The manuscript will undergo copy-editing, typesetting and revision of the resulting proof before being published in its final form. Due to the conical shape of the rotor and base, both of which have matching apex angles of 90°, the average shear stress increases as the fluid moves up the conical surface. Here, the mean shear is a function of the radial distance from the axis of rotation ( ) and the angular velocity of rotation.
The observations resulting from this study confirmed that the centrifugal motion of the rotor drives the liquid out and up the conical surface of the base in a spiral-like motion. Here the conical shape of the base represents a component of the gravitational force that opposes the outward motion of the fluid. At the end of the cultivation period, the fungal biomass was collected on a filter cloth and washed with tap water to remove residual growth medium.
To investigate the cell disruption effect of the T2FD, the fungal biomass before and after T2FD processing was analyzed using scanning electron microscopy (Inspect F50, Thermo Fisher Scientific, Australia). The fungal biomass slurry was premixed with methanol in a modified 60 mL syringe containing a magnetic stir bar, which was located above a magnetic stirrer to achieve homogeneity of the mixture. After collecting the methanol and catalyst-reacted cell lysate from the T2FD (~10 mL), the biodiesel was extracted with 10 mL of hexane.
Significance of the effect of catalyst concentration, biomass to methanol ratio, flow rate, rotation speed and water content was statistically analyzed for independent replicates (n = 3) using Statistica v13.6 at a significance set at α = 0.05.
Results and Discussion
Furthermore, differences in the molecular weights of the fatty acids have been attributed to an overestimation of saturated fatty acids (mol%) compared to the GC-derived wt% quantification (Sedman et al., 2010). The conversion efficiency of FA to FAME for both studies decreased at high concentrations of the basic catalyst, indicating that saponification occurred at excessive sodium hydroxide concentrations (Sitepu et al., 2018a). The effect of biomass to methanol ratio on T2FD-intensified fatty acid extraction (Fig. 2B) and FA to FAME conversion efficiency of M.
The ratio of biomass to methanol had no significant effect on C18:1 extraction, with efficiencies ranging from 84 ± 2 to 92 ± 3%, regardless of catalyst concentration. One of the most important factors affecting FA extraction and FA to FAME conversion efficiency is the reaction time (batch processing) or residence time (flow rate in continuous flow devices) (Britton et al., 2016). A factorial ANOVA determined a significant effect of catalyst concentration and flow rate on the T2FD extraction of C18:2, C18:1, and C16:0 from M.
Because the T2FD is a high-throughput device that can operate at much larger flow volumes, this result is consistent with the residence time being independent of flow rate because a minimum fluid volume is retained at this combination of flow rate and rotational speed. in the device. Fourteen parameters of the conversion efficiencies of T2FD, FA to FAME at 1% catalyst concentration were generally slightly but not significantly lower than those at 3% catalyst concentration (Fig. 3B). This result can be attributed to the increased evaporation loss of methanol in the T2FD, which aggravates the effect of the water content of the wet microalgal biomass (Sitepu et al. 2018b).
Rotational speed is one of the critical operating parameters of the T2FD, which can affect FA extraction and FA to FAME conversion efficiency. One of the main bottlenecks in biodiesel production is the dehydration of the biomass, which requires high energy inputs (Salam et al., 2016). Here, the Box-Behnken model predicted a decrease in FA to FAME conversion efficiency at high biomass to methanol ratios, increased water content and increased flow rates (Sitepu et al., 2018a).
This may indicate inhibition of DT by saponification of fatty acids by basic catalysts in the presence of water (Ma & Hanna, 1999) and/or reduced concentration of the catalyst at high water contents. For example, the conversion efficiencies from FA to FAME in this study ranged from < 2% in the absence of a catalyst. Thus, T2FD power consumption was based on a rotation speed of 4,000 rpm (38.4 W), the setting for most parameter assessments for the T2FD-intensified DT of dry M.
The energy consumption of the T2FD was lower than for the magnetic stir plate, which is typically used for conventional heating. Biodiesel production from wet biomass is definitely more energy wise, saving 46% by using a single step method instead of the traditional two step method.
Conclusion
In comparison, biodiesel production from Pichia guillermondii, which used sonication to disrupt cells prior to transesterification, using magnetic stirring. The authors acknowledge project funding through the Australian Research Council and the Government of South Australia. Biodiesel production from Mucor circinelloides using ethanol and heteropolyacid in one- and two-step transesterification.
Industrial waste as a promising renewable source for the production of microbial lipids and direct transesterification of the lipids into biodiesel. Integrated in situ transesterification for improved biodiesel production from oleaginous yeast: a value proposition for potential industrial implication. Conversion of paper mill sludge into neutral lipids by oleaginous yeast Cryptococcus vishniaccii for biodiesel production.
Efficacy of drying and cell destruction techniques on lipid recovery from microalgae for biodiesel production. Selection of microalgae species for biodiesel production based on fuel properties derived from fatty acid profiles. Biodiesel production by direct in situ transesterification of an oily tropical mangrove fungus grown on untreated agricultural residues and evaluation of its fuel properties.
Optimization of the in situ transesterification step for biodiesel production using Yarrowia lipolytica NCIM 3589 biomass grown on waste cooking oil. Ultrasonically assisted reactive extraction is a fast and simple method for the production of biodiesel from Jatropha curcas oilseeds. Evaluation of Specific Lipid Production and Nutrient Removal from Wastewater by Rhodosporidium toruloides and Biodiesel Production from Wet Biomass Using Microwave Irradiation.
Continuous flow reactive distillation process for biodiesel production using waste eggshells as heterogeneous catalysts. A sustainable integrated in situ transesterification of microalgae for biodiesel production and associated co-products-a review. Direct conversion of the oleaginous yeast Rhodosporidium diobovatum to biodiesel using the ionic liquid [C2mim][EtSO4].
Detergent-assisted ultrasound assisted in situ transesterification for biodiesel production from oleaginous yeast wet biomass. Comparison of energy (kWh kg-1 biomass) consumed for different biodiesel production methods based on this study and Chopra et al.
