Biodiesel through membrane technology

Applied Energy, 2011

Renewable and Sustainable Energy Reviews, 2011

Biodiesel as a source of energy has been receiving great attention among the futurist and the world policy makers [1]. This is so because of its renewability, biodegradability, and better quality of exhaust gas emission [2]. The idea of vegetable oil based fuelto run diesel engines has been on the world stage over a century ago. The discovery of the potentials of vegetable oil to serve as fuel was made by one of the most famous scientist of the nineteenth century called "Rudolf Diesel". Rudolf Diesel, in 1912 stated that "the use of vegetable oils for engine fuels may seem insignificant today. But such oils may become in course of time as important as petroleum and the coal tar products of the present time" [3]. The interest to develop the technology of biodiesel fuel over the years was low due to availability and low cost petroleum products. The renewed and increasing interest in the growth and development of biodiesel fuel is driven mainly by its potentials to solve three main challenges confronting the global economy. These include among others: how to attain energy independence, reduce environmental impact and achieve fuel of affordable prices that can compete favorably with the conventional diesel fuel. Thus, biodiesel fuel in large quantities could be achieved if certain technologies are developed. Some of these technologies include: (1) Establishment of a scheme to generate low cost feedstocks. (2) Development of sound technology for the purification of crude biodiesel. (3) Development of good catalysts that can give higher yields of biodiesel with less refining difficulties. (4) Establishment of a sound policy that can improve the production of biodiesel fuels. (5) Exploration and exploitation of biodiesel production systems with the aim of minimizing energy and water use.

Biodiesel has drawn more and more attention in recent years because it is renewable and has less detrimental effects on environment as compared with conventional diesel derived from petroleum .It consists of mono alkyl esters that are usually produced by transesterification of plant or animal oil with alcohol in the presence of catalyst. Catalysts mainly belong to the categories of homogeneous or heterogeneous. Several processes for biodiesel fuel production have been developed, among which the transesterification using alkali catalysis gives high yields of conversion. The main problem of transesterification reaction is that the reactants are not readily miscible. This leads a longer reaction time and so higher fixed capital investments and product costs .Few other drawbacks of this traditional catalyzed batch methods include glycerin removal, and a need for removal of catalyst, in addition to soaps or other unwanted byproducts. In an effort to bypass these issues, some new processe...

Biodiesel has become more attractive recently because of its environmental bene®ts and the fact that it is made from renewable resources. The cost of biodiesel, however, is the main hurdle to commercialization of the product. The used cooking oils are used as raw material, adaption of continuous transesteri®cation process and recovery of high quality glycerol from biodiesel by-product (glycerol) are primary options to be considered to lower the cost of biodiesel. There are four primary ways to make biodiesel, direct use and blending, microemulsions, thermal cracking (pyrolysis) and transesteri®cation. The most commonly used method is transesteri®cation of vegetable oils and animal fats. The transesteri®cation reaction is aected by molar ratio of glycerides to alcohol, catalysts, reaction temperature, reaction time and free fatty acids and water content of oils or fats. The mechanism and kinetics of the transesteri®cation show how the reaction occurs and progresses. The processes of transesteri®cation and its downstream operations are also addressed. Ó : S 0 9 6 0 -8 5 2 4 ( 9 9 ) 0 0 0 2 5 -5

Biodiesel is a fuel with various benefits over the conventional diesel fuel. It is derived from renewable resources, it has less emission to environment, it is biodegradable so has very limited toxicity and above all its production can be decentralized so that it could have a potential in helping rural economies. However, there are also some worth mentioning challenges associated with production of biodiesel. Among them repeatedly mentioned are the cost of feedstock and the choice of convenient technology for efficient production of the fuel from diverse feedstock types. There are four main routes by which raw vegetable oil and/or animal fat can be made suitable for use as substituent fuel in diesel engines without modification. These are direct use or blending of oils, micro-emulsion, thermal cracking or pyrolysis and transesterification reaction. Due to the quality of the fuel produced, the transesterification method is the most preferred way to produce biodiesel from diverse feedstock types. Through this method, oils and fats (triglycerides) are converted to their alkyl esters with reduced viscosity to near diesel fuel levels. There are different techniques to carry out transesterification reaction for biodiesel production. Each technique has its own advantages and disadvantages as well as its own specifically convenient feedstock character. There are also some very important reaction conditions to be given due attention in each of this techniques for efficient production of biodiesel, such as molar ratio of alcohol to oil, type and amount of catalyst, reaction temperature, reaction time, reaction medium, type and relative amount of solvents, among others. This review is meant to investigate the main transesterification techniques for biodiesel production in terms of their choice of feedstock character as well as their determinately required reaction conditions for efficient biodiesel production, so that to give an overview on their advantages and disadvantages.

