Optimizing the yield and physico-chemical properties of pine cone cellulose nanocrystals by different hydrolysis time

• DOI: 10.1007/s10570-018-1760-0
• Publication Date: 2018-03-23T07:57:52Z
• Authors: Daniel García-García; Rafael Balart; Juan Lopez-Martinez; Monica Ek; Rosana Moriana
• Keywords: Sulfuric hydrolysis conditions; Cellulose nanocrystals; Materialkemi; Pappers-, massa- och fiberteknik; 02 engineering and technology; Paper, Pulp and Fiber Technology; Yield-recovery; Polymerteknologi; 16. Peace & justice; 01 natural sciences; Physico-chemical properties; 0104 chemical sciences; Pine cones; Yield-recovery.; CIENCIA DE LOS MATERIALES E INGENIERIA METALURGICA; Materials Chemistry; 0210 nano-technology; Polymer Technologies

[EN] Cellulose nanocrystals (CNCs) were isolated for the first time from pine cones (PC) by alkali and bleaching treatments and subsequent sulfuric acid hydrolysis (64 %) at 45 ºC. The influence of the hydrolytic reaction time (30, 45 and 90 min) on the yield, chemical composition and structure, and thermal stability of CNCs was evaluated. The removal of non-cellulosic constituents during the alkaline and bleaching treatment resulted in high pure cellulosic fibres. The isolation of CNCs from these cellulosic fibres at different reaction times was verified by the nano-dimensions of the individual crystals (< 3 and <335 nm of average diameter and length, respectively). The highest yield (15%) and the optimum CNCs properties in terms of aspect ratio, thermal stability and crystallinity were obtained for an extraction time of 45 min. PC appeared to be a new promising source of cellulose fibres and CNCs with potential to be applied as reinforcement in composites and for food-packaging.<br/>This work was supported by the Ministry of Economy and Competitiveness (MINECO) [MAT2014-59242-C2-1-R]. D. García-García wants to thanks the Spanish Ministry of Education, Culture and Sports for their financial support through an FPU Grant [FPU13/06011].<br/>