account to Prezi and let your likes appear on your timeline.
You can change this under Settings & Account at any time.

No, thanks

CITRIC ACID

No description
by

muzzaffar zaidi

on 16 December 2013

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of CITRIC ACID

PROCESS BACKGROUND
How to synthesis citric acid??


It can be synthesized by using Aspergillus niger strain.

What you need??

A culture of Aspergillus niger

METABOLIC PATHWAYS OF SYNTHESIS OF CITRIC ACID
Explaination
Citric acid is a weak organic acid that is an important intermediate in the Krebs cycle.

It breaks down glucose to citric acid and carbon dioxide with the presence of oxygen.

Due to its branching structure of white septate hypha

It the capabilities to utilize varieties of substrates

Why Aspergillus Niger?

CONT~
The process starts with the glycolysis of glucose. In this stage, glucose is splitted into two 3-carbon molecule known as pyruvate @pyruvic acid. As pyruvic acid enter the mitochondrion, carbon is removed, forming carbon dioxide,CO2, and electrons are removed, changing the NAD+ to NADH. Co-enzyme A joins the 2-carbon molecule, forming Acetyl-CoA. Acetyl-CoA then adds the 2 carbon acetyl group to a 4-carbon compound, forming the citric acid.
However, the citric acids need to be extracted. Below are few stages where the extraction process took place.
A. Cell growth in each phases

Log of growth with time
ln⁡xt = ln⁡xo +μt

Cube root of growth linear with time

〖xt^(1/3) =〖xo^(1/3)+kc t
Linear with time

xt=xo+kc t

Where xt=biomass concentration of time, t
μ=specific growth rate
k_c,k_t=constant

B. Product formation
It is related to the growth rate
rp = (a.rx )+(b.x)
Where x=biomass concentration
rx=rate of biomass accumulation

Rate of product formation is proportional to the rate at which the cells entered the maturation state,
rpt=krx (t-tm)
Where (t-t_m )=rate of biomass growth at time,t

Primarily, the production of citric acid starts with the reaction of sugar and Aspergillus niger as shown below
Addition of sulphuric acid

(C6H507)2.Ca3.4H2O + 3H2SO4
Calcium nitrate sulphuric acid citric acid

2C6H8O7+3CaSO4.2H2O+2H20
calcium sulphate water

REACTION MECHANISM
C6H12O6+A.niger C6H806+CO2

Sugar citric acid carbon dioxide
Addition of calcium hydroxide
2C6H807 + 3Ca(OH)2 (C6H507)2.〖Ca3.4H2O+2H2O

The solution is then centrifuged at 3000rev/min for 10minutes then dried overnight at room temperature to get a crystallized product of citric acid.
However, there is a problem in this equation as the k is not constant. It kept increasing. So we resolve the problem by assuming that there were at least two different types of cells within the mycelium and both have different productivity. This equation is modified and become
rpt=k1 rx (t-tm )+k2 x(t-tm)

K1=growth associated constant
K2= non growth associated constant

CITRIC ACID
DEFINITION

a weak organic acid

important intermediate in Krebs Cycle

FUNCTION

Breaks down glucose

With the presence of Oxygen

Citric Acid + CO2

to form
SOURCES

Citrus fruits

grapefruits

orange

lemon

&
All living things

APPLICATION

Antioxidant
Artificial flavouring

For chemical-processed food

METHOD OF PRODUCTION

Mostly by using Aspergillus niger

by utilizing starchy and sugar substrate

It can be found in citrus fruits such as grapefruits, orange, lemon and etc as well as in all living things.

Citric acid has been widely used as an antioxidant and as an artificial flavouring in chemical-processed food. It is usually produced by Aspergillus niger by utilizing starchy and sugar substrate.

Table Sugar

Calcium hydroxide

Sulphuric acid

Procedure
Add sugar into Aspergillus niger

Fungus will recycle sugar into citric acid and carbon dioxide

Filter and extract the citric acid by adding calcium hydroxide

Calcium hydroxide react with acid to form salt that is calcium nitrate that will precipitate.

Scoop the salt and add sulphuric acid into it


Crystallized precipitate will form but you do not need it.. you will only require the liquid solution which is the pure citric acid.

Citric acid calcium hydroxide calcium nitrate water
REACTION KINETICS
REACTOR SELECTION
The reactor selected in the production of citric acid is batch reactor as shown in the schematic diagram below
A bioreactor is a vessel in which an organism is cultivated and grown in

control manner to form byproduct.
consist of ;

• agitation system which will mix the organism completely
• control panel which regulates pumps cooling water , pump air supply and acid/base supply
• sensors-check medium temperature, medium aeration and medium pH value

• There is steam supply to the system
• Thermal jacket
• Tedium air supply and cooling water
supply to control the temperature in the reactor

selection of reactor

Batch reactor

It is a strirred fermenter

Size of bioreactor

For laboratories scale 2-100litre

Sources of sugar &pH plays a major role in Citric Acid production

Process involved

Anaerobic process

It used strain Aspergillus niger

For industrial scale up to 100m3
Full transcript