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Wet air oxidation (WAO) of the PPE mixture was performed at temperatures ranging from 300 °C to 350 °C, with initial air pressures of 30 bar and 60 bar, respectively. Total suspended solids (TSS) were reduced by up to 99%, while total chemical oxygen demand (tCOD) and soluble chemical oxygen demand (sCOD) were significantly reduced to 360 mg/L and 110 mg/L, respectively. The main products were volatile fatty acids such as acetic and propionic acids and ammonia nitrogen (NH 3 -N) with concentrations of up to 1117 mg/L, 975 mg/L, and 18 mg/L, respectively. Nitrogen and oxygen were the most abundant gaseous products, reaching 72% (w/w) and 14% (w/w), respectively. Semi-batch WAO treatments were carried out at 300 °C and 350 °C to achieve comparable waste reduction. The results suggest that non-catalytic WAO is a viable PPE waste management solution. [Display omitted] • Up to 98.8% of the mixture of selected single-use PPE items was deconstructed. • Up to 18 mg/L ammonia was detected in the resultant reaction mixture. • Volatile fatty acids, mainly acetic acid up to 1117 mg/L was produced. • Nitrogen and oxygen were the primary gaseous products in the off-gas stream. [ABSTRACT FROM AUTHOR]

[Display omitted] • Up to 98% of single-use PPE items was deconstructed. • Up to 547 mg/L ammonia was detected in the resulting reaction mixture. • Volatile fatty acids, primarily acetic acid up to 8974 mg/L was produced. • Carbon dioxide and oxygen were the main gaseous products in the off-gas stream. To minimise the transmission of the SARS-CoV-2 virus, there has been a substantial increase in the production and usage of synthetic personal protective equipment (PPE) globally. Consequently, single-use PPE have been widely adopted without appropriate regulations for their disposal, leading to extensive environmental contamination worldwide. This study investigates the non-catalytic hydrothermal deconstruction of different PPE items, including isolation gowns, gloves, goggles, face shields, surgical masks, and filtering-facepiece respirators. The selected PPE items were subjected to hydrothermal deconstruction for 90 min in the presence of 30-bar initial oxygen pressure, at temperatures ranging between 250 °C and 350 °C. The solid content in form of total suspended solids (TSS) was reduced up to 97.6%. The total chemical oxygen demand (tCOD) and soluble chemical oxygen demand (sCOD) decreased with increasing deconstruction temperature, and at 350 °C the lowest tCOD and sCOD content of 546.6 mg/L and 470 mg/L, respectively, was achieved. Short-chained volatile fatty acids were produced after 90 min of deconstruction, predominantly acetic acid at concentrations up to 8974 mg/L. Ammonia nitrogen content (NH 3 –N) of up to 542.6 mg/L was also detected. Carbon dioxide (CO 2) and unreacted oxygen (O 2) were the main gaseous by-products at up to 15.6% (w/w) and 88.7% (w/w), respectively. The findings suggest that non-catalytic hydrothermal deconstruction is a viable option to process and manage PPE waste. [ABSTRACT FROM AUTHOR]