Adsorptive Desulfurization of Liquid Fuels Using Na-Bentonite Adsorbents

Abstract

In this work, model fuel (Thiophene in hexane) was treated for sulfur removal by adsorptive desulfurization method using modified bentonite with sodium (Na-B) adsorbent. Batch and continuous mode were used in this study. Several operating parameters such as initial thiophene concentration of 250 to 2000 mg/L , adsorbent dose 0.1 to 0.8g/ml were studied for sulfur removal %. Also a comparison between raw and modified bentonite was performed in this study. In continuous mode, a packed bed of Na-B adsorbent column was used at constant initial thiophene concentration and liquid hourly space velocity (LHSV) to study the breakthrough curve of thiophene. The results showed that Na-B adsorbent was better than raw bentonite in removal of sulfur components. The removal percentages was 67,75,87,and 91% for 500 mg/L initial thiophene concentration using adsorbent dose o.1, 0.2, 0.4 and 0.8g/ml respectively , and 87, 75, 57, and 53% for adsorbent dose of 0.2 g/ml using initial thiophene concentration of 250, 500, 1000, and 2000 mg/L respectively. It was concluded that when increase the dose of adsorbent, the removal of sulfur increase , and when increase the initial concentration the removal decrease.

Desulfurization of a Model Liquid Fuel by Adsorption over Zinc oxide/Activated Alumina Assisted with Ultrasonication

“…Figure 7F reveals that increasing the sonication time has a positive effect on improving the percentage of sulfur removed until reaching its highest value at 40 minutes to facilitate the adsorption of sulfur molecules, and thus the contact time is reduced to reach the state of equilibrium, so the contact time and sonication time are considered complementary to each other. This trend has been confirmed by previously published data of [37,40].…”

“…Figure 7A depicts the influence of the initial sulfur concentration on the removal process, which indicates that increasing the initial concentration decreases the sulfur component's removal rate. This trend is because each ZnO loaded-adsorbent has a finite number of active sites on its surface that become saturated at a particular sulfur concentration [39,40].…”

“…The physicochemical changes are primarily caused by the production of extreme temperature (~10,000 K) and pressure (~1000 atm) conditions at the pico‫ـ‬scale as a result of the cavitation process's implosion of cavities, which can then cleave the molecules. This makes it easier for molecules to flow through the pores of the adsorbent substance [37,40].…”

“…Figure 7D demonstrate a growing trend in the removal process with increasing duration and adsorbent dosage. It's a well-established fact that as time passes, more adsorption sites become accessible, causing absorption rates to rise [40,43].…”

Isothermal and Kinetics Investigation of Dibenzothiophene Removal from Model Fuel by Activated Carbon Developed from Mixed Date Seed and PET Wastes

“…Also, most of the adsorbents can be easily regenerated, either through thermal processes or solvent washing (Yaseen et al,2021;de la Cruz et al, 2020). To date, multiple adsorbents were applied in the ADS, like metal-organic frameworks (An., 2018), carbon materials (Saleh et al, 2018;Mohammed-Taib and Fadhil., 2021;Alhamed and Bamufleh, 2009), metal oxides (Hou et al, 2018), clays (Ali., 2018), and zeolites (Song et al, 2013). Among the carbon derived materials that was widely implemented in the ADS process is the AC as an outcome of its elevated surface area besides its surface, which owns multiple effective functional groups, which take part in the ADS processes.…”