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The present work is an experimental investigation of commercial diesel fuel liquid desulfurization via adsorption under mild conditions. The sorbent employed was a commercial high surface area activated carbon (AC) and studies involved both lab-and pilot-scale experiments performed in dedicated fixed bed setups. Under lab-scale conditions, maximum sulfur removal measured exceeded 90%, while according to breakthrough curves obtained the total sulfur content remained below 2 ppmw for up to 20-22 ml processed diesel/g AC. Process scaling-up by a factor of 15 showed a moderate negative effect, with the respective breakthrough fuel amount (total sulfur ≤ 2 ppmw) being approximately 15-17 processed fuel/g sorbent. Several sorbent regeneration strategies were studied under lab-scale conditions. The one with the highest restoration of initial (i.e. fresh state) AC performance involved heating under vacuum (200 mbara) up to 200 o C and subsequent washing of the material with a binary organic solvent. The amount of solvent required was 50-55 ml /g sorbent. However, even under such conditions, desulfurization performance was only partially restored upon repeated desulfurization/regeneration cycles. From the 2 nd and up to 7 th cycle, desulfurization efficiency of the material was essentially stable but from cycle number 8 and on further performance degradation was identified. Based on fresh/regenerated sorbent post analysis, it was found that cycle-to-cycle degradation was due to gradual decrease of the sorbent's surface area, mainly attributed to residual amounts of diesel-derived species remained in its structure thereby partially blocking its porosity. The main properties of processed fuel remained essentially unaffected, however removal of di-and poly-aromatic compounds was notable.

Recently, metal oxides and magnesium hydroxide nanoparticles (NPs) with high surface-to-volume ratios were shown to possess antibacterial properties with applications in biomedicine and agriculture. To assess recent observations from field trials on tomatoes showing resistance to pathogen attacks, porous micron-scale particles composed of nano-grains of MgO were hydrated and sprayed on the leaves of healthy tomato (Solanum lycopersicum) plants in a 20-day program. The results showed that the spray induced (a) a modest and selective stress gene response that was consistent with the absence of phytotoxicity and the production of salicylic acid as a signalling response to pathogens; (b) a shift of the phylloplane microbiota from near 100% dominance by Gram (−) bacteria, leaving extremophiles and cyanobacteria to cover the void; and (c) a response of the fungal leaf phylloplane that showed that the leaf epiphytome was unchanged but the fungal load was reduced by about 70%. The direct microbiome changes together with the low level priming of the plant’s immune system may explain the previously observed resistance to pathogen assaults in field tomato plants sprayed with the same hydrated porous micron-scale particles.