Advances in microalgal lipid extraction for biofuel production: a review

Abstract

Algal biomass is an attractive feedstock for sustainable biofuel production because of its high growth rate and the fact that it does not compete with food crops. This review examines progress made in the processing and extraction of microalgal lipids as feedstocks for algae‐derived biofuels. The discussion focuses on lipid extraction processes but also mentions drying, cell disruption, and transesterification processes because of their potential effect on the extraction process, and because of the possibility of performing them simultaneously with extraction. Some of the common themes discussed include the benefits of utilizing wet microalgal biomass, combining process steps (process intensification), and the importance of considering the entire life cycle when assessing the ‘greenness’ of a technology. Lipid extraction technologies will need to be improved for microalgal biofuels to compete effectively with fossil fuels, particularly through the development of energy‐efficient extraction methods and the adaptation of these methods for large‐scale production. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd

Mexican Microalgae Biodiversity and State-Of-The-Art Extraction Strategies to Meet Sustainable Circular Economy Challenges: High-Value Compounds and Their Applied Perspectives

“…Still, the feasibility of scaling up microwave extraction techniques into an industrial level is still under research; because its high energy operating costs might present a major drawback of this process. For instance, the use of enzymes is expensive, especially for large scale applications when competing against other methods [59]. Moreover, this method cannot complete the separation process by itself and usually requires a subsequent centrifugation or filtration process [60].…”

“…Further, while temperature extraction conditions are amiable, pressure operating parameters still need to be decreased for general industrial implementation. While previous studies have been able to optimize industrial relevant conditions for supercritical extraction of lipids from Scenedesmus obliquus, Chlorella protothecoides and Nannochloropsis salina [65], optimal pressure conditions can range between 30 MPa and 50 MPa in some cases [59], thus representing an area of opportunity for further optimization of the standardized application. Polyunsaturated fatty acids like ω-3 and ω-6 types have been successfully extracted by SFE using CO 2 and n-butane.…”

“…The production of biodiesel is currently done by processing oily seeds from palm, castor bean, sunflower, corn, and cotton, among others [163,164,165]. As discussed before, microalgae are a huge producer of fatty acids that can be converted into biodiesel [59]. For instance, around 50% of Chlorella, Nannochloropsis, Dunaliella, Scenedesmus, and Scenedesmus composition are lipids.…”

Towards green extraction methods from microalgae learning from the classics

“…They are typically composed of a large number of inorganic or organic cations and are characterized by synthetic flexibility and thermal stability. Moreover, they are non-volatile and non-flammable (Vekariya 2017;Harris et al 2018), being a good alternative to conventional solvents. They are generally employed for lipid extraction; however, to date, only limited papers are available in literature (Motlagh et al 2019).…”

“…(Domínguez de María 2017;Harris et al 2018;Singh and Savoy 2020). In recent years, a second generation of ILs has been developed: switchable solvents (SSs).…”