English
Русский Adsorption of petroleum products with sunflower seed husk carbonate
Abstract
Оbjectives: the paper addresses the problem of environmental pollution by oil and petroleum products and substantiates the possibility of using sunflower seed husk carbonizate as an effective and economically affordable adsorbent for the fine purification of natural waters from oil contamination.
Methods. The physicochemical processes of sunflower seed husk pyrolysis in oxidative‑air and oxygen‑free (argon) atmospheres were investigated by thermal analysis (thermogravimetry and differential scanning calorimetry). Adsorption tests were carried out in accordance with GOST No. 33627-2015 using crude oil from the Yamal field and TS‑1 aviation kerosene. The selectivity of the adsorbent was evaluated in a model "oil‑water" system, and desorption characteristics were studied by gravimetry at room temperature.
Results. The main stages of thermo‑oxidative degradation and pyrolysis of sunflower seed husks were established: dehydration (up to 248-254 °C), release of volatile organic compounds (248-361 °C), and carbonization (361-820 °C); the yield of solid carbon residue in an inert atmosphere (13.2%) is 2.5 times higher than in air. The absorption capacity of the carbonizate was shown to reach 1.84 g/g for crude oil and 1.11 g/g for kerosene, which is comparable to known adsorbents from plant‑derived raw materials. The selectivity of the adsorbent in an aqueous medium was confirmed. A two‑stage nature of kerosene desorption was established: rapid loss of 9.3% within the first 1.5 hours, followed by slow desorption up to 48 hours.
Conclusions. It was found that sunflower seed husk carbonizate exhibits high thermal stability, competitive oil capacity, and selectivity towards petroleum products. The exclusion of the energy‑intensive activation stage significantly reduces the adsorbent production cost. The obtained results indicate the promise of using pyrolysis products of sunflower seed husks for developing effective means of oil spill remediation.
Methods. The physicochemical processes of sunflower seed husk pyrolysis in oxidative‑air and oxygen‑free (argon) atmospheres were investigated by thermal analysis (thermogravimetry and differential scanning calorimetry). Adsorption tests were carried out in accordance with GOST No. 33627-2015 using crude oil from the Yamal field and TS‑1 aviation kerosene. The selectivity of the adsorbent was evaluated in a model "oil‑water" system, and desorption characteristics were studied by gravimetry at room temperature.
Results. The main stages of thermo‑oxidative degradation and pyrolysis of sunflower seed husks were established: dehydration (up to 248-254 °C), release of volatile organic compounds (248-361 °C), and carbonization (361-820 °C); the yield of solid carbon residue in an inert atmosphere (13.2%) is 2.5 times higher than in air. The absorption capacity of the carbonizate was shown to reach 1.84 g/g for crude oil and 1.11 g/g for kerosene, which is comparable to known adsorbents from plant‑derived raw materials. The selectivity of the adsorbent in an aqueous medium was confirmed. A two‑stage nature of kerosene desorption was established: rapid loss of 9.3% within the first 1.5 hours, followed by slow desorption up to 48 hours.
Conclusions. It was found that sunflower seed husk carbonizate exhibits high thermal stability, competitive oil capacity, and selectivity towards petroleum products. The exclusion of the energy‑intensive activation stage significantly reduces the adsorbent production cost. The obtained results indicate the promise of using pyrolysis products of sunflower seed husks for developing effective means of oil spill remediation.