Synthesis of copper catalysts by coprecipitation of Cu(II) and chitosan onto alumina
Advancing the chemical engineering fundamentals
Catalysis (T2-13P)
Keywords: Copper, Chitosan, Alumina, Adsorption, Coprecipitation
Pollution levels of the ecosystem have been dramatically enlarged since industrial activity has increased. Released industrial wastes with high concentrations of heavy metals need to be treated by specific and environmentally friendly processes for their separation. The elevated metal concentration on industrial effluents represents a green problem because of their high toxicity, separation difficulties and accumulative behaviour in water. Industrial and mining wastewaters are important sources of pollution of heavy metals, from which copper is extensively used in electrical industries, fungicides and in anti-fouling paints.
Methods for metallic removal like membrane separation, chemical precipitation, ion exchanger and adsorption have been used effectively. Moreover, the use of a different technique like co-precipitation supports the recovery of heavy metals promoting the formation of metal complexes with additional catalytic properties.
One of the polymers more frequently used for metal removal is Poly (D-glucosamine) (Chitosan), which is a natural material produced by the alkaline deacetylation of chitin. Chitin is present in exoskeletons of crustaceans, cuticles of insects and cell walls of most fungi. Moreover, Chitosan is known as a good metal adsorbent because its –NH2 and –OH radicals provide coordination sites for metal ions, so that the use of Chitosan as a promoter of a better metal complexation seems to be attractive for the synthesis of copper catalysts.
The formation of metal complexes with catalytic activity can be improved by increasing the stability of the final product and by enlarging the catalytic lifetime, consequently the use of a support like alumina provides better catalytic configuration, even more remarkable when the reaction to be tested is an oxidation of a recalcitrant compound.
The aim of this research is to produce and improve a catalytic material obtained from wastes to treat industrial effluents with high levels of phenolic compounds. The catalytic performance is tested under room conditions and the results show the easy separation and recovery of the catalyst. The use of alumina as support of the chitosan-copper complex decreases the catalytic leaching.
Finally, the use of Chitosan to remove copper ions from aqueous media presents effective values that promote the well co-precipitation onto alumina and provide high catalytic activity to the final product.
See the full pdf manuscript of the abstract.
Presented Wednesday 19, 13:30 to 15:00, in session Catalysis (T2-13P).
