Clean Fuel

A series of solid-acid catalysts with different content of components was prepared using the coprecipitation
method. These samples comprised modified γ-Al2O3 with phosphorus. The effects of various contents of
phosphorus (Al/P ratio from 0.5 to 3) have been investigated to determine an optimum one. The samples were
characterized using BET, TGA, XRD, and NH3-TPD techniques and were also tested in a fixed-bed flow
reactor under the same operating conditions (T ) 573 K, P ) 16 barg, WHSV ) 26.07 h-1). According to the
experimental results, phosphorus-modified catalysts have shown better performance compared to pure γ-alumina.
It was found that surface areas increase with an increase in the molar ratio of aluminum-to-phosphorus. It was
observed that aluminum phosphate samples with acidic sites whose acidity is very weak and/or moderate
exhibit the best catalytic performance and stability. The sample with molar ratio of Al/P ) 1.5 have exhibited
the best activity for methanol dehydration.

A series of solid-acid catalysts comprised of γ-alumina and modified γ-alumina with different of silica were prepared by co-precipitation method. The catalysts were characterized using XRD, TGA, NH 3 -TPD and BET techniques. Dehydration of methanol to dimethyl ether (DME) on solid-acid catalysts was studied in a fixed-bed reactor at the same operating conditions (T = 300°C, P = 16 bar, WHSV = 26.07 h − 1 ). According to the experimental results, silica-modified catalysts have shown better performance compared to the pure γ-alumina. It was found that surface areas increase with increasing silica loading. The results of NH 3 -TPD analysis showed that the surface acidity of aluminosilicate catalysts increases with increase in SiO 2 /Al 2 O 3 molar ratio. Also, it was found that the catalysts with highest portion of weak and/or moderate acid sites exhibit the best catalytic performance and stability. The sample with 3 wt.% silica loading has exhibited the best activity for methanol conversion.

A series of micro-mesoporous ZSM-5/MCM-41 composite molecular sieves were prepared by combining a microporous zeolite silica source with nano self-assembly methods, and characterized by SEM, TEM, XRD, N 2 adsorption and desorption, TPD of ammonia, and their catalytic performance for the dehydration of methanol to dimethyl ether (DME) in a fixed bed microreactor at atmospheric pressure. Among these catalysts, the ZSM-5/MCM-41 sample alkali-treated with 1.5 mol/L NaOH solution, in which the relative crystallinity of ZSM-5 and MCM-41 are 54.5% and 30.5%, respectively, gave the best activity (X MeOH > 80%) with 100% selectivity and a long lifetime in a wide range of temperature from 190 • C to 300 • C. From the characterization and activity data, the formation mechanism of the micro-mesoporous composite molecular sieves was proposed to be a liquid-crystal templating mechanism.

A series of solid-acid catalysts with different content of components was prepared using the coprecipitation method. These samples comprised modified γ-Al2O3 with phosphorus. The effects of various contents of phosphorus (Al/P ratio from 0.5 to 3) have been investigated to determine an optimum one. The samples were characterized using BET, TGA, XRD, and NH3-TPD techniques and were also tested in a fixed-bed flow reactor under the same operating conditions (T = 573 K, P = 16 barg, WHSV = 26.07 h−1). According to the experimental results, phosphorus-modified catalysts have shown better performance compared to pure γ-alumina. It was found that surface areas increase with an increase in the molar ratio of aluminum-to-phosphorus. It was observed that aluminum phosphate samples with acidic sites whose acidity is very weak and/or moderate exhibit the best catalytic performance and stability. The sample with molar ratio of Al/P = 1.5 have exhibited the best activity for methanol dehydration.

Inexpensive and low-Deep oxidative and extractive desulfurization of a simulated oil and a real diesel containing 1000 ppmw sulfur were studied under the catalysis of the proposed PAILs without additional carboxylic acid and extraction solvent in the system. The desulfurization efficiency in this study was influenced by both amount of PAILs and concentration of the produced peroxyacids from H2O2. Comparing to [Hnmp][HCOO], [Hnmp][CH3COO] and [Hnmp][CH3CH2COO] had a relatively higher extraction ability however the weaker acidic properties of them resulted in a lower activation of H2O2 to produce peroxyacids and finally led to a lower oxidative desulfurization (ODS) efficiency at a same condition. Additionally, the neutralization reaction may not be efficiently gone to right hand by weaker acids. The effects of main process variables were studied in detail. The highest desulfurization yield of 97% for BT and 99% for DBT and 4,6-DMDBT, were achieved using [Hnmp][HCOO] in the ODS system at temperature of 40 °C, H2O2/sulfur molar ratio of 10, VPAIL/Voil of 0.2 and reaction time of 90 min. The immiscibility of the proposed PAILs in this study with the oil phase caused easy separation of them after desulfurization. The possible ODS pathway was also proposed.

A series of solid-acid catalysts with different content of components was prepared using the coprecipitation
method. These samples comprised modified γ-Al2O3 with phosphorus. The effects of various contents of
phosphorus (Al/P ratio from 0.5 to 3) have been investigated to determine an optimum one. The samples were
characterized using BET, TGA, XRD, and NH3-TPD techniques and were also tested in a fixed-bed flow
reactor under the same operating conditions (T ) 573 K, P ) 16 barg, WHSV ) 26.07 h-1). According to the
experimental results, phosphorus-modified catalysts have shown better performance compared to pure γ-alumina.
It was found that surface areas increase with an increase in the molar ratio of aluminum-to-phosphorus. It was
observed that aluminum phosphate samples with acidic sites whose acidity is very weak and/or moderate
exhibit the best catalytic performance and stability. The sample with molar ratio of Al/P ) 1.5 have exhibited
the best activity for methanol dehydration.