Fahai Cao

Alkylation of Toluene with 1, 3-Pentadiene over [bupy]BF4-AlCl3 Ionic Liquid Catalyst

Abstract The alkylation of toluene with 1, 3-pentadiene to produce pentyltoluene was carried out to obtain 2, 6-dimethylnaphalene, which is an important intermediate during the production of 2, 6-naphthalene dicarboxylic acid. Based on our previous work using anhydrous AlCl 3 as catalyst, [bupy]BF 4 -AlCl 3 ionic liquids were employed to catalyze the reaction of 1, 3-pentadiene with toluene. The experimental results show that [bupy]BF 4 -AlCl 3 ionic liquids are suitable for the reaction especially when the molar ratio of AlCl 3 to [bupy]BF 4 is 1.75 : 1, and the reaction could proceed at the temperature as low as 0°C. It could be as active as pure AlCl 3 , but much more environmentally friendly.

Methanol Conversion on SAPO-34 Catalysts Synthesized by Tri-templates

The effect of different combinations of a new tri-templating agent TEAOH/DEA/TEA, namely tetraethyl ammonium hydroxide (TEAOH)/diethylamine (DEA)/triethylamine (TEA), on the catalytic performance of SAPO-34 was investigated in MTO conversion. It was found that SAPO-34 and SAPO-5 are competing phases at TEA concentrations higher than 40 %. Pure SAPO-34 with high crystallinity, large BET surface area and small crystal size (0.8~1.4μm) was obtained at a low TEA concentrations. The combination of TEAOH/DEA/TEA strongly governed the acidity of crystals. TEAOH:DEA:TEA=0.67:0.67:0.67 gave an economical catalyst active in MTO reaction with 100 % methanol conversion, 89.39 % ethylene and propylene selectivity, a longest lifetime and a high coke capability of 24.2 wt %.

Alkylation of tolune with 1,3-pentadine over silica supported aluminum chloride catalyst in an extracting-distilling reactor

Abstract The alkylation of toluene with 1,3-pentadiene to produce pentyltoluene is designed to obtain 2,6-dimethylnaphalene for the monomer production of 2,6-naphthalene dicarboxylic acid. The possibility of the reaction is examined by the thermodynamics of the alkylation reaction using Thinhs group contributions method, and tested over silica supported aluminum chloride catalyst in a newly developed extracting-distilling reactor. The thermodynamics calculations results show that the alkylation reaction is exothermic and can proceed at 298-350K under normal pressure with an equilibrium constant higher than 106. Based on the thermodynamic calculation and the properties of the reactants and product, the extracting-distilling reactor was designed to allow 1,3-pentadiene to react with toluene at much lower temperature than the boiling point of toluene at the catalyst site. The alkylation product, which has a higher boiling point than that of toluene, is transferred from the catalytic site into the toluene ba...

Glycerol hydrogenolysis over a Pt–Ni bimetallic catalyst with hydrogen generated in situ

Using hydrogen generated in situ from aqueous phase reforming provides an efficient and economic route for glycerol hydrogenolysis. A Pt–Ni bimetallic catalyst supported on γ-Al2O3 has been prepared to catalyze the selective hydrogenolysis of glycerol to 1,2-propanediol, with glycerol conversion reaching 71.4% in 3 h. The significant promotion of conversion and selectivity could be explained by the formation of Pt–Ni alloy based on catalyst characterization. The effects of Pt/Ni ratio, reaction temperature and reaction time on the conversion of glycerol as well as product selectivity were also investigated.

Synthesis and Catalytic Activity of Ni/Ce-MCM-41 Mesoporous Catalysts for Hydrogen Production

Ce-containing MCM-41 mesoporous materials with large surface area and ordered pore structure system have been possible to be synthesized through a surfactant-assisted approach. The textural properties and structural regularity of the materials varied with the Si/Ce molar ratio. It is found that the band at 970 cm -1 in the FTIR spectrum of the Ce-MCM-41 mesoporous materials might be used as an indicator of the formation of the Ce-O-Si bond and its intensity as a measure of a degree of cerium ion substitution in the framework of Si-MCM-41. When Ni was loaded on the Ce-MCM-41 support, the Ni/Ce-MCM-41 catalysts show high catalytic activity which has strong temperature dependence. The methane conversion over these catalysts reached 60-75 % with a 100 % selectivity towards hydrogen.

The Weight Change of SAPO-34 Catalyst During MTO Process in TGA Reactor

The Thermax 700 thermo gravimetric analysis (TGA) instrument is introduced for the investigation of the weight change of SAPO-34 catalyst during methanol-to-olefin (MTO) process. By the use of a special sample basket with screen bottom, the TGA instrument can be viewed as fixed-bed reactor, while the weight change of SAPO-34 during MTO reaction can be recorded online. It is noticed that the SAPO-34 catalyst experiences a procedure of dehydration as furnace temperature rises; hence the weight increase of SAPO-34 during MTO reaction should be calculated based on the weight after dehydration. It is checked that the increase of weight is mainly coke ignore of adsorbates. In the range of 648∼773K temperature and 7.08∼35.9h -1 (WHSV) space velocity, the maximum coke deposition is roughly 25% independent of reaction condition. The coke formation experiences a stage of fast increase soon after reaction initiates, while slows down apparently after 18% coke is deposited on the catalyst. Higher temperature, space velocity and methanol partial pressure accelerate the coking rate. Temperature plays an important role in the type of coke formation, which can be distinguished directly by the colour of completely deactivated catalyst. The deactivated catalyst in lower temperature experiences a weight loss with partly recovery of catalyst activity as temperature rises in the hydrothermal atmosphere. The phenomenon of weight loss with catalyst regeneration will not occur as reaction temperature decreases for deactivated catalyst, as well as the different DTA curves for coke burning, are also evidences for the different type of coke formation on SAPO-34 catalyst in different reaction temperature.