Hydrothermal carbonization and adsorption of rice husk

In this study, the conversion of rice husk into clean solid fuel by hydrothermal carbonization and the adsorption efficiency by using it as an adsorbent were investigated. The effects of parameters on hydrothermal carbonization, reaction temperature (200, 220, 240 and 260 °C), holding time (0.5, 1, 2, 4 hours), solid/liquid ratio (7%) and pH were examined. This study focuses on optimizing the reaction parameters and evaluating the resulting hydrochar energy values and calculating the adsorption efficiencies of the formed hydrochars. At higher temperatures and holding times, carbon content increased after hydrothermal carbonization and H/C and O/C ratios decreased due to chemical transformation. The carbon content of hydrochars, which increased with both temperature and holding time, caused an increase in their energy value. The highest energy value was found to be 19,755 MJ/kg in a 4-hour experiment at 260 °C. The properties of hydrochar were determined by elemental analysis and proximate analysis. Dye removal from aqueous solution by adsorption method was studied and raw rice husk and hydrochars obtained by hydrothermal carbonization process at 200oC and 260oC were used as adsorbent. A shaking incubator was used in adsorption experiments. In order to prove the effectiveness of the study, the best efficiency was tried to be obtained at the optimum level by working depending on time, dose, speed and temperature. In the experiments, time (min), dose (mg), speed (rpm), temperature (0C) parameters were tested to purify the aqueous solution prepared with Methylene Blue dye. As a result of the study, for Methylene Blue; The optimum time was found to be 45 minutes, the optimum dose was 0.075 g/200 ml for PKham and PK200, 0.1 g/200 ml for PK260, the optimum speed was 200 rpm, and the optimum temperature was 25oC. Then , the isoterm suitable for the adsorption process was determined.