1. PRODUCTION OF BIODIESEL FROM HIGH ACIDIC RAW MATERIALS
Design and development of an heterogeneous catalytic process

2. PRODUCTION OF BIODIESEL FROM HIGH ACIDIC RAW MATERIALS
Design and development of an heterogeneous catalytic process
INDEX
Why biodiesel from High Acidic Raw Materials?
How can we make biodiesel?
Our proposal
The results
Discussion
Achievements
Glosary
FA = Fatty Acid
FFA = Free Fatty Acid
FAME = Fatty Acid Methyl Ester
TG = Triglycerides
DG = Diglycerides
MG = Monoglycerides
Aknowledgements

3. PRODUCTION OF BIODIESEL FROM HIGH ACIDIC RAW MATERIALS
Design and development of an heterogeneous catalytic process
Why biodiesel from High Acidic Raw Materials?
Waste oils
Animal fats
Tomorrow
Today
The first question, we should answer is why we should produce biodiesel from high acidic raw materials.
Today, the production of biodiesel from vegetable oils is well-known. This way of production requires extensive cultivation areas only for biodiesel production which leads to less food to fulfill population needs.
The production of biodiesel from waste oils and animal fats, fatty acid-rich raw materials, will decrease the use of cultivation areas for biodiesel production and, at the same time, valorizate a harmful residues. This technology has a social and enviromental benefit.
Requires extensive cultivation areas
Less food for Population needs

4. PRODUCTION OF BIODIESEL FROM HIGH ACIDIC RAW MATERIALS
Design and development of an heterogeneous catalytic process
How can we make biodiesel?
Alkaline Transesterification
Homogeneous
KOH
KOH
Developed Tecnology
Triglycerides
Methanol
FAME
Glycerine
Vegetable oils
How is biodiesel produced nowadays?
On one hand, starting from vegetable oils, that consist mainly of triglycerides, an alkaline transesterification is normally performed. This homogeneus reaction takes place in alkaline media, in the presence of KOH as catalyst. Triglycerides react with mehtanol to produce FAMEs, which is biodiesel, and glycerine as a subproduct.
On the other hand, the production of biodiesel from animal fats and waste oils, fatty acid-rich raw materials, consists of an acidic esterification in the presence of sulphuric acid as catalyst. Fatty acids react with methanol to produce FAME and water, that should be removed from reaction media to favour the reaction towards the product of our interest. The use of sulphuric acid as catalyst has many drawbacks:
because of its corrosive nature, the handling and storage of this product is always problematic.
The final product must be neutralized before commercialization as biodiesel.
The above reasons make the process expensive and not adequate from an enviromental standpoint.
Therefore, an innovative heterogeneous catalytic process is, more than ever, required to overcome the mentioned drawbacks.
Acidic Esterification
Homogeneous
Sulphuric acid
Drawbacks
Fatty Acids
Methanol
FAME
Water
Animal Fats
Waste Oils

5. PRODUCTION OF BIODIESEL FROM HIGH ACIDIC RAW MATERIALS
Design and development of an heterogeneous catalytic process
Our proposal: the Process
Catalysts
Lewatit GF-101
Amberlyst 39wet
Column
Our proposal is an heterogeneus catalytic process, using the sulphonic resins Lewatit GF-101 and Amberlyst 39wet as catalyst, in substitution of sulphuric acid.
In this pictures we can see the laboratory-scale pilot plant, where raw materials and methanol are mixed in the stirred tank. A HPLC pump drives the mixture through this column, filled of the sulphonic resin. Finally, the mixture is returned to the Stirred Tank.
Stirred Tank
Pump
“Heterogeneous Catalytic Process”

