Centrifugation, filtration or magnetic extraction: Evaluation of catalyst recovery technique in biodiesel production

Recent trends of biodiesel production from animal fat wastes and associated production techniques

Biodiesel has the potential to contribute significantly to the elimination of the present global energy and climate change logjam, but its production and commercialization have been hindered by the diverse nature of the feedstocks used for production. This paper reviews the effectiveness of applying various types of crop and animal waste‐derived catalysts together with innovative feedstock hybridization as an economically viable technique for biodiesel production. Feedstock challenges, availability, and sustainability for large‐scale applications are addressed with a view to bridging the existing gaps. Challenges in the use of edible oils and algae oil sources and development remain, but the technique of feedstock hybridization appears to be very promising, innovative, and cost‐effective for biodiesel production. The present state of biodiesel production could be improved by the application of simple and cost‐effective technologies in the feedstock system. High free fatty acid (FFA) content is the major hurdle to the use of most oils, especially low‐grade/advanced oil feedstocks, in biodiesel production. This could be addressed through technological application of feedstock hybrids and biogenic waste‐derived heterogenous catalysts, and their biochemical modifications. Conventional technology for the large‐scale application of inorganically derived catalysts in biodiesel production with various characteristic differences is presented. Heterogenous catalysts derived from biogenic wastes and their modification could be used to overcome associated problems with the use of inorganic catalysts in biodiesel production. Biogenic waste‐derived heterogenous catalysts are renewable, available, eco‐friendly, and cost‐effective. Technological applications of heterogeneous catalysts derived from biogenic waste are outlined and reviewed, considering various materials and different modification techniques to identify appropriate options for scaling up development. This review also discusses fundamental considerations for the exploitation of feedstock hybrids to optimize biodiesel production and its sustainable development. © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd

Review: 183 refs.

A review of the feedstocks, catalysts, and intensification techniques for sustainable biodiesel production

A review on novel processes of biodiesel production from waste cooking oil

Changes in climate due to the enormous amount of carbon dioxide emissions have really encouraged the development of energy sources that are renewable, sustainable, and eco-friendly. The development of alternative energy sources can also be attributed to the rapid decrease in resources of fossil energy. Biodiesel has gained significant interest in recent years due to its fossil fuel–like properties and sustainable and eco-friendly characteristics. However, most biodiesels are expensive because of the high cost of feedstock largely based on edible vegetable oil sources. The use of animal fats waste as cost effective feedstock in biodiesel production has gained considerable attention in recent years. Although, most studies regarding the use of animal wastes as feedstock in biodiesel production are still in the early stages, the advantages of this type of feedstock have been highlighted in the literature. However, most studies have not focus on the recent advances in the use of animal fats waste. The studies on the use of novel approach have been reported in isolation. Therefore, this current study attempts to highlight recent developments of the most commonly used animal fats waste in the production of biodiesel. In addition, emphasis was given to the most appropriate production technique, catalyst, energy requirement, and optimum reaction conditions.

Biodiesel serves as a viable alternative to traditional diesel due to its non-toxicity, biodegradability, and lower environmental footprint. Among the diverse edible and inedible feedstocks, waste frying oil emerges as a promising and affordable feedstock for biodiesel production. Commonly waste frying oils include those derived from palm, corn, sunflower, soybean, rapeseed, and canola. The primary challenge related to biodiesel production technologies is the high production cost, which poses a significant barrier to its widespread adoption. Thus, refining the production techniques is essential to enhance yield, reduce capital expenditure, and curtail raw material expenses. An examination of the research focusing on feedstock availability, production, hurdles, operational expenditures, and future potential is pivotal for identifying the most economically and technically viable solutions. This paper critically reviews such research by exploring feedstock availability, production techniques, challenges, and costs intrinsic to biodiesel synthesis. It also underscores the economic feasibility of biodiesel production, shedding light on the pivotal factors that influence profitability, especially when leveraging waste frying oils. Through an in-depth understanding of these considerations, optimal production and feedstock choices for biodiesel production can be identified. Addressing cost and production bottlenecks could potentially enhance the economic viability of waste frying oil-based biodiesel, thus fostering both environmental sustainability and more extensive adoption of biodiesel as an environmental-friendly fuel in the future.

Biodiesel is an alternative diesel fuel made from renewable biological resources. During the process of biodiesel production, lipase-catalyzed transesterification is a crucial step. However, current techniques using methanol as acyl acceptor have lower enzymatic activity; this limits the application of such techniques in large-scale biodiesel production. Furthermore, the lipid feedstock of currently available techniques is limited. In this paper, the technique of lipase-catalyzed transesterification of five different oils for biodiesel production with methyl acetate as acyl acceptor was investigated, and the transesterification reaction conditions were optimized. The operation stability of lipase under the obtained optimal conditions was further examined. The results showed that under optimal transesterification conditions, both plant oils and animal fats led to high yields of methyl ester: cotton-seed oil, 98%; rapeseed oil, 95%; soybean oil, 91%; tea-seed oil, 92%; and lard, 95%. Crude and refined cottonseed oil or lard made no significant difference in yields of methyl ester. No loss of enzymatic activity was detected for lipase after being repeatedly used for 40 cycles (ca. 800 h), which indicates that the operational stability of lipase was fairly good under these conditions. Our results suggest that cotton-seed oil, rape-seed oil and lard might substitute soybean oil as suitable lipid feedstock for biodiesel production. Our results also show that our technique is fit for various lipid feedstocks both from plants and animals, and presents a very promising way for the large-scale biodiesel production.

Biodiesel production by ultrasound-assisted transesterification: State of the art and the perspectives

Review: 102 refs.

This chapter describes the advances on biodiesel production from microalgae adopting diverse methods of cultivation, harvesting and algal lipid extraction to biodiesel conversion techniques. It reviews integration of metabolic engineering approaches to enhance the biodiesel production by microalgae, scale-up strategies and challenges to achieve commercial feasibility of micro algal biodiesel production. Open cultivation systems are used in many algal industries for large scale production of microalgal biomass for food, feed, nutraceuticals and value-added products. Open cultivation systems are easier to construct and operate as compared to closed cultivation systems. Scale-up is a process to enlarge the production quantities with similar or higher productivity. Scale-up of microalgal biodiesel production is a crucial step due to the difficulty in assessing the process parameter affecting the scale-up. Biodiesel production from microalgal biomass has promising potential for commercialization. Many companies and researchers have developed techniques for microalgal biodiesel production.

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.

3 - Prospects of biodiesel feedstock as an effective ecofuel source and their challenges

Fast biodiesel production from beef tallow with radio frequency heating

Biodiesel production in micro-reactors: A review