Supported olefin polymerization catalysts can prevent reactor-fouling problems and produce uniform polymer particles. Constrained geometry complexes (CGCs) have less sterically hindered active sites than bis-cyclopentadienyl metallocene catalysts. In the literature, micrometer-sized silica particles were used for supporting CGC catalysts, which might have strong mass transfer limitations. This ...

Through the strategic design of ligands based on amino acids, structural diversity in chiral coordination architectures of CuII is demonstrated with six new examples: {[Cu(L-HTyrbenz)2]·CH3OH·H2O}n (1), {[Cu(L-HSerbenz)2]·3H2O}n (2), {[Cu(L-HTyrthio)2]·H2O}n (3), [Cu(L-HTyr4-pyr)2(H2O)]·2H2O (4), [Cu(L-HSerthio)2(H2O)] (5), and [Cu(L-Phethio)2(H2O)]·3H2O (6) [where L-H2Tyrbenz = L-N-(benzyl)-ty...

Model catalyst surfaces, consisting of vapordeposited metal nanoparticles supported on a planar oxide support, can help to link reactivity studies on well-defined single crystal surfaces with those conducted on high-surface area supported catalysts. When coupled with near atmospheric pressure kinetic and spectroscopic techniques, these well-defined model catalyst surfaces represent a useful app...

The effect of eggshell particles on the mechanical properties of epichlorohydrin crosslinked chitosan/eggshell composites had been studied. The content of eggshell particles in each composites was varied from 2.5 to 13.4% (w/w). The tensile strength was 60% improved, compared to the control chitosan. The composite with 13.4% (w/w) content of eggshell particles showed the optimum tensile strengt...

Bimetallic Pt-V supported by Gamma-alumina is used to observe the changes of nheptanewhen passed over this catalyst. The Pt concentration was kept constant at0.1wt% while the concentration of the vanadium was 0.5wt%. The activity andselectivity of catalyst have been determined under conditions at 450-500 degreescentigrade and 15-30 attn. The experimental results show that the addition of second...

Magnetic nanoparticle-supported sulfanilic acid (MNPs-PhSO3H) has been used as an efficient catalyst for the preparation of 1,4-diazepines containing tetrazole ring. The catalyst has been characterized by FT-IR (Fourier-transform infrared spectroscopy), SEM (scanning electron microscope), XRD (X-ray diffraction) and VSM (vibrating-sample magnetometer). The present synthetic protocol provides se...

Catalyst productivity and selectivity to C5+ hydrocarbons are critical design criteria in the choice of Fischer-Tropsch synthesis (FTS) catalysts and reactors. Cobalt-based catalysts appear to provide the best compromise between performance and cost for the synthesis of hydrocarbons from CO/H2 mixtures. Optimum catalysts with high cobalt concentration and site density can be prepared by control...

An eggshell is a porous microstructure that regulates the passage of gases to allow respiration. The chick embryo and its circulatory system enclosed by the eggshell has become an important model for biomedical research such as the control of angiogenesis, cancer therapy, and drug delivery test, because the use of embryo is ethically acceptable and it is inexpensive and small. However, chick em...

Silica-supported tantalum clusters (on average, approximately tritantalum) were formed by the treatment, in either H(2) or ethane, of adsorbed Ta(CH(2)Ph)(5); the supported catalyst is active for ethane conversion to methane and propane at 523 K, with the used catalyst containing clusters of the same average nuclearity as the precursor.

The front-end process integration of the selective acetylene hydrogenation provides several advantages over tail-end option. But extensive knowledge and reaction kinetics are required. This work combines ideal conditions advanced TEMKIN reactor in a laboratory plant for gradient-free kinetic analysis eggshell catalyst under industrially relevant conditions. With this system an industrial state ...