Reforming Methane with CO2 over Hierarchical Porous Silica-Supported Nickel Catalysts Modified with Lanthanum Oxide

Hierarchical porous silica-supported nickel catalysts modified with different amounts of lanthanum (La) were synthesized via “one-pot” method using cetyltrimethylammonium bromide as template, urea precipitant, and tetraethyl orthosilicate silica source. Their catalytic performances evaluated in dry reforming methane under conditions (La loading, reaction temperature, time on stream). The spent extensively characterized by ICP, physisorption, chemisorption, XRD, TPR, XPS, HAADF-TEM, TPH, Raman’s spectroscopy, TG analysis. impact amount the performance, sintering, carbon deposition was discussed. Compared to unmodified catalyst, La promoter induced nanoparticles larger crystallite sizes weakened metal-support interaction well formation 1 : nickel-phyllosilicate, leading metal sintering increasing order Ni1.5La/SiO2 < Ni3.0La/SiO2 Ni4.5La/SiO2. exhibited better resistance, which significantly enhanced content. Despite this, stability increased following sequence Ni4.5La/SiO2 Ni1.5La/SiO2. displayed best at 750°C within 10 h test, CH4 conversion dropping from 61.3 58.0%. deactivation reason for mainly deposition, while that sintering. These results emphasized activity NiLa/SiO2 depended two important factors, particles size nickel, providing necessity sufficiency balance attributes.