platinum extraction from different secondary sources has been experimentally tested by many researchers. in this article, dissolution of platinum in aqua-regia solution from two types of spent catalysts (reforming and nitric acid production) was kinetically studied. a variety of kinetic models for heterogeneous solid-liquid reactions, including homogeneous diffusion model, shrinking core model,...

The rapid separation and efficient recycling of catalysts after a catalytic reaction are considered important requirements along with the high performances. In this view, although heterogeneous catalysis is generally less if compared to homogeneous type, it preferred since benefits from easy recovery catalyst. Recycling using traditional methods such as extraction, filtration, vacuum distillati...

RECYCLING OF SPENT CATALYSTS FOR ENVIRONMENTAL PROTECTION

The results of studies on the separation of platinum(IV) ions by solvent extraction from aqueous solutions after leaching of spent catalysts have been reviewed. The following processes have been discussed: acid leaching of spent catalysts and solvent extraction of platinum(IV) ions by using organophosphorous acids, amines and oximes as the extractants. In hydrometallurgical leaching of spent au...

TÜBİTAK Marmara Research Center, Chemistry Institute, 41470 Gebze, Kocaeli, Turkey Email: [email protected] Activated carbon-supported palladium catalysts are liable to progressive deactivation even in the absence of any gaseous contaminants during the oxidation of hydrogen under ambient conditions. The high value of palladium coupled with environmental considerations means that n...