A further catalysis mechanism study on Amberlyst 35 resins application in alkylation desulfurization of gasoline

Enhancement of the hydrophilic feruloyl glycerol synthesis using A-35 as a catalyst and its functional characteristics

Feruloyl glycerol (FG) is the hydrophilic ester of ferulic acid (FA), which has a high solubility in water and a strong ability to resist ultraviolet (UV) radiation. In this work, several solid acids were used as novel economical catalysts and FA was used as a cheap substrate for FG preparation. The effects of reaction variables on the esterification of FA with glycerol were investigated and optimized by response surface methodology (RSM). Results showed that a cheap solid acid cation exchange resin A-35 showed the best performance for esterification. The reaction conditions were optimized by RSM as follows: 15 : 1 (glycerol/FA) substrate molar ratio and 14% catalyst loading at 90 °C for 7 h. The maximum FG yield (98.50 ± 0.58%) was achieved under the optimized conditions. The activation energy of the esterification was 53.71 kJ mol^-1. The results of UV absorbance showed that FG had good anti-UV activity and photostability, which can be used as a potential antioxidant and UV absorber in food and sunscreen products.

Synthesis of Lipophilic Caffeoyl Alkyl Ester Using a Novel Natural Deep Eutectic Solvent

In this work, a novel method for lipophilic caffeoyl alkyl ester production was developed using a natural deep eutectic solvent (DES) consisting of choline chloride and caffeic acid (CA) as the caffeoyl donor. Cation-exchange resins were used as the catalyst to catalyze the esterification of fatty alcohols with the DES. Effects of the caffeoyl donor and reaction variables were investigated. Reaction thermodynamics were also analyzed. The results showed that the lipophilic caffeoyl alkyl ester production can be enhanced using the DES as the caffeoyl donor, and cation-exchange resin A-35 showed the best catalytic activity for the reaction. Under the optimized conditions (85 °C, stearyl alcohol/CA 8:1 (mol/mol), A-35 load 5% and 24 h), the maximum octodecyl caffeate (OC) yield (90.69 ± 2.71%) and CA conversion (95.17 ± 2.76%) were obtained with the DES as the caffeoyl donor, which were much higher than those obtained with solid CA as the caffeoyl donor (OC yield 40.97 ± 2.37% and CA conversion 44.26 ± 1.69%). The activation energy of CA conversion (67.57 kJ/mol) with the DES was lower than that with solid CA (90.19 kJ/mol). In addition, the mass transfer limitation can be decreased with the DES. Compared with solid CA as the caffeoyl donor, a fast reaction rate and low mass transfer limitation were obtained using the DES as the caffeoyl donor.

Simultaneous removal of sulfides and benzene in FCC gasoline by in situ hydrogenation over NiLaIn/ZrO2-r-Al2O3

The ZrO₂-r-Al₂O₃ composite was developed and co-modified with nickel, lanthanum and indium species by the impregnation method. A fixed-bed reactor was utilized to investigate the activity of the resulting catalysts in the removal of sulfides and benzene in fluid catalytic cracking gasoline. The resultant samples were characterized using XRD, TEM, XPS, TGA, H₂-TPR, NH₃-TPD and N₂ adsorption/desorption techniques. XRD analysis indicated no agglomeration of Ni and La species, in good agreement with the TEM image. Only under the suitable conditions of a metal loading of 15%, a reaction temperature of 423K, a reaction time of 60min, a space velocity of 3h^-1, and a reaction pressure of 1MPa, could the desulfurization ratio, the debenzolization ratio, and selectivity of benzene to dimethylbutane and toluene reach 100%, 19.9%, 48.9% and 50.9%, respectively, and research octane number of the product increased by 2 units and sulfur content reached "Zero". The catalyst was actively involved in the in-situ hydrogenation under mild conditions and used for 30h with no loss in activity. This remarkable behavior makes the NiLaIn/ZrO₂-r-Al₂O₃ family a potential candidate for industrial application as catalysts in the clean fuel.