Bioresource technology, 1999

Biodiesel has become more attractive recently because of its environmental bene®ts and the fact that it is made from renewable resources. The cost of biodiesel, however, is the main hurdle to commercialization of the product. The used cooking oils are used as raw material, adaption of continuous transesteri®cation process and recovery of high quality glycerol from biodiesel by-product (glycerol) are primary options to be considered to lower the cost of biodiesel. There are four primary ways to make biodiesel, direct use and blending, microemulsions, thermal cracking (pyrolysis) and transesteri®cation. The most commonly used method is transesteri®cation of vegetable oils and animal fats. The transesteri®cation reaction is aected by molar ratio of glycerides to alcohol, catalysts, reaction temperature, reaction time and free fatty acids and water content of oils or fats. The mechanism and kinetics of the transesteri®cation show how the reaction occurs and progresses. The processes of transesteri®cation and its downstream operations are also addressed. Ó : S 0 9 6 0 -8 5 2 4 ( 9 9 ) 0 0 0 2 5 -5

Catalysts

Biodiesel, comprising mono alkyl fatty acid esters or methyl ethyl esters, is an encouraging option to fossil fuels or diesel produced from petroleum; it has comparable characteristics and its use has the potential to diminish carbon dioxide production and greenhouse gas emissions. Manufactured from recyclable and sustainable feedstocks, e.g., oils originating from vegetation, biodiesel has biodegradable properties and has no toxic impact on ecosystems. The evolution of biodiesel has been precipitated by the continuing environmental damage created by the deployment of fossil fuels. Biodiesel is predominantly synthesised via transesterification and esterification procedures. These involve a number of key constituents, i.e., the feedstock and catalytic agent, the proportion of methanol to oil, the circumstances of the reaction and the product segregation and purification processes. Elements that influence the yield and standard of the obtained biodiesel encompass the form and quantity...

CHEMTAG Journal of Chemical Engineering

Biodiesel is a potential renewable energy that can reduce greenhouse gas (GHG) emissions and increase energy security. Biodiesel has been shown to have lower carbon emissions compared to petroleum diesel, and it can reduce GHG by as much as 86%. Governments around the world have set targets for renewable energy, with a specific focus on the use of biofuels like biodiesel. Biodiesel can be derived from various feedstocks such as animal lipids, vegetable oils, and waste oils. It can be made through the transesterification of triglyceride with ethanol or methanol. This reaction requires strong base catalysts, such as sodium hydroxide or potassium hydroxide, in order to produce methyl esters. The potential of biodiesel has led to advancements in its production, such as the use of enzymatic transesterification, novel feedstocks, and the optimization of production parameters. Additionally, various companies have ventured into biodiesel production with a range of business models and approaches.

International Journal of Environmental Studies, 2012

journal of Chilean chemical society, 2021

Biodiesel is a long-chain fatty acid ester made from renewed and biological raw materials such as used cooking, animal fat, vegetable oil, and algae. Biodiesel is a renewable and clean fuel as it reduces carbon monoxide, carbon dioxide, hydrocarbons, and particulate matter emissions compared with petroleum-based diesel fuel. Production of biodiesel from renewable resources is done through the transesterification reaction at which the organic group (alkyl) of alcohol is substituted with the organic group of a triglyceride-the main component of the feedstock-producing fatty acid alkyl ester (biodiesel) and crude glycerol. Biodiesel can be used in pure form (B100) or may be blended with petroleum diesel at any concentration if its specifications is identical to the international standard specifications provided by American standard for testing materials (ASTM) or EN14214 in the European Union for alternative fuels. In this paper, the different types of biodiesel feedstocks, feedstocks treatment methods, and biodiesel production technologies are reviewed and discussed.