ORIGINAL PAPER Sugarcane bagasse cellulose fibres and their hydrous niobium phosphate composites: synthesis and characterization by XPS, XRD and SEM P. H. F. Pereira • H. J. C. Voorwald • M. O. H. Cioffi • M. L. C. P. Da Silva • A. M. B. Rego • A. M. Ferraria • Maria Norberta De Pinho Received: 24 July 2013 / Accepted: 12 November 2013 / Published online: 24 November 2013 Ó Springer Science+Business Media Dordrecht 2013 Abstract Cellulose fibres obtained from sugarcane bagasse were submitted to a purification process, which consisted of an acid hydrolysis for elimination of the major part of lignin and hemicellulose. This was followed by a delignification process carried out in two steps to yield crude cellulose (CCell) fibres in the first one and with a subsequent bleaching in order to yield bleached cellulose fibres (BCell). Composites of crude and bleached cellulose fibres with hydrous niobium phosphate, cell/NbOPO 4 nH 2 O, were subse- quently synthesized. Scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray diffraction characterization of the obtained materials showed CCell/NbOPO 4 nH 2 O and BCell/NbOPO 4 nH 2 O are real composites. The nature of the cellulose (CCell or BCell) has an important role on the composites obtained, namely on the niobium salt composition at the composite surface. The synthesis of membranes of both cellulose and mixed matrix cellulose/NbO- PO 4 nH 2 O was only possible when the bleached cellulose was used. Keywords Bleaching  Cellulose  Morphology  XPS  XRD  SEM Introduction Large amounts of lignocellulosic materials are used worldwide for the production of consumable goods such as fuel products, paints, detergents, biodegradable polymers, textile fibres, composite materials, and other uses (Shaikh et al. 2009; Li et al. 2009; Karade 2010). In fact, this is associated with their great versatility, simple processing, low density, low cost and, with particularly, to their biodegradability (Arau ´jo et al. 2010; Corradini et al. 2009; One ´sippe et al. 2010; Xu et al. 2010). Brazil is one of the largest suppliers of alcohol and sugar in the world and has been using sugarcane as a major raw material for the production of both resources (Vieira et al. 2007; Dias et al. 2009). The processing of a ton of sugarcane generates 240 kg of bagasse with 50 % humidity (Dias et al. 2009), which P. H. F. Pereira (&)  H. J. C. Voorwald  M. O. H. Cioffi Fatigue and Aeronautical Materials Research Group, DMT/FEG/UNESP, Av. Ariberto Pereira da Cunha 333, Guaratingueta ´, SP Cep: 12516 410, Brazil e-mail: fernandes_eng@yahoo.com.br; fernandes_eng@yahoo.com M. L. C. P. Da Silva Chemistry Department, DEQUI/EEL/USP, Rod. Itajuba ´- Lorena, Km 74,5, Lorena, SP Cep: 12600 000, Brazil A. M. B. Rego  A. M. Ferraria Centro de Quı ´mica-Fı ´sica Molecular and Institute of Nanosciences and Nanotechnologies, Inst. Sup Te ´cnico, Univ. Te ´cnica de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal M. N. De Pinho Department of Chemical Engineering, Instituto Superior Tecnico, Univ. Te ´cnica de Lisboa, Av. Rovisco Pais, 1049-001 Lisbon, Portugal 123 Cellulose (2014) 21:641–652 DOI 10.1007/s10570-013-0113-2