Extraction and modification of cellulose nanofibers derived from biomass for environmental application

Abstract

Cellulose is a natural biopolymer that is abundantly available in plant cell walls and is secreted in its pure forms by many bacteria. Due to their unique features cellulose materials are considered as efficient replacements for conventional polymers. Cellulose nanofibers (CNF) have attracted wide interest due to their nano size, ease of preparation, low cost, tuneable surface properties and enhanced mechanical properties. However, the efficiency of CNF depends on the extraction method employed from its source and their features vary from source to source. Hence, there is a need to understand the specificity of CNF extraction from its source in order to obtain highly efficient CNF with maximum potential. CNF has been extracted from plant sources using physical, chemical and enzymatic methods. Although plant derived CNF possess excellent features, the involvement of chemicals and complexity in extraction process limits their usage. Bacterial CNF overcome this limitation through its extracellular secretion which makes extraction easy. CNF is also extracted from various marine filamentous algae. The percentage of CNF obtained from algal sources is less compared to plants and bacterial sources. CNF finds wide variety of applications such as drug carriers, tissue regenerating scaffolds, water purifying Ms. Mridula Prakash Menon is presently working as a PhD Research Scholar in the Nanobiotechnology laboratory at PSG Institute of Advanced Studies, Coimbatore, Tamil Nadu, India. She has completed her Masters in Biotechnology and M.Phil. in Nanoscience and Technology at PSG Institute of Advanced Studies. Her research interests include synthesis of nanomaterials for biomedical and environmental applications, microbial biotechnology, water puri-cation, and bioremediation and drug delivery. 151 Commercially obtained Electrospinning Size; 4.6 AE 1.8 mm and 8.1 AE 2.2 mm, high uid permeability (8.9 Â 10 À12 m 2 ) 152 42754 | RSC Adv., 2017, 7, 42750-42773 This journal isFig. 1 SEM images of various types of CNF synthesized from cotton (a) natural electrospun CNF 56 (b) aligned CNF (scale bar 1 mm) 54 (c): CdS functionalized CNF 33 (d): CeO 2 functionalized CNF 56 (e): CNF prepared by acid hydrolysis 52 (adopted with permission).This journal is

Bio‐Based Nanofibers Involved in Wastewater Treatment

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New highly hydrated cellulose microfibrils with a tendril helical morphology extracted from agro-waste material: application to removal of dyes from waste water

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Rheological and mechanical properties of cellulose/LDPE composites using sustainable and fully renewable compatibilisers

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