Multistage treatment of almonds waste biomass: Characterization and assessment of the potential applications of raw material and products

• Published in: Waste management (Elmsford) 2018-10, Vol.80, p.40-50
• Main Authors: de Hoyos-Martínez, Pedro L., Erdocia, Xabier, Charrier-El Bouhtoury, Fatima, Prado, Raquel, Labidi, Jalel
• Format: Article
• Language: English
• Subjects: Almond shells; Analytical chemistry; Biomass; Cellulose; Chemical Sciences; Lignin; Material chemistry; or physical chemistry; Polymers; Prunus dulcis; Renewable products; Theoretical and; Waste biomass
• ISSN: 0956-053X; 1879-2456
• DOI: 10.1016/j.wasman.2018.08.051

[Display omitted] •The valorization of waste biomass from almond agriculture activities was achieved.•A novel multistep organosolv process of almond shells was carried out.•An extensive mass balance was done, providing a full understanding of the process.•Pulps with high cellulose content remained after each extraction cycle.•Highly pure (≈90%) and reactive lignins were obtained after each stage. Almond shells are waste biomass generated in agro-industrial activities, which represent a resource that can be further valorized upon treatment. The purpose of this work was to assess new value-added products obtained through a novel multi-stage delignification process of almond shells. A comprehensive chemical characterization of the raw materials and products involved in each stage of the process was carried out. Moreover, an extensive mass balance was developed, providing a full understanding of the extraction process. The pulps produced did not display a significant cellulose loss and hence they could be exploited as cellulose-rich materials. On the other hand, the obtained lignins presented high purity values (≈90%) and a high reactivity, and their structures became more condensed and homogeneous after each extraction cycle. These features would allow their utilization as feedstock of renewable materials such bio-sourced phenolic resins.