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More Efficient Biodiesel Production. Adam Harvey Process Intensification Group [PIG] School of Chemical Engineering & Advanced Materials Newcastle University. HO. CH 2. +. COOCH 3. CH. HO. Biodiesel (FAME). x 3. HO. CH 2. Glycerol. What is Biodiesel??.
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More Efficient Biodiesel Production Adam Harvey Process Intensification Group [PIG] School of Chemical Engineering & Advanced Materials Newcastle University
HO CH2 + COOCH3 CH HO Biodiesel (FAME) x 3 HO CH2 Glycerol What is Biodiesel?? Methyl ester produced by reacting vegetable oils (triglycerides) with methanol. This requires a basic catalyst (usually NaOH). Triglyceride (vegetable oil) COO CH2 COO + 3 MeOH CH CH2 COO Catalyst Lower Viscosity Cleaner Burning
Why should/will biodiesel be used? • RENEWABLE • REDUCED LIFECYCLE CARBON DIOXIDE EMISSION • REDUCED POLLUTION: • Particulates!! • Carbon monoxide • Hydrocarbons • Sulphur compounds • Immediate effect: distribution network and engines are already in place • As a use for waste oils • Security of supply • Increased lubricity: increases engine lifetime • Non-toxic • Biodegradable
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. Project 1: Design of Intensified Biodiesel Plants
Intensified, Portable Biodiesel Plant Methanol + Catalyst Vegetable Oil Portable Unit REACTOR SETTLER DRY POLISH glycerol Flash Glycerol Tank BIODIESEL TANK
Process Intensification:The Oscillatory Flow Reactor 15 minutes < 2h
Niche Application of the OFR Conversion of long residence time batch processes to continuous processes • length/diameter ratio much smaller than equivalent conventional PFR • plug flow RTD • effective two phase mixing of liquids
Net flow Initial Dispersion Injection point
Reaction’s Progress along Reactor Net Flow Out Net Flow In
Project 2: Solid Catalysts for Biodiesel • Reduce capital costs of biodiesel plants • Reduced running costs • Reduced waste (soap) • Reduce glycerol purification costs waste water, soap water washing, dry, polish etc Oil Methanol Reactor biodiesel Catalyst Flash Neutralisation glycerol & methanol Current Process salt glycerol Methanol recycle
Biodiesel Process using Solid Catalyst Oil Methanol biodiesel Flash Reactor glycerol Methanol recycle Separation of catalyst from product via simple - filter
Solid Catalysts (requirements) • Robust (long lifetime) • Active (2h reaction time or less) • Inexpensive • Available in bulk quantities • Easy to manufacture • Stable
Solid Catalysts • Alkaline earth metal oxide substrates, doped with alkali metals, e.g.: • LiCaO • LiMgO • KCaO • KMgO Problem 1 • Solubility of substrate • Leaching of catalyst
Project 3: Biodiesel Directly from Seed: “Combined Extraction and Reaction” Alcohols + Catalyst Biodiesel solvent extraction + reaction Glycerol Oilseeds Meal • Would facilitate distributed production • Successful demonstration for rapeseed
Conventional Biodiesel Production Oilseed Growing 1. Farm Oilseeds Hexane 2. Oil Extraction Solvent Extraction Crushing Meal Meal Vegetable Oil 3. Conversion to Biodiesel Downstream Processing Reactor Methanol + Catalyst Biodiesel Glycerol
Distributed Biodiesel Production Oilseed Growing 1. Farm Oilseed Cracking Reactor Methanol + Catalyst Meal Downstream Processing Glycerol Biodiesel
Reactive Extraction • Successfully produced biodiesel directly from rapeseeds and jatropha nuts • Now optimising the process • Downstream separation studies have begun
Other Biodiesel Projects • Biodiesel from Algae: design of photobioreactors and whole process • Triglyceride cracking to produce biodiesel • Biodiesel from jatropha (reactive extraction using solid catalysts) • Study of cold flow properties
Acknowledgments • Dr Jonathan Lee, CEAM, Newcastle • PhD Students • Research exchange students • Masters research students
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”
Why not burn the fats/oils directly? • Flow • Burning characteristics: • Trumpet Formation • Lacquer Formation • Pollution: acrolein formation (a.k.a. 2-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 humancarcinogen.”