ZIB

Hits per page

hits 1 - 2 | 2 hits

Sorting

Electronic Resource

The preparation of silica supported Pd catalysts: the effect of pretreatment variables on particle size (1992)

Zou, Weiqing ; Gonzalez, Richard D.

Springer

Catalysis letters 12 (1992), S. 73-86

add to mindlist on the mindlist

Details

ISSN: 1572-879X

Keywords: Silica supported Pd catalyst ; catalyst particle size ; CO chemisorption ; H2 chemisorption ; Pd dispersion ; transmission electron microscopy ; in-situ UV reflectance spectroscopy

Source: Springer Online Journal Archives 1860-2000

Topics: Chemistry and Pharmacology

Notes: Abstract The effect of pretreatment on the dispersion of Pd catalysts supported on silica has been studied. The catalysts were prepared from [Pd(NH3)4] (NO3)2 as the metal precursor at a pH = 9. The resulting catalysts were characterized using both CO and H2 chemisorption, transmission electron microscopy, and in-situ UV reflectance spectroscopy. Pretreatment in H2 resulted in poor Pd dispersions while pretreatment in He or Ar resulted in very high dispersions. Pretreatment in O2 resulted in moderate dispersions. The results are explained by considering the chemical structure of the adsorbed surface complex under different pretreatment conditions. The chemistry of the decomposition process is considered in detail.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1007/BF00767190

Permalink

Library	Location	Call Number	Volume/Issue/Year	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

Electronic Resource

Catalytic and interfacial aspects of enzymatic polymer synthesis in reversed micellar systems (1993)

Rao, A. Madhusudhan ; John, Vijay T. ; Gonzalez, Richard D. ; [et al.]

New York, NY [u.a.] : Wiley-Blackwell

Biotechnology and Bioengineering 41 (1993), S. 531-540

add to mindlist on the mindlist

Details

ISSN: 0006-3592

Keywords: horseradish peroxidase ; reversed micelles ; phenolic polymers ; enzyme kinetics ; Chemistry ; Biochemistry and Biotechnology

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology

Notes: The enzyme horseradish peroxidase, when encapsulated in reversed micelles, is capable of catalyzing the synthesis of phenolic and aromatic amine polymers. The synthesis of polyethylphenol is specifically considered in this article and is found to be extremely feasible in the micellar system. Polymer chain growth can be controlled to some degree by manipulating the ability of the solvent to sustain chain solubility; this is effectively done by adjusting the surfactant concentration. This results in a degree of control of polymer molecular weight. The synthesized polymer drops out of solution and can be easily recovered. © 1993 John Wiley & Sons, Inc.

Additional Material: 11 Ill.