Phosphosulfonic acid as a multi solid site was easilyprepared from the reaction of ammonium dihydrogen phosphatewith chlorosulfonic acid in CCl4and for improved its catalyticactivity was supported nano Silica was extracted from husk ricecontains about 95% of Silica the size of extracted nano silica wasdetermined by SEM efficiency of this solid acid in four componentcondensation reaction of arom...

Heterogeneous esterification of 2-ethyl-1-hexanol and 2-ethyl hexanoic acid using AMBERLYST 15 as solid acid-catalyst in supercritical carbon dioxide (SC-CO2) has been studied. Effect of pressure (150, 200, and 250 bar), temperature (75, 110, and 140 C), flow rate of liquid CO2 (0.4, 0.6, and 0.8 mL.min), type of sample collection, and mole ratio of alcohol to acid (2:1, 1:1, and 1:2) on ester ...

We developed a kinetic model that describes a heterogeneous reaction system consisting of a solid substrate suspension for the production of D-amino acid using D-hydantoinase. As a biocatalyst, mass-produced free and whole cell enzymes were used. The heterogeneous reaction system involves dissolution of a solid substrate, enzymatic conversion of the dissolved D-form substrate, spontaneous racem...

Scientists engaged in heterogeneous catalysis often cite enzymes as their model catalysts. Enzymes can efficiently catalyze multistep processes that give various types of biomolecules. Remarkably, many enzymes combine two antagonistic catalytic functions, such as acid and base functions. Attracted by this challenge, several groups synthesized homogeneous catalysts that can successfully combine ...

Phosphosulfonic  acid  as a  multi  solid site  was  easily  prepared  from  the reaction of ammonium  dihydrogen phosphate with chlorosulfonic acid in CCl4and for improved  its  catalytic activity  was  supported  nano Silica was  extracted from  husk  rice  contains  about 95%  of  Silica the  size of  extracted nano silica was  determined  by  SEM  efficiency of  this solid acid in four comp...

Two highly efficient protocols for the production of bis-coumarins under solvent-free conditions have been introduced. The reaction of 4-hydroxycoumarin (2 eq.) with arylaldehydes (1 eq.) using phthalimide-N-sulfonic acid (PhtSA) or isatin-N-sulfonic acid (IsSA), as solid-acid catalysts, afforded the mentioned compounds with good to excellent yields in short times.Briefly, we have introduced tw...

An extrusion line has been installed and successfully operated at FNAL (Fermi National Accelerator Laboratory) in collaboration with NICADD (Northern Illinois Center for Accelerator and Detector Development). This new Facility will serve to further develop and improve extruded plastic scintillator. Recently progress has been made in producing co-extruded plastic scintillator, thus increasing th...

Polyethylene glycol was easily grafted to silica gel and used as a solid–liquid phase transfer catalyst in the reduction of aromatic nitro compounds. This silica-grafted polyethylene glycol is proved to be an efficient heterogeneous catalyst in the reduction of nitroarenes to the corresponding aromatic amines with zinc powder in water. The reduction reactions proceeded efficiently with exce...

3,4-ِdihydropyrano[c]chromene derivatives were synthesized using sulfonic acid functionalized silica (sio2-pr-so3h) as a highly efficient heterogenous solid acid catalyst via one-pot three-component condensation of aromatic aldehydes with malononitrile and 4-hydroxycoumarin in excellent yields.

Freshly prepared ZnO nanoparticles were used as an effective heterogeneous base catalyst for the synthesis of aryloximes. The conversion of arylaldehydes and arylketones into the corresponding oximes (up to quantitative yields) was achieved by simply mixing the liquid reactants and hydroxylamine hydrochloride with ZnO nanoparticles under solvent-free condition. The procedure was carried out und...