Integrated approach for enhanced bio-oil recovery from disposed face masks through co-hydrothermal liquefaction with Spirulina platensis grown in wastewater

Abstract

Graphical abstract Currently, the enormous generation of contaminated disposed face masks raises many environmental concerns. The present study provides a novel route for efficient crude bio-oil production from disposed masks through co-hydrothermal liquefaction (Co-HTL) with Spirulina platensis grown in wastewater. Ultimate and proximate analysis confirmed that S. platensis contains relatively high nitrogen content (9.13%dw), which decreased by increasing the mask blend ratio. However, carbon and hydrogen contents were higher in masks (83.84 and 13.77%dw, respectively). In addition, masks showed 29.6% higher volatiles than S. platensis , which resulted in 94.2% lower ash content. Thermal decomposition of masks started at a higher temperature (≈330 °C) comparing to S. platensis (≈208 °C). The highest bio-oil yield was recorded by HTL of S. platensis and Co-HTL with 25% ( w/w ) masks at 300 °C, which showed insignificant differences with each other. GC/MS analysis of the bio-oil produced from HTL of algal biomass showed a high proportion of nitrogen- and oxygen-containing compounds (3.6% and 11.9%, respectively), with relatively low hydrocarbons (17.4%). Mask blend ratio at 25% reduced the nitrogen-containing compounds by 55.6% and enhanced the hydrocarbons by 43.7%. Moreover, blending of masks with S. platensis enhanced the compounds within the diesel range in favor of gasoline and heavy oil. Overall, the present study provides an innovative route for enhanced bio-oil production through mask recycling coupled with wastewater treatment. Supplementary Information The online version contains supplementary material available at 10.1007/s13399-021-01891-2.

Disposal and resource utilization of waste masks: a review

“…The quality and quantity of bio-oil obtained by co-pyrolysis of waste biomass were better than those obtained by pyrolysis of single raw material (Abnisa and Daud 2014 ; Gouws et al 2021 ; Uzoejinwa et al 2018 ). Li et al ( 2021 ) used Spirulina platensis for co-hydrothermal liquefaction with waste masks at a relatively low temperature compared to simple pyrolysis. The yield of oil was up to 23.0% at 300 °C, which was much higher than the yield (7.0%) of hydrothermal liquefaction of individual waste masks.…”

“…The yield of oil was up to 23.0% at 300 °C, which was much higher than the yield (7.0%) of hydrothermal liquefaction of individual waste masks. The yield of hydrocarbons within the diesel range increased in favor of heavy oil and gasoline by blending masks with Spirulina platensis (Li et al 2021 ). Luo et al ( 2021b ) co-pyrolyzed mask with the heavy fraction of bio-oil to obtain a series of biochar, bio-oil, and graphene films.…”

Thermochemical recycling of waste disposable facemasks in a non-electrically powered system

“…In the year 2019, the deadly coronavirus disease (COVID- 19) ravaged the entire planet with a fatality rate of more than five million deaths [1,2]. To assist in battling the pandemic, the use of plastic-based personal protective equipment (PPEs) such as hand sanitizer bottles, medical suits, gloves, and facemasks was encouraged, as well as social distancing [3].…”

Optimal use of glycerol co-solvent to enhance product yield and its quality from hydrothermal liquefaction of refuse-derived fuel

“…The enormous generation and disposal of used face masks in the last few years have also raised serious environmental concerns. Co-liquefaction of biomass with face masks at 300 °C is reported to increase the diesel fraction (C 16 –C 21 ) and decrease the heavy fractions (C 25 –C 42 ) in the bio-crude [ 15 ]. Wastes such as plastics and face masks are inherently present in RDF and contribute to the high hydrogen content in the feedstock.…”