More Efficient Biodiesel More Efficient Biodiesel ProductionProduction

Adam HarveyAdam HarveyProcess Intensification Group [PIG]Process Intensification Group [PIG]School of Chemical Engineering & Advanced School of Chemical Engineering & Advanced

MaterialsMaterialsNewcastle University Newcastle University

What is Biodiesel??What is Biodiesel??Methyl ester produced by reacting vegetable oils (triglycerides) Methyl ester produced by reacting vegetable oils (triglycerides)

with methanol. This requires a basic catalyst (usually NaOH).with methanol. This requires a basic catalyst (usually NaOH).

+ 3 MeOH

CH2

CH

CH2

COO

COO

COO

Triglyceride (vegetable oil)

+

CH2

CH

CH2

HO

HO

HO

Glycerol

COOCH3

Biodiesel

(FAME)x 3 Lower Viscosity

Cleaner Burning

Catalyst

Why should/will biodiesel be Why should/will biodiesel be used?used?

1.1. RENEWABLERENEWABLE2.2. REDUCED LIFECYCLE CARBON DIOXIDE EMISSIONREDUCED LIFECYCLE CARBON DIOXIDE EMISSION3.3. REDUCED POLLUTION:REDUCED POLLUTION:

1.1. Particulates!!Particulates!!2.2. Carbon monoxideCarbon monoxide3.3. HydrocarbonsHydrocarbons4.4. Sulphur compoundsSulphur compounds

4.4. Immediate effect: distribution network and Immediate effect: distribution network and engines are already in placeengines are already in place

5.5. As a use for waste oilsAs a use for waste oils6.6. Security of supplySecurity of supply7.7. Increased lubricity: increases engine lifetimeIncreased lubricity: increases engine lifetime8.8. Non-toxicNon-toxic9.9. BiodegradableBiodegradable

Project 1: Design of Intensified Project 1: Design of Intensified Biodiesel PlantsBiodiesel Plants

Based on an “intensified” continuous reactor, known as the oscillatory flow reactor [OFR]

Commercial project: development of a portable biodiesel plant: • Use in developing countries where supply of transport

fuels can be unreliable: • Farmers producing their own transport fuel: an example

of “distributed production”

Demonstrator currently being fabricated.

Further development of OFR for biodiesel to start soon.

Intensified, Portable Intensified, Portable Biodiesel PlantBiodiesel Plant

Vegetable Oil

Methanol+ Catalyst

REACTOR SETTLER

GlycerolTank

Flash

DRY POLISH

BIODIESELTANK

Portable Unit

glycerol

Process Intensification:Process Intensification:The Oscillatory Flow ReactorThe Oscillatory Flow Reactor

15 minutes < 2h

Niche Application of the Niche Application of the OFROFR

• • length/diameter ratio much smaller than length/diameter ratio much smaller than equivalent conventional PFRequivalent conventional PFR

• • plug flow RTDplug flow RTD

• • effective two phase mixing of liquidseffective two phase mixing of liquids

Conversion of long residence time Conversion of long residence time batch processes to continuous batch processes to continuous

processesprocesses

Initial Dispersion

Injection point

Net flow

Net Flow InNet FlowOut

Reaction’s Progressalong Reactor

Commercial Demonstration PlantCommercial Demonstration Plant

Project 2: Solid Catalysts for Project 2: Solid Catalysts for BiodieselBiodiesel

1. Reduce capital costs of biodiesel plants 2. Reduced running costs 3. Reduced waste (soap)4. Reduce glycerol purification costs

waste water, soap

Oil

Methanol

Catalyst

glycerol & methanol

Reactor

water washing, dry, polish etc

Flash

biodiesel

Methanol recycle

Neutralisation

salt glycerolCurrent Process

Oil

MethanolFlash

biodiesel

Methanol recycle

glycerol

Separation of catalyst from product via simple - filter

Reactor

Biodiesel Process using Solid Catalyst

Solid Catalysts Solid Catalysts (requirements)(requirements)

Robust (long lifetime) Active (2h reaction time or less) Inexpensive Available in bulk quantities Easy to manufacture Stable

Solid CatalystsSolid Catalysts Alkaline earth metal oxide substrates, doped with

alkali metals, e.g.:– LiCaO– LiMgO– KCaO– KMgO

Problem 1i. Solubility of substrateii. Leaching of catalyst

Project 3: Biodiesel Directly from Project 3: Biodiesel Directly from Seed: Seed:

“Combined Extraction and “Combined Extraction and Reaction”Reaction”

• Would facilitate distributed production• Successful demonstration for rapeseed

solvent extraction

+ reaction

Alcohols + Catalyst

BiodieselGlycerol

Meal

Oilseeds

Conventional Biodiesel Conventional Biodiesel ProductionProduction

1. Farm

2. Oil Extraction

3. Conversion to Biodiesel

Oilseed Growing

Crushing

Oilseeds

Solvent Extraction

Vegetable Oil

Hexane

Meal Meal

ReactorMethanol+ Catalyst

DownstreamProcessing

Glycerol

BiodieselBiodiesel

Distributed Biodiesel Distributed Biodiesel ProductionProduction

1. Farm Oilseed Growing

ReactorMethanol+ Catalyst

DownstreamProcessing Glycerol

BiodieselBiodiesel

Oilseed Cracking

Meal

Reactive ExtractionReactive Extraction

Successfully produced biodiesel Successfully produced biodiesel directly from rapeseeds and jatropha directly from rapeseeds and jatropha nutsnuts

Now optimising the processNow optimising the process Downstream separation studies have Downstream separation studies have

begunbegun

Other Biodiesel ProjectsOther Biodiesel Projects

1.1. Biodiesel from Algae: design of Biodiesel from Algae: design of photobioreactors and whole process photobioreactors and whole process

2.2. Triglyceride cracking to produce Triglyceride cracking to produce biodieselbiodiesel

3.3. Biodiesel from jatropha (reactive Biodiesel from jatropha (reactive extraction using solid catalysts)extraction using solid catalysts)

4.4. Study of cold flow propertiesStudy of cold flow properties

AcknowledgmentsAcknowledgments

Dr Jonathan Lee, CEAM, NewcastleDr Jonathan Lee, CEAM, Newcastle PhD StudentsPhD Students Research exchange studentsResearch exchange students Masters research studentsMasters research students

What about the Glycerol?What about the Glycerol?~15% (volume) of the total output

of a biodiesel reaction is (impure) glycerol.

What should be done with it?

• Cosmetics industry?• Energy?• “Renewable chemicals”:

Propylene glycol, methanol, lactic acid, propane-1,3-diol, epichlorohydrin etc

“Glycerochemistry”

1.1.FlowFlow2.2.Burning characteristics:Burning characteristics:

1.1.Trumpet FormationTrumpet Formation2.2.Lacquer FormationLacquer Formation

3.3.Pollution: acrolein formation (a.k.a. 2-Pollution: acrolein formation (a.k.a. 2-propenal)propenal)

“Acrolein is such a severe pulmonary irritant and lacrimating agent that it has been used as a chemical weapon during

World War I.” & “suspected human carcinogen.”

Why not burn the fats/oils directlyWhy not burn the fats/oils directly??