استفاده از كربن حاصل از پسماند كشاورزي به عنوان جاذب در گوگردزدايي از سوخت مدل به روش يكپارچه‌شده‌ي استخراج مايع– مايع – جذب

The increasing concentration of sulfur compounds in fossil fuels, due to their destructive effects on the environment an‎d disrupting the balance of the life cycle of living organisms, has highlighted the need to develop new solutions to reduce sulfur content below permissible limits. In the present study, an integrated approach based on the combination of two extraction an‎d adsorption processes was presented for more effective sulfur removal. In this method, the adsorbent was dispersed in the extractant phase an‎d the extractant-adsorbent mixture was used to separate dibenzothiophene (DBT) from the model fuel. In the preparation of the model fuel, a solution of dibenzothiophene with a concentration of 1000 ppm in normal hexane was used. The adsorbents were porous carbon obtained from walnut an‎d pistachio shells (Cw an‎d Cp, respectively), whose surface was modified with 4 M nitric acid. The extractant phase was selec‎ted depending on the type of adsorbent, including acetonitrile:water, 70:30 for walnut carbon an‎d 60:40 for pistachio carbon. During the experimental stages, the effect of variables such as adsorbent amount, contact time, extractant phase to fuel ratio, DBT concentration an‎d fuel volume on sulfur removal efficiency was investigated an‎d optimal values were determined. The results showed that the sulfur removal efficiency in the simple extraction process with the aforementioned extractant phases (acetonitrile:water 70:30 an‎d 60:40) was about 19 an‎d 12.5 percent, respectively. However, the combination of the two extraction an‎d adsorption processes significantly increased the sulfur removal efficiency; so that it reached 85.5 an‎d 83 percent for the modified adsorbents obtained from walnut an‎d pistachio (m-Cw an‎d m-Cp), respectively. Also, by separating the adsorbent from the extractant phase without the need for a distillation process, it was possible to reuse the adsorbent up to three times for m-Cw an‎d up to four times for m-Cp, which is of great importance from an environmental perspective

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