Electrodeposited Ni-Rich Ni–Pt Mesoporous Nanowires for Selective and Efficient Formic Acid-Assisted Hydrogenation of Levulinic Acid to γ-Valerolactone

Abstract

In pursuit of friendlier conditions for the preparation of high-value biochemicals, we developed catalytic synthesis of γ-valerolactone by levulinic acid hydrogenation with formic acid as the hydrogen source. Both levulinic and formic acid are intermediate products in the biomass transformation processes. The objective of the work is twofold: the development of a novel approach for milder synthesis conditions to produce γ-valerolactone and the reduction of the economic cost of the catalyst. Ni-rich Ni–Pt mesoporous nanowires were synthesized in an aqueous medium using a combined hard–soft-template-assisted electrodeposition method, in which porous polycarbonate membranes controlled the shape and the Pluronic P-123 copolymer served as the porogen agent. The electrodeposition conditions selected favored nickel deposition and generated nanowires with nickel percentages above 75 atom %. The increase in deposition potential favored nickel deposition. However, it was detrimental for the porous diameter because the mesoporous structure is promoted by the presence of the platinum-rich micelles near the substrate, which is not favored at more negative potentials. The prepared catalysts promoted the complete transformation to γ-valerolactone in a yield of around 99% and proceeded with the absence of byproducts. The coupling temperature and reaction time were optimized considering the energy cost. The threshold operational temperature was established at 140 °C, at which, 120 min was sufficient for attaining the complete transformation. Working temperatures below 140 °C rendered the reaction completion difficult. The Ni 78 Pt 22 nanowires exhibited excellent reusability, with minimal nickel leaching into the reaction mixture, whereas those with higher nickel contents showed corrosion.

Functionalization of casein and its use for preparing self-crosslinking protein-based materials

“…In the spectra of M-Cas the peaks with chemical shifts at 2.08 (s), 2.21 (t), and 2.58 (t) ppm were assigned to -CH 3 group, -CH 2 -(adjacent to the carboxyl group) and -CH 2 -(adjacent to the ketone group) of the LA attached to the protein backbone, respectively. 25,26 As expected, these peaks cannot be seen in P-Cas spectrum. Moreover, the area of the LA characteristic peak at 2.08 ppm relative to a reference signal (0.737 ppm) was 0.017, 0.065, and 0.045 for M-Cas A, B, and C, respectively (see Fig.…”

Catalytic valorisation of biomass levulinic acid into gamma valerolactone using formic acid as a H2 donor: a critical review

“…The group used hard-soft template-assisted electro-deposition method to engineer Ni 78 Pt 22 nanowires based on polycarbonate membranes that accommodate Ni–Pt mesoporous wires. Experiments showed that a TOF of 74 h −1 (100% conversion) and GVL selectivity near 99% were achieved at 140 °C during 120 min 110 . Ni and Cu cheap metals showed an excellent dispersion over SiO 2 support, featuring good catalytic activity in terms of hydrogenation of LA into GVL at a yield of 96% along with 4% Angelina lactone at 285 °C.…”

Assessing the Chemical Stability and Cytotoxicity of Electrodeposited Magnetic Mesoporous Fe–Pt Films for Biomedical Applications

“…Mesoporous materials have recently made significant contributions to enhancing surface-area-to-volume ratios as innovative, sophisticated materials that accommodate a soft-template process, micelle-assisted electrodeposition, that is not only essential but also simple to prepare. − Micelle-assisted electrodeposition involves new cooperative, synergetic means of synthesizing mesoporous nanomaterials in single-step electrochemical methods. ,, In those methods, micelles generated in the bath contribute to homogenizing the porous distribution during their growth, thereby allowing greater, more homogeneous distribution of pores in the material prepared. The presence of a block copolymer such as Pluronic P-123 in the aqueous bath has previously been demonstrated to be a soft inductive tool for forming mesoporous structures as effective pore inductors. − …”

“…30−34 Micelle-assisted electrodeposition involves new cooperative, synergetic means of synthesizing mesoporous nanomaterials in single-step electrochemical methods. 32,35,36 In those methods, micelles generated in the bath contribute to homogenizing the porous distribution during their growth, thereby allowing greater, more homogeneous distribution of pores in the material prepared. The presence of a block copolymer such as Pluronic P-123 in the aqueous bath has previously been demonstrated to be a soft inductive tool for forming mesoporous structures as effective pore inductors.…”