Advances in Catalytic Technologies for Biodiesel Fuel Synthesis

The greenhouse effect and its consequences are a growing concern for humanity [...

Noncatalytic Biodiesel Synthesis under Supercritical Conditions

The constant increase in greenhouse gases in the environment is forcing people to look for different ways to reduce such pollution. One of these ways is the use of biodiesel for road transport. Conventional biodiesel production involves the catalytic triglyceride transesterification process. When using homogeneous two-stage catalysis, it is difficult to purify the resulting product from the by-products formed, and the catalysts cannot be reused. In the case of heterogeneous catalysis, the process costs are increased due to separation and regeneration of the catalysts. To solve these problems of catalytic synthesis, a noncatalytic process has been recently studied that which takes place under supercritical conditions for an alcohol or other acyl receptor. In such biodiesel production, fatty feedstocks and alcohols are used as raw materials, with the synthesis taking place at supercritical conditions for alcohol, i.e., high temperature and pressure, thus making the process quite simple. This paper reviews the results obtained from biodiesel synthesis using a noncatalytic supercritical process for transesterification using both alcohols and carboxylate esters of low molecular weight, evaluating the optimal conditions for these processes and biofuel stability at high temperatures

Application of Microalgae Biomass for Biodiesel Fuel Production

Recently, there has been a growing interest in the use of new types of cheaper raw materials for biodiesel production. There are many prospects for microalgae, which do not compete for land with conventional biodiesel raw materials, are characterized by rapid reproduction and high biomass accumulation, and under certain conditions, some are able to accumulate a large amount of oil. A number of studies have been conducted on the extraction of oil from microalgae cells and transesterification with various acyl receptors. This paper provides an overview of the results of research on microalgal biomass preparation and oil extraction. Indicators of the quality of the oil are presented and its suitability for biodiesel synthesis is analyzed. The homogeneous and heterogeneous catalysts used for oil transesterification are described and the optimal conditions of the process when using various alcohols as acyl receptors are presented. Much attention is paid to the parameters affecting the transesterification efficiency and biodiesel yield. The physical and chemical, and operational and environmental properties of biodiesel obtained from algae oil are analyzed. The evaluation of the economic efficiency of biodiesel synthesis is also presented

Synthesis of Biodiesel by Interesterification of Triglycerides with Methyl Formate

In the conventional synthesis of biodiesel, not only fatty acid esters (biodiesel) are formed, but also the by-product is the glycerol phase, which amounts to about 10 wt.%. Recently, the studies on the interesterification of oil using carboxylate esters have been launched. In this case, no glycerol is formed, and esters of glycerol and short-chain organic acids soluble in biodiesel are produced. The biodiesel yield is increased, and the biodiesel production process is more economically viable. The process of interesterification with methyl formate yields a mixture of biodiesel and triformylglycerol, which is not inferior in quality to biodiesel, but also has better low-temperature properties. The paper analyzes the application of chemical and enzymatic catalysis methods for the interesterification of triglycerides with methyl formate. The influence of catalyst amount, reagent molar ratio, temperature, and process time on the product yield is presented. The quality indicators of the obtained fuel and their compliance with the requirements of the biodiesel fuel standard are discussed

GREEN ENERGY FROM MICROALGAE: USAGE OF ALGAE BIOMASS FOR ANAEROBIC DIGESTION

The microalgae biomass can be used for various types of biofuels, including biodiesel and biogas. The aim of this study is to investigate the possibilities of microalgae Scenedesmus sp. and Chlorella sp. (widespread in freshwater Lithuanian lakes) usage for biogas production. Microalgae were cultivated under mixotrophic conditions (growth medium BG11containing technical glycerol). In order to determine biogas yield and quality dependence on feedstock preparation, the analyses of biogas production have been performed with algae biomass prepared in different ways: wet centrifuged; wet centrifuged, frozen and defrost; dry not de-oiled and dry de-oiled. The highest biogas yield in both cases (Scenedesmus sp. – 646 ml/gDM and Chlorella sp. – 652 ml/gDM) was obtained from centrifuged, frozen and defrost biomass. Biogas yield was app. 1.46 times higher comparing to yield of biogas produced from wastewater sludge. Our results showed that different types of biomass preparation have no significant influence on quality of biogas

Synthesis of Biodiesel by Interesterification of Triglycerides with Methyl Formate

In the conventional synthesis of biodiesel, not only fatty acid esters (biodiesel) are formed, but also the by-product is the glycerol phase, which amounts to about 10 wt.%. Recently, the studies on the interesterification of oil using carboxylate esters have been launched. In this case, no glycerol is formed, and esters of glycerol and short-chain organic acids soluble in biodiesel are produced. The biodiesel yield is increased, and the biodiesel production process is more economically viable. The process of interesterification with methyl formate yields a mixture of biodiesel and triformylglycerol, which is not inferior in quality to biodiesel, but also has better low-temperature properties. The paper analyzes the application of chemical and enzymatic catalysis methods for the interesterification of triglycerides with methyl formate. The influence of catalyst amount, reagent molar ratio, temperature, and process time on the product yield is presented. The quality indicators of the obtained fuel and their compliance with the requirements of the biodiesel fuel standard are discussed

