Catalytic ceramic papers for environmental applications: the effect of natural borom compounds on the mechanical properties of diesel soot filters

S.A. LEONARDI; E.E. MIRÓ; M.A. ZANUTTINI; V.G. MILT; F.E. TULER

San Sebastián

Congreso; Congreso ICOSCAR 5; 2016

As it is well known, the transport activity causes the most serious environmental pollution. Theimplementation of Euro VI standard for heavy-duty vehicles in September 2014 has not only limited the mass emission of these pollutants, but also the number of particles emitted to 6.0 × 1011 particulates/km. Different types of structures have been considered for the development of filters, monoliths and foams being the most widely studied ones most used comercial filtersare flow-through type SiC monoliths. As an attractive alternative, the use of flexible substrates would allow the filtering element to adapt to any geometry or shell, providing a more versatile filter. The paper-type structure, composed of a network of fibers interconnected through pore-type spaces provides a beneficial reaction environment which favors the gas diffusion through the catalytic bed. Almost all preparations reported include the use of colloidal suspensions of Al2O3, CeO2, or ZrO2 as binders that join ceramic fibers by sintering after a calcination step. Recently, we reported the use of a novel type of compounds, borates, as binders, which sintered as the calcination temperature increased, thus joining ceramic fibers and giving the ceramic papers the necessary mechanical strength properties. Borates have the advantage of being less expensive and easily obtained.In this work we study the use of natural ulexite as binder to prepare ceramic papers. The catalysts(containing La, Ba , La-Co or Ba-Co) were incorporated so as to give ceramic papers the capacity of trapping NOx and burning soot under exhaust conditions.