Current insights into lignocellulose related waste valorization

Abstract

Lignocellulose waste management involves economic, environmental and social costs that will increase in the future because, given the greenhouse gas (GHG) emissions generated by organic waste disposal, landfilling will be reduced and even forbidden in some places as a climate change mitigation measure. The Waste Framework Directive (WFD) aims to turn the EU into a recycling society by transforming linear economy processes into circular economy ones. Several methods have been studied to replace authorized landfill and/or incineration with environment friendly processes based on the fact that lignocellulose related waste can be transformed into high-value-added products, and is a source of energy and chemicals. These include recycling as a by-product by incorporating it into materials as a biocomposite, cement, asphalt, adsorbent or absorbent. It can also be recycled for land applications in agriculture and silviculture by composting, or used for energetic valorization by combustion, anaerobic digestion, pyrolysis, bioethanol, biomethane, hydrogen production or direct liquefaction. Hydrolysis to obtain glucose and other high-value-added products, and synthesis of biopolymers, biocomposites, nanofibers and nanoparticles from cellulose based waste, are other approaches that can also be considered. In this short review we present and analyze all these possibilities, taking into account the initial treatments that are required to be able to take advantage of cellulose related waste.

Keywords

• Lignocellulose waste
• Recycling
• Energetic valorization
• Biomaterial