Extraction and characterisation of cellulose nanocrystals from pineapple peel

• Autor(a) principal: Madureira, Ana Raquel
• Data de Publicação: 2018
• Outros Autores: Atatoprak, Tugba, Çabuk, Duygu, Sousa, Flávia, Pullar, Robert C., Pintado, Manuela
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.14/25960
• topic: Cellulose; CNC; Pineapple peels

The potential of pineapple peel as a source of cellulose nanocrystals was evaluated. Peels skin from fresh-cut fruit was used as raw material. These residues were puri ed to remove pigments, lipids and hemicellulose, and a bleaching process for deligni cation was carried out for 4-6 h. All resulting products were characterised for their lignin, hemicellulose, cellulose and ash contents using standard techniques. Dry matter at the end was low (ca. 50%) compared with the raw material (ca. 90%). The process applied resulted in ca. 20% (m/m) of puri ed cellulose (ca. 80% purity), with ineligible levels of lignin and hemicellulose present, especially when using 6h of bleaching. The puri ed cellulose was subject to acid hydrolysis for nanocrystal extraction with two testing times, 30 and 60 minutes. These cellulose nanocrystals had small sizes (< 1000 nm), with high variability and negative zeta potential values. The time of extraction did not a ect the nanocrystals' chemical and physical properties. The use of 6 h of bleaching treatment during puri cation was shown to be more e ective than 4 h. Pineapple peel was demonstrated to be a good source of cellulose for the production of cellulose nanocrystals.