6. PRODUCTION OF BIODIESEL FROM HIGH ACIDIC RAW MATERIALS
Design and development of an heterogeneous catalytic process
Our proposal: Raw materials
ANIMAL FATS “Yellow Grease”. Acidity ~ 15%.
Proteins and Phospholipids
Physical extraction
Fe, P and S catalyst poisons
regulated by EN14214
OLEINEs Neutralized soapstock. Acidity ~ 75%
Proteins, Phospholipids, Glycerids
Neutralizing FFA with NaOH and acidification
Na > 1%
The raw materials used were:
Animal Fats, known as “Yellow Grease”, are extracted from animal tissues by melting and centrifugation. For this reason, fatty acids could be contaminated with proteins and phospholipids. Iron, phosphorus and sulphur can act as catalyst poisons. This raw material did not flow easily because of its low melting point. Animal fats often clogged pipes, becoming a problem.
Oleines are a subproduct of oil industry. An alkali (NaOH or KOH) is added to vegetable oil to precipitate soaps. This soaps are separated from triglycerides and neutralized to produce fatty acids. The neutralized soapstock is highly acidic and contains proteins, phospolipids, some glycerids and sodium or potassium. Metal cations may poison the active centres of catalysts.
Deodorization is a process to remove fatty acids from vegetable oils. These compounds are responsible of bad odours. The process is a distillation with steam. Highly-pure-fatty acid subproduct is obtained with 75% acidity.
DEODORIZATION DISTILLATE Acidity ~ 75%
Esentially Free Fatty Acids
Distillation of FFA with steam

7. PRODUCTION OF BIODIESEL FROM HIGH ACIDIC RAW MATERIALS
Design and development of an heterogeneous catalytic process
The results: Diluted oleine
15% w/w in sunflower oil 1 2 3 4 5 6
-10 10 20 30 40 50 60 70 80 90
100
Esterification Yield (%)
Time (hours) 
Low Esterification Yield (%) 
Production of Triglycerides
Results,
Using diluted oleine 15% w/w in sunflower oil as raw material, the results show a very low esterification yield. The chromatogram in the bottom-left corner shows an increase in triglycerides in the esterified product. Therefore, fatty acids react preferably with monoglycerides and diglyceridos rather than methanol.
Initial DG FA TG
Esterified
FAME

8. PRODUCTION OF BIODIESEL FROM HIGH ACIDIC RAW MATERIALS
Design and development of an heterogeneous catalytic process
The results: Diluted deodorization distillate
30% w/w in sunflower oil 1 2 3 4 5 6 7 8
-10 10 20 30 40 50 60 70 80 90
100
Time (hours)
Esterification Yield (%)
High Esterification Yield (%) 
Production of Triglycerides
Initial
Using diluted deodorization distillte 30% w/w in sunflower oil, results show a strong increase in Esterification Yield, but again the production of triglyceridos from mono and diglycerides is significant. Only fatty acid methyl esthers can be used for biodiesel. FA MG DG TG
Esterified
FAME

9. PRODUCTION OF BIODIESEL FROM HIGH ACIDIC RAW MATERIALS
Design and development of an heterogeneous catalytic process
The results: Non diluted oleine
75% free fatty acids 10 20 30 40 50 60 70 80 90
100 1 2 3 4 5 6 7 8 9 11 12
Methyl ester (%)
Esterification Yield (%)
10% Free acidity
Triglycerides
Destillation
Final 1% p/p FFA
EU14214
Esterification Yield (%)
Using non diluted olive oleine as raw material, 75% free fatty acids, the results show a strong increase in yield in the first two hours of reaction. The main products are FAMEs (87%) with some triglycerides. However, a residual 10% free fatty acid content is remained, and does not decrease with time. A final destillation should be performed to comply with the EU14214 european regulation for biodiesel specifications.
Time in hours
High Esterification Yield (%)
High FAME Yield (%)

