Adsorption Kinetics and Equilibrium of Model Fuel Desulfurization by Activated Carbon Synthesized from Rose Damascena Waste

Samples of low-cost activated carbons were synthesized from rose damascena waste by chemical activation using KOH as an activator with different KOH to rose damascena waste ratios (0.5, 1 and 2) as named ACR-0.5, ACR-1, ACR-2.  One sample was loaded with copper nanoparticles (ACR-2-Cu). The synthesized activated carbons have been characterized using FESEM (Field Emission Scanning electron microscopy), FTIR (Fourier transform infrared spectroscopy) and BET surface area analyzer. All activated carbon samples were used in desulfurization of a model diesel fuel composed of n-Heptane   4,6-dimethyldibenzothiophene (4,6-DMDBT) as sulfur containing compound. Results showed that ACRs with BET surface areas up to 1330-2155  were obtained. The BET surface areas and pore volumes increased with KOH to rose damascena waste ratio and Cu functionalization. More than 95% of 4,6-DMDBT adsorption capacity was reached in the first 10 min of adsorption experiment. The efficiency of sulfur removal by ACR was increased by enhancement the KOH to rose damascena waste ratio and by Cu functionalization. The 4,6-DMDBT adsorption capacity follows the order: ACR-2-Cu> ACR-2> ACR-1> ACR-0.5. The maximum adsorption capacity of ACR-2-Cu sample to 4,6-DMDBT was 24 mg S/gr adsorbent and the adsorption capacity was related to the volume of narrow micropores and Cu nanoparticles. The kinetic data was well described by pseudo-second and first-order kinetic models and the equilibrium adsorption data was well fitted to the Langmuir and Freundlich models to estimate the adsorption parameters.