Active Ti Species in TiCl3-Doped NaAlH4. Mechanism for Catalyst Deactivation

Towards a structure-performance relationship for hydrogen storage in Ti-doped NaAlH4 nanoparticles.

Hydrogen storage properties of Ti-doped nanosized (~20 nm) NaAlH(4) supported on carbon nanofibers were affected by the stage at which Ti was introduced. When Ti was deposited first followed by NaAlH(4), sorption properties were superior to the case where NaAlH(4) was deposited first followed by NaAlH(4). This was the result of both a smaller NaAlH(4) particle size and the more extensive cataly...

Catalyst deactivation

The fundamentals of catalyst deactivation are presented in this review. The chemico-physical aspects concerning the various deactivation causes (i.e. poisoning, sintering, coking, solid-state transformation, masking, etc.) have been analyzed and discussed, along with the mathematical description of the deactivation phenomena. # 1999 Elsevier Science B.V. All rights

Advances in Catalyst Deactivation and Regeneration

Precise Active Site Analysis for TiCl3/MgCl2 Ziegler-Natta Model Catalyst Based on Fractionation and Statistical Methods

In heterogeneous Ziegler-Natta catalysts for olefin polymerization, isolation of a single type of active sites is a kind of ambition, which would solve long-standing questions on the relationship between active site and polymer structures. In this paper, polypropylene produced by TiCl3/MgCl2 model catalysts with minimum Ti heterogeneity was analyzed by combined solvent fractionation and the two...

Heterogeneous Catalyst Deactivation and Regeneration: A Review

Deactivation of heterogeneous catalysts is a ubiquitous problem that causes loss of catalytic rate with time. This review on deactivation and regeneration of heterogeneous catalysts classifies deactivation by type (chemical, thermal, and mechanical) and by mechanism (poisoning, fouling, thermal degradation, vapor formation, vapor-solid and solid-solid reactions, and attrition/crushing). The key...