An Overview of Criteria of Lignocellulosic Waste and Residues for Packaging Production Leading to Circular Bioeconomy

Extensive use of petrochemical plastic packaging, coupled with the lack of systematic collection and disposal, leads to a major contamination in soils and aquatic environments. In response, widespread research is taking place to replace petrochemical plastics with biodegradable polymers i.e. substances capable of being decomposed avoiding environmental pollution. Lignocellulose (LC), the most abundant biomass composites from forest and agriculture, can produce cellulose nanofibrils (CNF), a biodegradable packaging material with significant mechanical, barrier and colloidal properties, low density and renewability. However, the cost of production and the negative environmental impact of agricultural expansion are two major obstacles for commercial upscaling of CNF production. Compared to primary resources, CNF extracted from lignocellulosic wastes and residues (LCW&R) e.g. primary forestry and agricultural residues, and municipal and industrial LC- based wastes, not only lowers the production cost but also removes the need for cropland expansion. Moreover, the use of LCW&R in CNF production, indicating material recovery and recycling in the Waste hierarchy (i.e. the ranking of waste management options), provides a more profitable, environment friendly biowaste treatment compared to incineration and landfilling. Various feedstock criteria influences the properties, performance, processing efficiency and production cost of CNFs. Understanding of how the feedstocks perform across these criteria is required for the optimal feedstock selection in commercial CNF production. However, a consolidated overview of criteria defining the suitability of LCW&R for optimal CNF production is absent in the literature. Therefore, this study performs an iterative literature review and presents an overview of the LCW&R characteristics to consider for the successful commercial production of CNF as a packaging material. The 14 criteria of LCW&Rs identified in this study are: availability; elemental composition; cellulose content; hemicellulose content; lignin content; ash content; cell wall thickness; price, seasonal variability; durability; bulk density; environmental impact; land impact; and biodiversity impact. The results of the study can be used to support decisions on managing lignocellulosic waste and producing bioplastic packaging that can enable circular bioeconomy.