| 1. Benzene Alkylation with 1-Dodecene over Solid Acid catalystsLinear alkylbenzene (LAB), an intermediate used in the detergency sector, is produced industrially by benzene alkylatiori with higher n-alkenes basically in the range of C10 to C13 in the presence of anhydrous HF or AlCl3 as catalyst. In this work. Benzene alkylation with 1-dodecene was carried out over solid acid catalysts such as H-ZSM-5, H-Y, and H-mordenite zeolites, respectively in a batch reactor at 120 ~ 140 ? and 10 atm. Reaction parameters such as temperature and molar ratio of benzene to 1-dodecene were also investigated. It is observed that the conversion of 1-dodecene is. in the order of HZSM-5 < H-MOR < H-Y < USH-Y, proportional to the pore apertures of the zeolites, which evidences that pore size of zeolite is an important factor in controlling activity. Among all the catalysts applied, H-mordenite shows the highest selectivity for 2-phenyl dodecane, owning to its medium pore size and one-dimensional pore opening system. Depending on the catalyst amount (from 0.5 g to 1.0 g) and the molar ratio of benzene to 1-dodecene (from 7 to 10), the conversions of 1-dodecene vary in the range from 63.8% to 100%. The selectivity for 2-phenyl dodecane can reach up to 78.2% with 100% 1-dedecene conversion, which makes it applicable in LAB production. Furthermore, H-mordenite zeolite was modified by solid-ioh-exchange with Mg2+ and Fe 3+ ions and acid dealumination, which lead to the increase of selectivity for 2-phenol isomer and decrease of conversion of 1-dodecene as well. The acidic properties of mordenite zeolites were characterized by pyridine adsorbed FT-IR, and it is found that both strong Bransted and Lewis acid sites are favorable for this reaction.2. Phenol Iso-propylationIso-propylphenols are useful intermediates in the synthesis of various products such as synthetic resins, adhesives, agricultural chemicals and pharmaceuticals. It is known to prepare such products via the alkylation of phenol with propylating agents in the presence of Friedel-Craft type catalysts such as AlCl3, ZnCl2, H3PO4, and HCl,with low conversion and selectivity. Furthermore, the use of these catalysts gives rise to many problems concerning handling, catalyst recovery, safety, corrosion, and waste disposal.In this work, the alkylation of phenol with propylene over several solid acid catalysts such.as HZSM-5 with different silica to alumina ratio, H-Beta, USH-Y and ?-Al2O3 has been studied. The conversions of phenol over H-Beta and USH-Y are much higher than that over HZSM-5 due to their different pore structure and size, which results in the , different diffusion rate of reactants and products. Isopropylphenol ether is found to be formed over all above catalysts at low temperature, whereas, at higher temperature isopropylphenol ether is not detected and phenol alkylation occurrs exclusively at the carbon atom of aromatic ring. Furthermore, H-Beta and USH-Y show selectivity for ortho-isomer and HZSM-5 exhibits moderate selectivity for para isomerApart from shape selectivity taking effect in phenol alkylation with propylene over HZSM-5 zeolites, acidic properties, i.e. acid strength and acid density also influence product distribution. It is observed that selectivity for para isomer is improved with the increase of silica to alumina ratio in the range from 30 to 150. Meanwhile, Cs+ ion exchange of HZSM-5 with silica to alumina ratio of 30 and 80 leads apparently to the increase of selectivity for para-iso-propylphenol, respectively. Solid-state 31P NMR of the probe'molecule of trimethylphosphine oxide (TMPO), combined with NH3-TPD were used to characterize the acidic properties of ZSM-5s. It is found that para-isopropylphenol is favorable for moderate acid site.3. Catechol t-Burylation4-tert-butylcatechol(4-TBC) and its derivatives are used as raw materials for the synthesis of several polymerization inhibitors, dye developers, Pharmaceuticals, and agricultural chemicals. In this study, t-butylation of catechol with t-butyl alcohol as alkyla...
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