Trends in Biodiesel Production from Animal Fat Waste

Abstract

The agro-food industry generates large amounts of waste that contribute to environmental contamination. Animal fat waste constitutes some of the most relevant waste and the treatment of such waste is quite costly because environmental regulations are quite strict. Part of such costs might be reduced through the generation of bioenergy. Biodiesel constitutes a valid renewable source of energy because it is biodegradable, non-toxic and has a good combustion emission profile and can be blended up to 20% with fossil diesel for its use in many countries. Furthermore, up to 70% of the total cost of biodiesel majorly depends on the cost of the raw materials used, which can be reduced using animal fat waste because they are cheaper than vegetable oil waste. In fact, 6% of total feedstock corresponded to animal fat in 2019. Transesterification with alkaline catalysis is still preferred at industrial plants producing biodiesel. Recent developments in heterogeneous catalysts that can be easily recovered, regenerated and reused, as well as immobilized lipases with increased stability and resistance to alcohol denaturation, are promising for future industrial use. This manuscript reviews the available processes and recent advances for biodiesel generation from animal fat waste.

Low-quality animal by-product streams for the production of PHA-biopolymers: fats, fat/protein-emulsions and materials with high ash content as low-cost feedstocks

“…Also, the low-quality animal by-product streams studied have the advantage that they are not or not well suitable for other industries as e.g. the biodiesel industry, due to their very high content of free fatty acids and/or proteins, ash and low total fat content (Toldrá-Reig et al 2020 ).…”

Animal Fat as a Substrate for Production of n-6 Fatty Acids by Fungal Solid-State Fermentation

“…The increasing worldwide demand for meat products is accompanied by the emergence of new challenges. Meat production is linked to generating large amounts of animal fat by-products (millions of tons) and the majority of challenges are associated with inevitable post-production storage or fully ecological liquidation of accumulated by-products [ 1 , 2 ]. Animal fat by-products or waste fractions may cause devastating physical effects on the ecosystem, produce rancid odors, or form toxic products that can linger in the environment for many years.…”

“…At present, several studies describe the possibility of biodiesel production from animal fat by-products as input material with relatively high efficiency [ 2 , 3 , 4 ]. However, this fat-based by-product may not be just a suitable matrix for its direct transesterification to biodiesel.…”

Effect of zeolitic nano-catalyst on biodiesel yield and biochar formation during the pyrolysis of tallow

“…Other sources and uses of animal wastes that could be considered for biodiesel production are presented in Figure 1. Fats are found in living organisms, consisting essentially of fatty acid esters and glycerin mixtures, known as triacylglycerols or triglycerides [13]. These triacylglycerols have high viscosities, therefore they cannot be used directly as fuels in common diesel engines but will need to be refined to conform with diesel properties.…”