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• 72% − 80% of fibre was recovered from disposable coffee cups. • 2% and 3% consistency shredded cups required > 100 kWh/tonne to repulp with 3 refiner passes. • Pulp quality did not significantly diminish after repulping using a single-disk refiner. Over 64 billion paper-plastic laminate (PPL) coffee cups are consumed between the United States and Canada annually, the majority accumulating in landfills due to a hydrophobic plastic inner-lining. Recycling can mitigate environmental damage and provide economic value from repurposed products. We found that standard repulping methods were insufficient to separate fiber from plastic due to the low intensity of treatment. To increase process intensity, we mechanically refined shredded PPL coffee cups and Kraft eucalyptus sheets (control) at 2%, 3%, and 4% consistencies with three passes to determine the energy required to separate fibers from plastic and the effects on fiber quality. 2% and 3% consistency PPL cups measured under 40 kWh/tonne of input material for one refiner pass and ∼ 80 kWh/tonne for 4% consistency PPL cups. Recovered fiber fraction totaled 87.7%, 85.3%, and 80.5% of input mass of Kraft eucalyptus and 72.3%, 72.6%, and 79.6% of input mass of PPL cups at 2%, 3%, and 4% consistency, respectively. Fines content of PPL cups jumped from 8% pre-refining to ∼ 30% post-refining while Kraft eucalyptus fibers were unaffected, suggesting that breaking the plastic-fiber bonds results in fines generation. Mean fiber length of PPL cups slightly decreased with consistency and tensile strength improved. Freeness decreased with consistency only in PPL cup samples. These results demonstrate a low energy requirement to effectively separate fiber and plastics in PPL cups as well as minimal impact on fiber quality using existing refining technology, and provides an estimate of the financial costs of local recycling efforts. [ABSTRACT FROM AUTHOR]

Innovative sustainable products can contribute to slowing climate change while simultaneously driving economic growth. In this study, we describe a 'green' technology to produce a porous, lightweight cellulose-mycelium foam (CMF) in which fungal mycelium is grown for applications such as filtration, packaging, and bioremediation. Fluorescent microscopy revealed incomplete fiber degradation after 25 days of fungal growth, and that mycelium grew along fibers and within the pores of the CMF. The physio-mechanical properties of the CMF were investigated via compressibility, thermogravimetric analysis, and dry and wet tensile strength for samples grown for 0, 15, and 25 days. Thermal stability increased with mycelium growth, showing extrapolated onset temperatures of 227.5 °C, 312.7 °C, and 325.5 °C for 0, 15, and 25 days, respectively. Tensile strength and compressibility were notably improved with mycelial growth. CMF permeability, filtration efficiency, and pressure drop were tested, and we observed a decrease in permeability with mycelium growth in foam fiber, and hydraulic filtration efficiency measured 99.9% for particles sized 20 µm or larger. Living CMF neutralized potassium hydroxide leaks from alkaline batteries, decreasing pH from 12 to 6 over a 60-day period. These results demonstrate a wide range of material improvements, showing promise for practical filtration, thermal insulation, and bioremediation applications while being both sustainable and biodegradable. [ABSTRACT FROM AUTHOR]