Garbage to nanocellulose: Quantitative isolation and characterization of steam-treated carboxymethyl holocellulose nanofibrils from municipal solid waste

Authors: Patterson, Gabriel; McManus, James; MCSPEDON, DANE - Hughes Energy Llc; NAZNEEN, SAIRA - Hughes Energy Llc; Wood, Delilah - De; Williams, Tina; Hart-Cooper, William; Orts, William

Submitted to: ACS Sustainable Chemistry & Engineering
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/17/2023
Publication Date: 2/6/2023
Citation: Patterson, G.D., McManus, J.D., McSpedon, D., Nazneen, S., Wood, D.F., Williams, T.G., Hart-Cooper, W.M., Orts, W.J. 2023. Garbage to nanocellulose: Quantitative isolation and characterization of steam-treated carboxymethyl holocellulose nanofibrils from municipal solid waste. ACS Sustainable Chemistry & Engineering. 11(7). Article 2727-2736. https://doi.org/10.1021/acssuschemeng.2c05236.
DOI: https://doi.org/10.1021/acssuschemeng.2c05236

Interpretive Summary: The US generates about 1800 lbs of organic waste (kitchen waste, yard waste, paper, and cardboard) per person per year that end up in landfills where the decomposition of organic waste generates methane. Landfills are the third-largest source of methane emissions accounting for about 14.5% of methane emissions in 2020. Organic waste management must include a value-added component due to the unsustainability of the landfilling. An existing industrial steam process can transform organic waste in into a homogenous cellulosic fiber to produce a sustainable cellulosic material. We investigated the conversion of organic waste into cellulose nanofibrils by chemical treatment and shearing to produce a safe nanocellulose that may be used in the manufacture of high value products such as medical devices, electronics, and clothing.

Technical Abstract: Municipal solid waste (MSW) is a major source of greenhouse gas emissions unless its carbons are sequestered into highervalue products. This study focuses on isolating organic solids and cellulose-rich fibers from MSW via high-pressure steam treatment and converting the fibrous, prepulped materials from wastepaper, packaging materials, cardboard, etc., into value-added cellulose nanofibrils. Chemical-mechanical defibrillation of steam-treated municipal solid waste was optimized using heterogeneous and nonregioselective carboxymethyl etherification coupled with shearing by blender, thus transforming a heterogeneous mix of MSW into homogeneous carboxymethyl holocellulose nanofibrils without the use of conventional pretreatments of crude cellulosic feedstock. These carboxymethylated, hemicellulose-coated, cellulose nanofibrils were isolated quantitatively at >95% yield with widths 3-8 nm, thicknesses 1-3 nm, and lengths up to 1000 nm. We posit that this advancement of combining an inexhaustible, global supply of waste cellulose, large-scale steam autoclaving pretreatment, and an industrially relevant carboxymethylation processcould unlock the higher potential of sustainable cellulosic nanomaterials for a circular economy.