10. PRODUCTION OF BIODIESEL FROM HIGH ACIDIC RAW MATERIALS
Design and development of an heterogeneous catalytic process
Discussion: Three phase heterogeneous process
FA + Sunflower oil (TG)
Methanol
Catalyst FA
FA + Methanol
FAME
Oil Phase
Water Phase
Why Fatty-Acid-Methyl-Esther Yields are higher in case of non diluted raw material. The explanation is the three phase heterogeneus nature of the process. Three phases: FA, methanol and catalyst must be put in contact and they are not miscible.
Using diluted raw material, FA are more miscible in sunflower oil (glycerides) than in methanol, so FA finally react with mono and diglycerides to produce triglycerides.
Using non diluted acidic raw materials, in abscence of glycerides, FA concentration in methanol is higher, so the evolution to FAME on the surface of catalyst is favoured, as can be seen in the right side of the picture.
DILUTED RAW MATERIAL
NON DILUTED
FA = Fatty Acid
FAME = Fatty Acid Methyl Ester
TG = Triglycerides

11. PRODUCTION OF BIODIESEL FROM HIGH ACIDIC RAW MATERIALS
Design and development of an heterogeneous catalytic process
Achievements
The production of biodiesel from non diluted oil industry wastes, in good yield, that commits with european legislation EU14214
Removal and valorization of a problematic waste
A new process for biodiesel production from high acidic raw materials, more friendly from an enviromental , safety and economic standpoint
To resume, three main achievements have been reached:
The production of biodiesel from non diluted oil industry acidic wastes, in good yield, that commits with EU14214
The removal and valorization of a problematic waste
The design and development of an innovative process for production of biodiesel from high acidic raw materials, more respectful with enviroment, in a safer and more profitable technology.

12. PRODUCTION OF BIODIESEL FROM HIGH ACIDIC RAW MATERIALS
Design and development of an heterogeneous catalytic process
Acknowledgements
Analysis and Characterization of products
To resume, three main achievements have been reached:
The production of biodiesel from non diluted oil industry acidic wastes, in good yield, that commits with EU14214
The removal and valorization of a problematic waste
The design and development of an innovative process for production of biodiesel from high acidic raw materials, more respectful with enviroment, in a safer and more profitable technology.
Design and construction of the Bench-Scale plant
Project suported under the program CIT by Ministery of Science and Innovation

13. PRODUCTION OF BIODIESEL FROM HIGH ACIDIC RAW MATERIALS
Design and development of an heterogeneous catalytic process
Thank you very much for your attention
To resume, three main achievements have been reached:
The production of biodiesel from non diluted oil industry acidic wastes, in good yield, that commits with EU14214
The removal and valorization of a problematic waste
The design and development of an innovative process for production of biodiesel from high acidic raw materials, more respectful with enviroment, in a safer and more profitable technology.

14. PRODUCTION OF BIODIESEL FROM HIGH ACIDIC RAW MATERIALS
Design and development of an heterogeneous catalytic process
Annex: EU14214 Biodiesel Specifications
Property
Unit
Test Method
Specification
Ester content
% (m/m) EN
96.5 min
Density at 15°C
kg/m3
EN ISO
860 – 900
Kinematic viscosity at 40°C
mm2/s
EN ISO
3.5 – 5.0
Flash point °C
EN ISO
101 min
Sulfur content
mg/kg
EN ISO
10 max
Carbon residue (on 10% distillation residue)
EN ISO
0.3 max
Cetane Number –
EN ISO 5165
51 min
Sulfated ash content
ISO
0.02 max
Water content
EN ISO
500 max
Total Contamination EN
24 max
Copper Strip Corrosion (3 hours at 50°C)
Rating
EN ISO
Class 1 max
Oxidation stability , 110°C (accelerated oxidation)
hours EN
6 min
Acid value
mg KOH/g EN
0.5 max
Iodine value
g iodine/100g EN
120 max
Linolenic acid methyl ester
12 max
Polyunsaturated (>= 4 Double bonds) methyl ester
EN 14103
1 max
Methanol content EN
0.2 max
Monoglyceride content EN
0.8 max
Diglyceride content
Triglyceride content
Free glycerine
Total glycerine
0.25 max
Group I metals (Na + K)
EN 14108/9
5 max
Group II metals (Ca + Mg)
EN 14538
Phosphorus content
EN 14107
4 max
Cold Filter Plugging Point
EN 116
+15 max