an efficient method for the friedel–crafts acylation of a wide range of aromatic compounds in good to excellent yields under solvent-free conditions, using iron zirconium phosphate (zpfe) was investigated. the catalyst is easy to prepare and shows interesting catalytic properties. the catalyst was characterized by some instrumental techniques such as xrd, icp-oes, sem and tem. a wide variety of...

Ultrasound assisted phase-transfer catalyzed preparation of ethyl 2-(4-nitrophenoxy)acetate from the corresponding p-nitrophenol and ethyl 2-bromoacetate using the mild solid base, anhydrous potassium carbonate, under very mild conditions is reported. The solid-liquid reactions were performed in a batch reactor equipped with reflux condenser, and ultrasonic irradiations were introduced using an...

We describe a new catalyst for group IV nanowire heterostructures, based on alloying Ag with Au, that combines the ability to control catalyst phase and nanowire structure with good environmental stability. Compared to other alloy catalysts, we show a higher oxidation resistance of AgAu and more consistent crystal shapes and catalyst/nanowire orientation relationships during growth. We show tha...

Heterogeneous catalysts are promising for the transesterification reaction of vegetable oils to produce biodiesel and have been studied intensively over the last decade. Unlike the homogeneous catalysts, heterogeneous catalysts can be easily separated from reaction mixture and reused for many times. They are environmentally benign and could be easily operated in continuous processes. This revie...

palladium is the best metal catalyst for suzuki cross coupling reaction for synthesize of unsymmetrical biaryl compounds. but its high cost limits its application in wide scale. using of nanoscale particles as active catalytic cites is a good approach for reducing needed noble metal. by loading precious nanoparticles on magnetic nanocores as a support, recycling and reusing of catalyst will be ...

silica-bonded n-propyltriethylene-tetramine (sbnptt) was found as an efficient solid base for the synthesis of 2-amino-5-oxo-5,6,7,8-tetrahydro-4h-chromenes. chromene derivatives were obtained via the three-component condensation reaction of aromatic aldehydes, malononitrile, and dimedone at 80 oc under solvent-free conditions. the heterogeneous solid base showed much the same efficiency when u...

The development of new solid supports for palladium has received a lot of interest lately. These catalysts have been tested in a range of cross-coupling reactions, such as Suzuki–Miyaura, Mizoroki-Heck, and Sonogashira cross-coupling reactions, with good outcomes. Attaching the catalyst to a solid support simplifies the operations required in order to isolate and recycle the catalyst after a re...

Two-interconnected fluidized bed systems are widely used in various processes such as Fisher-Tropsch, hot gas desulfurization, CO2 capture-regeneration with dry sorbent, chemical-looping combustion, sorption enhanced steam methane reforming, chemical-looping hydrogen generation system, and so on. However, most of two-interconnected fluidized beds systems require riser and/or pneumatic transport...

The effects of preparative parameters on the surface basicity, composition, and transesterification activities of several Ca-La metal oxide catalysts were investigated. Four different preparation methods: ammonia-ethanol-carbon dioxide precipitation, physical mixing, impregnation, and coprecipitation, were studied. It was found that the ammoniaethanol-carbon dioxide precipitation method resulte...