Application of Liquid Waste from Biogas Production for Microalgae <i>Chlorella</i> sp. Cultivation

Microalgae biomass is a viable feedstock for a wide range of industries. Recently, there has also been interest in the ability of microalgae biomass applications for biofuel production. In the meantime, the cultivation of microalgae biomass requires high energy costs, and the application of microalgae for technical purposes is still problematic. A significant part of the cost of biomass arises from the nutrients used for cultivation. Chemical compounds included in the microalgae cultivation media can be replaced by suitable wastes containing nitrogen, phosphorus, and other elements. This could reduce the microalgae biomass cultivation price and allow cheaper biomass to be used for biofuel production. The aim of this work was to comprehensively investigate and optimize the growth process of microalgae using liquid waste (liquid waste after biogas production from sewage sludge and distillers’ grain) as a source of nitrogen and phosphorus, and technical glycerol as a carbon source. It was found that higher levels of waste in the cultivation media were found to inhibit the accumulation of microalgal biomass, with the optimum level corresponding to a nitrogen concentration of 0.08 g/L. The influence of technical glycerol from biodiesel production on the yield of microalgal biomass was investigated, and it was found that the addition of 6% glycerol allows an increase in the concentration of microalgal biomass in the cultivation media, from 18.1 to 20.6%

Analysis of Biological Degradation and Life Cycle Indicators of Mineral Diesel Fuel Mixtures, Containing 10% Biodiesel, Obtained by Simultaneous Oil Extraction and Transesterification

This article provides data on the environmental properties of biofuels obtained by the simultaneous extraction of oil from spoiled rapeseed and transesterification, with the addition of mineral diesel to the reaction mixture. The resulting reaction product contained 10% biodiesel: fatty acid methyl, ethyl, or butyl esters in mixtures with mineral diesel. The addition of biodiesel has been found to increase the rate of biodegradation of fuels. Such fuels are classified as partially biodegradable, according to the OECD classification. Life cycle analysis showed that the mixtures of biodiesel and mineral diesel have lower negative environmental impacts, compared to pure mineral diesel. The values of indicators such as abiotic depletion, acidification, global warming, ozone depletion, and human toxicity for these mixtures were 40–58% lower compared to the corresponding values for mineral diesel

INTERESTERIFICATION OF RAPESEED OIL WITH METHYL FORMATE FOR PRODUCTION OF INNOVATIVE BIODIESEL FUEL

During the production of biodiesel, a by-product - the glycerol phase is formed (about 10% of the obtained biodiesel). The interesterification of vegetable oil using carboxylate esters of low molecular weight does not produce glycerol, instead its compounds (mono-, di- and triformyl glycerides) are obtained in a mixture with fatty acid alkyl esters (conventional biodiesel). Such a product can be used as fuel for diesel engines. The aim of the work was to investigate the possibilities of application of methyl formate in the biotechnological production of biodiesel. The industrial enzyme preparation Lipozyme TL IM was used as a catalyst for interesterification. The influence of the amount of catalyst, the molar ratio of methyl formate to oil and the duration of the process on the yield of biodiesel was evaluated. The highest yield of rapeseed oil methyl esters was obtained under the following conditions: 14-15% of the enzyme preparation Lipozyme TL IM (based on the weight of the oil), molar ratio of methyl formate to oil - 40:1, duration - 60 h. Under these conditions, an 81.6% yield of rapeseed oil methyl esters was obtained

Effectiveness of Eggshells as Natural Heterogeneous Catalysts for Transesterification of Rapeseed Oil with Methanol

Heterogeneous catalysis has an advantage of easy separation of the catalyst after biodiesel is produced. CaO is known to be an efficient heterogeneous catalyst for biodiesel production. Taking into account that CaO is a key component of eggshells, the effectiveness of eggshells as a heterogeneous catalyst for rapeseed oil transesterification with methanol was investigated and optimal conditions of biodiesel production were determined applying RSM methodology. The influence of three independent variables on ester content was analyzed and a quadratic model was created. It was determined that this model is statistically significant. The optimum transesterification conditions when eggshells are used as a heterogeneous catalyst, and the process temperature of 64 &deg;C, were determined as: the methanol-to-oil molar ratio 10.93:1; the catalyst amount 6.80 wt%; the reaction duration 9.48 h. The ester yield of 97.79 wt% was obtained under these conditions