4. Conclusions
To our knowledge, this is the first comprehensive study on the application of steam explosion technique for simultaneous lipid extraction and production of reducing sugars from microalgae. The experimental results demonstrate the efficacy and feasibility of the acid catalysed steam explosion pretreatment, followed with n-hexane lipid extraction. Remarkable sugar yields up to 96% were achieved under the pretreatment conditions of 1.7% sulphuric acid concentration and a temperature
of 150 °C during steam explosion. Besides, this study verified high efficiencies in the extraction of lipid of exploded microalgae using n-hexane against the low efficiencies obtained for the untreated microalgae. Steam explosion, as a single process step allows to access lipids to be extracted and hydrolyses most of the present carbohydrates, giving feed for both, biodiesel and bioethanol production.