Transesterification is a reaction of triglycerides with or without catalyst which removes glycerol and replaces of short chain alcohol. The properties like cetane number and heating value are well maintained whereas viscosity, long carbon chain and density are reduced during the process of transesterification. A lot of research have been carried in the field of operating parameters for transesterification reaction which includes the reaction temperature, the type and amount of catalyst, the ratio of alcohol to oil, the mixing intensity and the reaction time. The choice of catalyst in transesterification reaction influences the complexity of the downstream separation and purification unit operations resulting direct impact on techno-economics …show more content…
Other than catalytic method, supercritical method is used where the thermal decomposition of fatty acid chains takes place at high pressure and temperature. There have been a lot of review work on biodiesel focusing various feedstocks and reaction conditions but the work considering the entire separation and purification steps is scare. It is important to study the recent biodiesel production techniques via transesterification and its influence on downstream unit operations before reviewing the separation and purification of crude …show more content…
Supercritical transesterification deals with severe reaction condition but the downstream separation and purification steps are simple and the large number of equipment requirement is less compared to other production techniques. Recently a supercritical process for biodiesel production using Jatropha is reported to yield 99.5 % biodiesel for oil to methanol molar ratio 1:42 at 35 MPa pressure and 325°C temperature [41]. Many researchers have used non-catalyzed supercritical process for non-edible Jatropha oil with oil to methanol molar ratio 1:43, 8.4 MPa pressure, reaction temperature 593K and reaction time of 4 minutes yielding 100% biodiesel [42] and the other with oil to methanol molar ratio 1:40, 15MPa pressure, reaction temperature 593K and reaction time of 5 minutes yielding 84.6% [43]. None [42-43] of them discussed separation and purification steps in biodiesel production. It is reported that the co-solvent play an active role in increasing the mutual solubility of methanol and oil at low reaction temperatures at supercritical conditions [27, 44]. Alcohol recovery is an important operation as a large amount is poured during reaction process oil. It is observed that the supercritical process requires a high operating condition for transesterification reaction and high oil to methanol ratio. Though the supercritical process has an
The most classic and standard procedure for producing esters is the Fisher-esterification reaction. Discovered in 1895 by German chemists Emil Fischer and Arthur Speier 4, this reaction involves refluxing a carboxylic acid and an alcohol in the presence of an acid catalyst. In order to drive the equilibrium towards the products, the water from the dehydration process must be removed and there must be an excess amount of alcohol. A vast range of carboxylic acids may be used for this reaction however the type of alcohols are limited. Primary and secondary alcohols are most frequently used in esterification reactions, tertiary alcohols are steric ally hindered usually resulting in poor yields5 and tend to undergo elimination reactions instead. In this rea...
Biodiesel is produced by subjecting the triglycerides found in vegetables oils and fats to transesterification, which is the exchanging of the alkoxy group of an ester compound by another alcohol. This creates an ox...
Esterification is the process of forming ester between an acid and an alcohol. The acid in this process can be an organic acid such as carboxylic acid or an inorganic acid such as sulfuric acid. Using excess acid or alcohol and removing water are the ways to shift the equilibrium towards the products. Using excess acid or removing water distract the equilibrium so that more product forms to make the equilibrium repeatedly. In this lab, carboxylic acid and methanol were used as esterification reaction. Methanol is a good solvent treated with heat because it gives the most rapid reaction and the highest yield. The analytical methods used are melting point, IR, and TLC. Melting point decided with solids and different rf values and IR spectrum was shown due to composition change.
In spite of, some people thinking that biodiesel have further disadvantages than advantages others respectably disagree. Supporters of biodiesel have faith in biodiesel being worthy substitutes of diesel fuel since it can help improve the environment. “According to the Environmental Protection Agency (EPA), greenhouse gas emissions can be reduced by at least by 57 percent and up to 86 percent with the use of biodiesel” (“What is Biodiesel?”).
In 1960 Oswald and Golweke proposed the use of large‐scale ponds for cultivating algae on wastewater nutrients and anaerobically fermenting the biomass into methane fuel. Algae, like all bio fuels, harvests the energy from water and sunlight to produce oil which can be converted into biodiesel as well as the carbohydrate content to be fermented into ethanol (Benemann, Olst, et al. 1). The concept of using vegetal oil as an engine fuel likely dates back to when Rudolf Diesel (1858‐1913) developed the first engine to run on peanut oil, as he demonstrated at the World Exhibition in Paris in 1900 (Biodiesel 1). Using algae, however, is only a very recent concept as the first algae biodiesel plant only opened this year on April 1, 2008. The company, PetroSun, is expected to produce ≈4.4 million gallons of algal oil and 110 million lbs of biomass per year in their 1,000 acres. Fuel will not be produced immediately, but they will be building or acquiring ethanol and biodiesel production plants in the near future (Cornell 1).
