The
use of available renewable sources of raw materials for the
production of various organic compounds has long been undoubted and
recognized throughout the world. However, the development of efficient
“green” catalytic technologies for the processing of
bioavailable compounds, namely, the synthesis of catalysts and the
selection of optimal process conditions, has become a real challenge
for researchers nowadays. In this work, 2,5-bis(hydroxymethyl)furan,
an intermediate for the production of a number of biobased polymer
materials, was obtained by hydrogenation of 5-hydroxymethylfurfural
in a yield close to quantitative at room temperature and atmospheric
pressure in the presence of a catalytic system with 1% wt of platinum
as an active phase supported on ceria–zirconia mixed oxide.
On the low-loaded 0.25% Pt/CeO2–ZrO2 catalyst,
the yield of the desired alcohol as high as 87% has been achieved
after a slight increase of H2 pressure from 0.1 to 0.5
MPa.
The bimetallic Crn+/Pd0 nanoparticles have been synthesized for the first time by a two-step redox method. The method includes the deposition of Pd0 nanoparticles on the surface of SiO2 and TiO2 carriers followed by the deposition of Crn+ on the surface of Pd0 nanoparticles using the redox procedures, which are based on the catalytic reduction of Crn+ with H2 in aqueous suspensions at ambient conditions. Transmission (TEM) and scanning (SEM) electron microscopy, X-ray photoelectron spectroscopy (XPS), Fourie-transformed infrared spectroscopy of adsorbed CO (FTIR-CO), and CO chemisorption studies were performed to characterize the morphology, nanoparticle size, element, and particle distribution, as well as the electronic state of deposited metals in the obtained catalysts. A decrease in nanoparticle size from 22 nm (Pd/SiO2) to 2–6 nm (Pd/TiO2) makes possible deposition of up to 1.1 wt.% Cr most likely as Cr3+. The deposition of CrOx species on the surface of Pd nanoparticles was confirmed using FTIR of adsorbed CO and the method of temperature-programmed reduction with hydrogen (TPR-H2). The intensive hydrogen consumption in the temperature ranges from −50 °C to 40 °C (Cr/Pd/SiO2) and from −90 °C to −40 °C (Cr/Pd/TiO2) was first observed for the supported Pd catalysts. The decrease in the temperature of β-PdHx decomposition indicates the strong interaction between the deposited Crn+ species and Pd0 nanoparticle after reduction with H2 at 500 °C. The novel Crn+/Pd/TiO2 catalysts demonstrated a considerably higher activity in selective hydrogenation of phenylacetylene than the Pd/TiO2 catalyst at ambient conditions.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.