* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Improvements & new technologies
Survey
Document related concepts
Cracking (chemistry) wikipedia , lookup
Kinetic resolution wikipedia , lookup
Enantioselective synthesis wikipedia , lookup
Ring-closing metathesis wikipedia , lookup
Marcus theory wikipedia , lookup
Physical organic chemistry wikipedia , lookup
George S. Hammond wikipedia , lookup
Fischer–Tropsch process wikipedia , lookup
Ene reaction wikipedia , lookup
Hofmann–Löffler reaction wikipedia , lookup
Baylis–Hillman reaction wikipedia , lookup
Petasis reaction wikipedia , lookup
Transcript
Raúl Mateos González Katharina J. Bauer Pablo M. Martín Soladana Content Definition Chemical reaction Comparison to conventional diesel Homogeneous and heterogeneous catalysis Improvement and new technologies Conclusion INTRODUCTION Definition: Biodiesel is defined as fatty acid methyl or ethyl esters from vegetable oils or animal fats when they are used as fuel in diesel engines and heating systems. CHEMICAL REACTION Transesterification catalyzed by acid or basic homogeneous catalysts with alcohol SAPONIFICATION Occurs when FFA react with basic catalyst Problematic because: Consume catalyst Biodiesel yield decreases Complicates separation & purification reduce biodiesel production efficiency COMPARISON BIODIESEL VS. CONVENTIONAL DIESEL Biodiesel advantages Independency from crude oil imports Less harmful emissions Biodegradable and non-toxic Safer to store and transport Biodiesel disadvantages Higher production costs Raw material problems HOMOGENEOUS & HETEROGENEOUS Advantages of heterogeneous process: •Lower initial costs •High conversion rate •Less chemicals are used •Lower consumption of methanol •Glycerine is purer Advantages of homogeneous process: •Biodiesel does not depend on glycerine price •Lower consumption of energy is needed Homogeneous catalysis Base catalyzed reaction: •It is able to catalyze reactions at low temperature and atmospheric pressure. •High conversion can be achieved in minimal time •Economical Although is very sensible to FFA on the feedstock. Homogeneous catalysis Acid catalyzed reaction: •Insensitive to FFA in feedstock •H2SO4 and HCl is used •More economical process •Although lower reaction rate Homogeneous catalysis Homogeneous acid and basic catalyst: •FFA can be converted to ester •A lot of acid is required to esterification IMPROVEMENTS & NEW TECHNOLOGIES 1. Enzymatic catalysis 2. Microwaves 3. Ultrasonic technology ENZYMES Advantages: • Produces less wastewater Disadvantages: • Expensive catalysis • No by-products • Industrial scale • Mild reaction conditions • Slow reaction rate • Easy separation • Enzyme deactivation and degeneration • Reutilization ENZYMES Mostly used enzymes: • Lypozym IM 60: Good yields with primary alcohols (93-99%) Deactivation can be avoided using hexane as solvent •PS 30 Better with secondary alcohols (85%) Used with hexane as solvent Immobilization (easy recovery) •Novozym 435 Best with secondary alcohols (96%) No solvent is used Deactivation problems MICROWAVES • Temperature stability • Reduces reaction time • Improves efficiency • Expensive equipment • Continuous process improvement ULTRASONIC TECHNOLOGY • Stirring method • Energy efficiency •Useful for less solvable substances • Reduces biodiesel and glycerol adsorption to equipment Conclusion Homogeneous catalysis is the most commonly used method Saponification is the main problem New technologies need to be improved