The main focus of the lab is the transesterification process, and biodiesel transportation fuel. The transesterification process is a process in organic chemistry where the alkoxy group of an ester compound is exchanged by another alcohol. The triglycerides react with an alcohol to from the esters and glycerol in a transesterification reaction. Oil is converted to biodiesel fuel using transesterification. Biodiesel fuels are liquid fuels that are produced from the oils. Biodiesel fuel
Coconut oil was used to be an alternative to biodiesel in Thailand. The researchers found out that coconut oil has 12.8% of free fatty acid (FFA) that is possible to be used as a biodiesel through a series of process. First is that they reduced the FFA through acid-catalyzed esterification. In the second step they used the product produced in the first step and was transesterified with methanol to produce a biodiesel product. Moreover, they found out that the coconut oil biodiesel and the Thai petroleum was very much the same.
The continuous depletion of fossil fuel resources and their increased demand has changed the outlook from ancient resources of fuel to new resources especially biomasses of plant origin. Plant biomass is a promising raw material for fuel generation to sustain fuel requirements in the modern age. Basically biofuel these days can be divided into first generation and second generation depending upon the type of biomass used. Biofuel derived from sugars, oils, cereals, sugarcane and starch are categorised in first generation fuel while use of lignocellulosic biomass like soft and hardwood, agricultural wastes, straw and corn stover provides second generation fuels [1].
Base catalysts are highly sensitive to water content due to soap formation which makes separation difficult. Acid catalyst are used when the acid values of the non-edible oils are higher than the performance range of base catalysts. The acid value represents the number of acidic functional groups and is measured in terms of the quantity of potassium hydroxide required to neutralize the acidic characteristics of the sample. The protonation of the carbonyl group of the ester promotes the formation of a carbocation, which after nucleophilic attack of the alcohol produces a tetrahedral intermediate. This intermediate will eliminate glycerol to form a new ester and to reform the catalyst. Acid-catalyzed transesterification are carried out in the absence of water. The problems with the use of these catalysts are: the requirement for more alcohol; slower reaction rates; higher reaction temperatures and pressures; reactor corrosion and environmental issues. Both homogeneous and heterogonous acid catalysts can be used for transesterification. The acid catalysts more commonly used include, sulfuric acid, hydrochloric acid, phosphoric acid, and sulfonated organic acids. Due to the fact that the FFA content of neat edible oils is normally low but these oils are costly and conversion of too much edible oil into biodiesel may cause food crises, use
Biomass gasification is a process by which biofuel is produced. It has been used for over 180 years but in the last decades it has been reconsidered as an interesting technique due to the fact that oil supplies are decreasing. As mentioned before, gasification is a thermal process. Heat is added up in order to convert the organic mass to biofuel. The biomass usually undergoes drying, pyrolysis, partial oxidation and reduction. Nowadays the configurations used for gasification are three: fixed bed gasifier, fluidized bed gasifier and entrained bed gasifiers. The simplest configuration is the
Biodiesel is made by integrating vegetable fat, oil animal, or recycled cooking greases with alcohol (usually metha...
Bioreactor is one of the most familiar words in bioprocessing engineering's books. Which mean a place which is designed to be suitable for the growth of specific types of bacteria, fungi or other microorganisms by provision of the necessary conditions for its growth [2]. These microorganisms are doing biochemical processes that produce useful materials for humanity, Such as some kinds of medicines, enzymes and fuel. In this case the fuel which made by microorganisms is called bio fuel [3]. Bio fuel often is environmentally friendly, and has many advantages such as it is cheap, it is a renewable power resource and it is product able easily. On the other side it has some negative point such as it need a lot of time to make few litter of bio fuel when we use the normal method to produce it. In this project some points of designing devices, methods and technology of bioreactors and using it to producing bio fuel will be discussed.
Coal and crude oil are non-renewable resources. They take an extreme amount of time to form and due to that, they cannot be replaced once they have all been used up. However, when it comes to the biofuels, they are produced from plant material and are renewable. There are two types of biofuels: Biodiesel, which is made from rapeseed oil and other plant oils and is used in diesel-powered vehicles without needing any modifications to the engine, and Bioethanol, which is a liquid fuel that burns quite well and is made by fermenting sugars from sugar cane, wheat and other plants. In this essay, whether or not biofuels are becoming an increasingly important alternative to traditional forms of energy under environmental and economic benefits and
Supercritical fluids are involved in numerous industrial processes especially food industry and have a potentially wide field of new applications. The current applications of supercritical fluid include extraction processes, reaction chemistry and polymerization, food fractionation, waste recycling, soil remediation, cleaning of electronic and optical equipment parts, impregnation, dry powder coating, aerogels, nanotechnology, and crystallization and particle formation of pharmaceuticals and many other powdered products. In food industry, the most commonly use are in rapid analysis for fat content, rapid analysis for pesticides in foods, detection of food pollutants, encapsulation of liquids for engineering solid products, removal of alcohol
The mixture of bio-oil (40 g) and ethanol (10 g) was placed with amberlyst 36 resin into the autoclave reactor (200 mL SUS316). The reactor was sealed and flushed three times with N2. After that, the reaction was performed at under mild temperature conditions (50, 100, or 150 °C) under 3 MPa H2 pressure. After the resin