Evaluation of physicochemical and phytotoxic properties of WCO-based composites with natural additives

Currently, global consumption of vegetable oils for food purposes exceeds 200 million tons per year. Hazardous waste frying oil has become a fully valuable, environmentally friendly raw material with a wide range of industrial applications. Solid materials based on waste cooking oil (WCO) are becoming increasingly popular due to their easy production technology, availability of raw material, and low cost. Waste cooking oil can be used to produce materials used in the construction industry. In the present study, the manufacturing process of oil composites reinforced with natural additives such as nut shells, pistachios, and shellfish shells was optimized and their physicochemical and phytotoxic properties were determined. The absorbability of the obtained oil composites ranged from 3.1 to 10.3%. The maximum growth inhibition of 82% was recorded for the underground part of Sinapis alba for soil soaked in a solution obtained by leaching oil composites obtained at 185 °C (catalyst: catalyzed oil ratio equal to 0.24). Lowest growth - 63% for Sorghum saccharatum grown on a sponge soaked in a solution obtained by leaching oil composites was obtained at 210 °C (catalyst:catalyzed oil ratio equal to 0.13).