scholarly journals Physical Methods of Microalgal Biomass Pretreatment

2014 ◽  
Vol 28 (3) ◽  
pp. 341-348 ◽  
Author(s):  
Agata Piasecka ◽  
Izabela Krzemińska ◽  
Jerzy Tys

Abstract The prospect of depletion of natural energy resources on the Earth forces researchers to seek and explore new and alternative energy sources. Biomass is a composite resource that can be used in many ways leading to diversity of products. Therefore, microalgal biomass offers great potential. The main aim of this study is to find the best physical method of microalgal biomass pretreatment that guarantees efficient lipid extraction. These studies identifies biochemical composition of microalgal biomass as source for biodisel production. The influence of drying at different temperatures and lyophilization was investigated. In addition, wet and untreated biomass was examined. Cell disruption (sonication and microwave) techniques were used to improve lipid extraction from wet biomass. Additionally, two different extraction methods were carried out to select the best method of crude oil extraction. The results of this study show that wet biomass after sonication is the most suitable for extraction. The fatty acid composition of microalgal biomass includes linoleic acid (C18:2), palmitic acid (C16:0), oleic acid (C18:1), linolenic acid (C18:3), and stearic acid (C18:0), which play a key role in biodiesel production.

2013 ◽  
Vol 133 ◽  
pp. 378-388 ◽  
Author(s):  
Sergio D. Ríos ◽  
Joandiet Castañeda ◽  
Carles Torras ◽  
Xavier Farriol ◽  
Joan Salvadó

Catalysts ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 231 ◽  
Author(s):  
Anam Fatima ◽  
Muhammad Waseem Mumtaz ◽  
Hamid Mukhtar ◽  
Sadia Akram ◽  
Tooba Touqeer ◽  
...  

Biodiesel has emerged as one of the most attractive alternative energy sources to meet the growing needs of energy. Many approaches have been adopted for biodiesel synthesis. In the present work, biodiesel was produced from non-edible Eruca sativa oil using nano-biocatalyst-catalysed transesterification. Nano-biocatalyst (CeO2@PDA@A. terreus Lipase) was developed via the immobilization of lipase on polydopamine coated ceria nanorods, and CeO2 nanorods were developed via a hydrothermal process. The mean diameter of nanorods were measured to be 50–60 nm, while their mean length was 150–200 nm. Lipase activity before and after immobilization was measured to be 18.32 and 16.90 U/mg/min, respectively. The immobilized lipase depicted high stability at high temperature and pH. CeO2@PDA@A. terreus Lipase-catalysed transesterification resulted in 89.3% yield of the product. Process optimization through response surface methodology was also executed, and it was depicted that the optimum/maximum E. sativa oil-based biodiesel yield was procured at conditions of 10% CeO2@PDA@A. terreus Lipase, 6:1 methanol/oil ratio, 0.6% water content, 35 °C reaction temperature, and 30 h reaction time. The fuel compatibility of synthesized biodiesel was confirmed via the estimation of fuel properties that were in agreement with the ASTM D standard. The nanorods and dopamine-modified nanorods were characterized by FTIR spectroscopy, SEM, and energy dispersive X-ray (EDX), while conversion of E. sativa oil to biodiesel was confirmed by GC/MS and FTIR spectroscopy. Conclusively, it was revealed that CeO2@PDA@A. terreus Lipase has potential to be employed as an emphatic nano-biocatalyst.


2015 ◽  
Vol 14 (1) ◽  
pp. 22
Author(s):  
L. Schroeder ◽  
M. D. Scherer ◽  
W. Balmant ◽  
A. B. Mariano ◽  
J. V. C. Vargas

he production of biodiesel from lipids extracted from microalgae biomass is a promising approach to biofuels. However, this approach is still not commercialized because of the high costs of processes associated with, for example, time consumption and / or biomass drying with intense energy usage. However, it was not possible to show extraction methods among the lipids existing in the literature, which could be applied specifically to the extraction of lipids from the microalgae Scenedesmus sp. from the large-scale wet biomass, which is the current challenge faced by the Center for Research and Development of Sustainable Energy Auto (NPDEAS). Therefore, in this study, the possibility of avoiding the drying process, and extracting lipids directly from humid biomass, using the saponification method, was tested and compared with conventional Bligh and Dyer extraction (B & D). This study introduced the cultivation of microalgae Scenedesmus sp. compact tubular photobioreactors 12 m3 in area 10 m2 (8 x 5 x 2 m). The classical method of lipid extraction from microalgae - B & D - brings many pigments and polar lipids that exist in the biomass and the conversion rate was only 65-66%, whereas the recovery of fatty material in the wet biomass by the saponification method showed high conversion rate (90-95%). Therefore, the saponification process showed a high recovery of fatty acids that can be easily converted into biodiesel by esterification, and it was shown that the stage of drying the biomass can be removed without losing the fatty acids. In relation to the energy usage in the process, it was shown that drying the biomass for extraction of fatty acids uses more energy than that produced in the final product, biodiesel, showing that the removal of fatty acids of the wet biomass is of strategic importance to the viability of microalgae biodiesel.


