Comparative Study of Lignocellulosic Nanomaterials Production from Different Heterogeneous Waste Feedstocks

Nanocellulose products may be produced from various heterogeneous waste feedstocks such as agricultural residues, invasive plant species, and other low-cost lignocellulosic biomass, providing economic and sustainability advantages related to the conventional bleached wood pulp feedstock. However, for this to become a reality on a large scale, robust conversion processes that accommodates such heterogeneous feedstocks must be developed. In this study, four different heterogeneous waste feedstocks were utilized (wheat straw, corn stover, reed canary grass, and industrial hemp) to assess the robustness of a novel conversion process previously developed by our group to make lignocellulosic nanomaterials. In our process we utilize inexpensive lignocellulosic feedstock and mild peracetic acid (PAA) pretreatment to produce lignocellulosic nanomaterials (nano and microfibrils) with potential bioplastics applications. PAA was chosen due to its biodegradability, non-toxicity, and high reaction selectivity.<br/><br/>Lignocellulosic nanofibrils (LCNF) and microfibrils (LCMF) were successfully produced from all biomass feedstocks tested, but the original biomass's chemical and physical characteristics influenced the final nanomaterials’ properties. The chemical composition and nature of the initial feedstock showed a direct effect on the total mass yields during the process as well as on the surface charge of the final nanomaterials. In addition, the physical characteristics of the feedstock affected the degree of delignification during the reactions, producing materials with different residual lignin contents. This work has demonstrated the successful production of nanomaterials from various low-cost waste feedstocks, advocating for the large-scale production of nanocellulose products in the United States.