The use of sunflower biomass as a raw material for bioethanol production requires its pre-treatment to destroy the lignocellulosic structure, which makes the access of enzymes to the cellulose chains easier or directs the use of their lignocellulosic fractions. The data on the theoretical yield of bioethanol from different types of biomass is provided in the table below.
The pre-treatment by steam and simultaneous saccharification and fermentation makes it possible to obtain 1 l of ethanol from 3.8 kg of pretreated sunflower stalks. In terms of the equivalent amount of raw material, it can be produced 101.4 liters of bioethanol from 1 ton of sunflower stalks. Prehydrolysis at the temperature of 180-230°C with simultaneous saccharification and fermentation makes it possible to obtain 12 g of bioethanol/100 g of sunflower stalks (150 l/t), which is equivalent to 72.2% of the theoretical yield. A typical scheme of bioethanol production from lignocellulosic raw material is shown in the figure below.
In a study of growing four varieties of sunflower in the semi-arid region of north-eastern Brazil with further processing into liquid biofuels46 (seeds for biodiesel, and stalks and heads for bioethanol), from one hectare was received 2537 kg d.m. of by-products and 1635 kg d.m. of seeds, respectively, 663 kg/ha of oil and 1115 kg/ha of sugars (871 kg/ha of cellulose and 244 kg/ha of hemicellulose). It was possible to obtain 293 l of bioethanol/ha from this amount of sunflower by-products.
 Osiris Ashton Vital Brazil et al. Integral use of lignocellulosic residues from different sunflower accessions: Analysis of the production potential for biofuels. Journal of Cleaner Production 221 (2019) 430-438.
 Ruiz, E., Cara, C., Ballesteros, M., Manzanares, P., Ballesteros, I., & Castro, E. (2006). Ethanol Production From Pretreated Olive Tree Wood and Sunflower Stalks by an SSF Process. Applied Biochemistry and Biotechnology, 130(1-3), 631–643.
 Evelin Raquel Ruiz et al. Strategies for bioethanol production from sunflower stalks Afinidad –Barcelona – 68 (556): 417-423. – November, 2011.