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Tatiana Rodrigues da Silva Baumgartner ◽  
Jorge Augusto Mendes Burak ◽  
Dirceu Baumgartner ◽  
Gisella Maria Zanin ◽  
Pedro Augusto Arroyo

The increasing energy demand and reduction in the availability of nonrenewable energy sources, allied with an increase in public environmental awareness, have stimulated a search for alternative energy sources. The present study was aimed at producing biomass from the microalgaSpirulina platensisand at assessingin situsynthesis of alkyl esters via acid transesterification/esterification of biomass to produce biodiesel. Two alcohols (ethanol and methanol) and two cosolvents (hexane and chloroform) were tested, at different temperatures (30, 45, 60, 75, and 90°C) and reaction times (10, 20, 30, 60, and 120 min). The factorial analysis of variance detected an interaction between the factors (): temperature, reaction time, alcohol, and cosolvent. The best yields were obtained with the combination ethanol and chloroform at 60°C, after 30 min of reaction, and with hexane at 45°C, after 10 min of reaction.In situtransesterification/esterification of alga biomass to form esters for biodiesel production adds unconventional dynamics to the use of this feedstock.


2019 ◽  
Vol 11 (23) ◽  
pp. 6572 ◽  
Author(s):  
Eleonora Bottani ◽  
Letizia Tebaldi ◽  
Andrea Volpi

As never before, there is nowadays the will to consider alternative energy sources from renewable and waste materials so as to preserve planet and society. One of the possible elements suitable for this purpose is every day in our houses: Coffee. Or rather, spent coffee grounds. Indeed, many studies in recent years have addressed its potential exploitation, especially for biodiesel production; recent works also pointed out its possible thermal valorization for industrial processes. In light of this, this paper proposes a new sustainable use of spent coffee grounds, converted into combustible pellets; this source can then be used not only for industrial heaters, but also for public or private buildings. To this end, a feasibility study of a pellet production plant fed by waste collected by vending companies operating in the North of Italy is developed, including the logistic model supported by an Information and Communication Technology (ICT) system to help gather spent coffee grounds from the different companies and collect them into the pellet production facility.


2021 ◽  
Vol 13 (12) ◽  
pp. 6606
Author(s):  
Laura Vélez-Landa ◽  
Héctor Ricardo Hernández-De León ◽  
Yolanda Del Carmen Pérez-Luna ◽  
Sabino Velázquez-Trujillo ◽  
Joel Moreira-Acosta ◽  
...  

Microalgal biomass has the capacity to accumulate relatively large quantities of triacylglycerides (TAG) for the conversion of methyl esters of fatty acids (FAME) which has made microalgae a desirable alternative for the production of biofuels. In the present work Verrucodesmus verrucosus was evaluated under autotrophic growth conditions as a suitable source of oil for biodiesel production. For this purpose BG11 media were evaluated in three different light:dark photoperiods (L:D; 16:08; 12:12; 24:0) and light intensities (1000, 2000 and 3000 Lux) in a photobioreactor with a capacity of three liters; the evaluation of the microalgal biomass was carried out through the cell count with the use of the Neubauer chamber followed by the evaluation of the kinetic growth parameters. So, the lipid accumulation was determined through the lipid extraction with a Soxhlet system. Finally, the fatty acid profile of the total pooled lipids was determined using gas chromatography-mass spectroscopy (GC-MS). The results demonstrate that the best conditions are a photoperiod of 12 light hours and 12 dark hours with BG11 medium in a 3 L tubular photobioreactor with 0.3% CO2, 25 °C and 2000 Lux, allowing a lipid accumulation of 50.42%. Palmitic acid is identified as the most abundant fatty acid at 44.90%.


Sign in / Sign up

Export Citation Format

Share Document