LIP-MB Laboratory (LR11ES24), INSAT - University of Carthage, Tunisia.
Department of Chemical Engineering, University of Murcia, Campus of Espinardo, E-30071 Murcia, Spain.
Bioresour Technol. 2015 Aug;190:281-8. doi: 10.1016/j.biortech.2015.04.097. Epub 2015 Apr 29.
A coupled process combining microalgae production with direct supercritical biodiesel conversion using a reduced number of operating steps is proposed in this work. Two newly isolated native microalgae strains, identified as Chlorella sp. and Nannochloris sp., were cultivated in both batch and continuous modes. Maximum productivities were achieved during continuous cultures with 318mg/lday and 256mg/lday for Chlorella sp. and Nannochloris sp., respectively. Microalgae were further characterized by determining their photosynthetic performance and nutrient removal efficiency. Biodiesel was produced by catalyst-free in situ supercritical methanol transesterification of wet unwashed algal biomass (75wt.% of moisture). Maximum biodiesel yields of 45.62wt.% and 21.79wt.% were reached for Chlorella sp. and Nannochloris sp., respectively. The analysis of polyunsaturated fatty acids of Chlorella sp. showed a decrease in their proportion when comparing conventional and supercritical transesterification processes (from 37.4% to 13.9%, respectively), thus improving the quality of the biodiesel.
本工作提出了一种将微藻生产与直接超临界生物柴油转化相结合的偶联过程，该过程操作步骤较少。两种新分离的本土微藻菌株，鉴定为绿球藻属和拟球藻属，在分批和连续培养模式下进行了培养。在连续培养中，绿球藻属和拟球藻属的最大生产率分别达到 318mg/d 和 256mg/d。通过测定微藻的光合作用性能和营养物质去除效率进一步对其进行了表征。通过无催化剂原位超临界甲醇酯交换法对未经洗涤的湿藻生物质（含水量为 75wt.%）进行生物柴油的生产。绿球藻属和拟球藻属的最大生物柴油产率分别达到 45.62wt.%和 21.79wt.%。对绿球藻属的多不饱和脂肪酸分析表明，与传统和超临界酯交换过程相比，其比例降低（分别从 37.4%降至 13.9%），从而提高了生物柴油的质量。
