Pt Promotion of Zr Catalysts for Furfural-to-γ-Valerolactone Conversion [Dataset]

The valorization of biomass and its transformation into fuels are highly interesting due to the abundance of biomass and its almost neutral carbon emissions. In this article, we show the production of γ-valerolactone (GVL), a valuable product, from furfural (FF), a compound that can be easily obtained from biomass. This FF to GVL transformation involves a catalytic cascade reaction with two hydrogenation steps. Pt and/or Zr supported on sepiolite catalysts have been prepared and tested in the FF transformation reaction. A physical mixture of a Zr-based and a Pt-based catalyst has reached a yield to GVL of ca. 50% after 16 h at 180 °C. This performance largely exceeds that obtained by each of the single Pt or single Zr metal catalysts independently, showing a strong synergistic effect. These data suggest that each metal (Pt and Zr) plays an important and complementary role in different reaction steps. Furthermore, the physical mixture appears to be much more efficient than bimetallic Pt/Zr catalysts synthesized with the same amount of metals. The role of the type of acidity and the oxidation state of the surface platinum species on the catalytic performance has been discussed. Moreover, this reaction has been carried out in batch and continuous flow reactors, and a comparative study between the two operation modes has been undertaken. A certain correlation between the catalytic results obtained by both operation modes has been found. Description of methods used for collection/generation of data: Powder X-ray diffraction (XRD) patterns of catalysts were collected between 10 and 80 ° at 2θ using an Enraf Nonius FR590 sealed tube diffractometer (Bruker, Delft, The Netherlands) equipped with a monochromatic Cu Kα1 source (40 kV and 30 mA). In order to investigate the Lewis and Brønsted acidity, the adsorption–desorption of pyridine (Py) coupled with Fourier transform infrared spectroscopy (FTIR) was recorded in a Tensor 27 instrument (Bruker) with a Michelson interferometer. A He–Ne laser was used as an internal reference, and a DTGS infrared detector was also used. 64 accumulations were taken in transmission mode with a spectral resolution of 4 cm–1. The surface of the materials was cleaned by heating at 200 °C for 1 h and under a pressure of 0.1 mbar. Later, the samples were exposed to a pyridine atmosphere (200 mbar of pyridine vapor pressure) for 15 min at 50 °C. Physisorbed pyridine was eliminated by exposing the sample to a vacuum for 15 min after adsorption. The desorption was carried out at 100 and 200 °C, for 15 min each, under a vacuum. The transformation of FF into GVL in one pot was carried out in an autoclave reactor. The reactor has an internal part covered by a Teflon container of 25 mL, which fits with the steel walls. In a typical run, 0.25 mmol of FF was dissolved and mixed with 5 mL of 2-propanol. Later, 0.1 g of the catalyst was added. In the case of the reaction, where two different types of catalysts were used, 0.05 g of each catalyst was added to the reaction. After adding the catalyst, the reactor was purged with N2 for 1 min to remove oxygen, and later, it was sealed. The reactor was placed in a hot plate stirrer with a silicon bath at 180 °C and stirred at 500 rpm for the duration of the experiments. After the reaction was completed, the reactor was cooled in an ice bath for 15 min. The liquid products were collected by filtration for quantitative analysis. The products were analyzed by gas chromatography using a mod. 5890 GC instrument (Hewlett-Packard, Palo Alto, CA). Dodecane was used as an internal standard. The column used was an Agilent HP-1 column (30 m x 0.32 mm x 0.25 μm) coupled with a flame ionization detector (FID) at 240 °C and an injection port at 220 °C. The temperature program for the chromatographic cycle was as follows: (i) 35 °C isothermal for 30 min, (ii) a heating rate of 1.5 °C/min from 35 to 230 °C, and (iii) 230 °C isothermal for 30 min. Moreover, a gas chromatography–mass spectrometer was used (GC-MS5977A MSD-7890A, Agilent, Santa Clara, CA) to identify other reaction byproducts. The temperature program used was the same as that used in the GC-FID.Continuous flow reactions were carried out by using a homemade liquid-phase fixed-bed reactor (Figure S1). An HPLC pump (JASCO PU4080i) feeds the solution to the reactor (R1), which is placed in an oven (E2); at the exit of the reactor, there is a VCR filter (F2), followed by a backpressure regulator (BPR). Silicon carbide (SiC) as the desired diluent was loaded into the reactor together with 1 mL (between 0.42 and 0.52 g) of catalyst placed within the isothermal zone of the oven. Postreaction samples were analyzed via gas chromatography (Shimadzu GC-2010 Pro) using a flame ionization detector (GC-FID). The analysis method used was as follows: the injector was heated to 280 °C for the vaporization of the mixture, with N2 flow as the eluent of 1.2 mL/min and a split ratio equal to 30; an Agilent HP-5 column (diameter 0.32 mm, length 30 m) was placed inside a heated chamber at a controlled temperature through the following temperature program: 2 min of isotherm at 50 °C at a heating rate of 10 °C/min up to 250 °C, followed by an isotherm of 2 min at 250 °C; and an FID detector was heated to 250 °C for compound detection. To calculate the response factors, the moles, hence the molar flow, and finally the conversion and selectivity of the different products obtained, calibration curves of the principal commercial molecules involved in the cascade reaction (furfural (FF), furfuryl alcohol (FAL), α- and β-Angelica lactone (α-AnL, β-AnL), FE (furfuryl propyl ether), γ-valerolactone (GVL), and isopropyl levulinate (IPL)) were constructed. Response factors and retention times were identified: 5.2, 5.5, 5.8, 7.0, 7.2, 7.3, and 9.9 min.Methods for processing the data: Processed data are registered in files with extension csv.