Production of activated carbon from tea facility waste and almond shells by hydrothermal carbonization method

In this master's thesis, activated carbon was produced by hydrothermal method by using tea facility wastes obtained from Rize-ÇAYKUR facilities and almond shells taken from Elazığ- İçme region. For this purpose, the samples were subjected processing to in a hydrothermal carbonization (HTC) device at different times and temperatures. SEM, EDX and N2-BET analysis of the obtained carbonized materials were performed. Then, for the purpose of activation after hydrothermal carbonization, the samples were prepared at different KOH/Hydrochar ratios, placed in ash furnace in a covered metal crucible, and subjected to activation process at 600 °C for 4 hours. The products taken from the furnace were kept in HCl solution for 1 hour and then washed with distilled water until pH = 4. 5- 5 and filtered. Methylene blue absorption, SEM, EDX and BET analyzes were performed on the active carbon product remaining on the filter surface. In the methylene blue experiments, the extraction efficiency was calculated as 99. 2441 % in the A1 coded sample, which was activated at after setting it as KOH/Hydro Char=1/1. N2-BET analysis of the samples obtained by hydrothermal carbonization were performed. Accordingly, in the hydrothermal carbonization experiments carried out without using KOH, the highest surface area was obtained from the sample, which was a mixture of Tea facility waste + Almond shells, which underwent HTC treatment for 12 hours at 200 oC and the surface area of was determined as 20, 4984 m2/g. As a result of the experiments, it was seen that tea plant wastes were better carbonized than almond shells and higher extraction yields were obtained in methylene blue adsorption experiments. At the end of the activation processes, the surface area of the product obtained from the tea plant wastes is 887.41 m2/g and 874.77 m2/g depending on the KOH/Hydrochar ratio, while the surface area of the product obtained from the almond shells is found as 423.56 m2/g and 335.05 m2/g. Even, it was determined that the almond shells mixed with the tea plant wastes caused reductions in the surface area of the resulting product at the end of the activation processes.