Zirconium phosphate glycine diphosphonate nanosheets (ZPGly) have been used as support for the preparation of solid palladium nanoparticles, namely Pd@ZPGly. Thanks to the presence of carboxy-aminophosponate groups on the layer surface, ZPGly-based materials were able to stabilize a high amount of palladium (up to 22 wt %) also minimizing the amount of metal leached in the final products of representative important cross-coupling processes selected for proving the catalysts' efficiency. The catalytic systems have been fully characterized and used in low amounts (0.1 mol %) in the Suzuki-Miyaura and Heck cross-couplings. Moreover, the protocols were optimized for the use of recoverable azeotropic mixtures (aq. EtOH 96% or aq. CH 3 CN 84%, respectively) and in the flow procedure allowing one to isolate the final pure products, without any purification step, with very low residual palladium content and with a very low waste production.

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One of the primary targets for the new lignocellulosic feedstock-based biorefinery is the simultaneous valorization of holocellulose and lignin. Acidified organosolv treatment is among the most promising strategy for recovering technical lignin, water-soluble hemicellulose, and cellulose pulp with increased accessibility to hydrolytic enzymes. In this work, a design-of-experiment (DoE) approach was used to increase the cellulose recovery, digestibility, and the delignification of Cynara cardunculus L. feedstock. In the first treatment, the milled biomass was subjected to microwave-assisted extraction using an acidified GVL/water mixture to separate lignin and hemicellulose from cellulose. In the second treatment, the cellulose pulp was hydrolyzed by cellulolytic enzymes to demonstrate the enhanced digestibility. At the optimal condition (154 °C, 2.24% H2SO4, and 0.62 GVL/water ratio), the cellulose pulp showed a cellulose content of 87.59%, while the lignin content was lower than 8%. The cellulose recovery and digestibility were equal to 79.46% and 86.94%, respectively. About 40% of the initial hemicellulose was recovered as monosaccharides. This study demonstrated the effectiveness of the two-step organosolv treatment for biomass fractionation; however, as suggested by DoE analysis, a confirmative study at a low temperature (<154 °C) should be performed to further increase the cellulose recovery.

A gold‐incorporated SBA‐15 catalyst was prepared by a solvent‐free ball‐milling approach. The catalyst showed high reactivity and selectivity in the reduction of a variety of nitroarenes to anilines operating in absolute EtOH with NaBH4 as reducing agent. The catalyst was reused in batch conditions over five consecutive runs without any losses of activity or selectivity. Considering the high chemical stability and reusability of the catalytic system, a continuous‐flow protocol was also investigated and defined to minimize the generation of waste and optimize the continuous reuse of the catalyst. Benefits of flow conditions were proven by turnover numbers that increased from 47.5 to 1902 and also by the minimization of both leaching (9.5 vs. 1 ppm) and E‐factor values (8 vs. 23 in batch).

Cardoon (Cynara cardunculus) is a promising crop from which to obtain oilseeds and lignocellulosic biomass. Acid-catalyzed steam explosion is a thermochemical process that can efficiently pre-treat lignocellulosic biomass. The drawback is the production of a high number of carbohydrate degradation products in the liquid fraction that could inhibit microbial growth. In this work, the lignocellulosic biomass of cardoon, gathered from a dedicated field, were used as the raw material for the production of fermentable monosaccharides by employing acid-catalyzed steam explosion. The raw material was pre-soaked with a dilute 1% (w/w) sulfuric acid solution and then subjected to steam explosion under three different severity conditions. The recovered slurry was separated into solid and liquid fractions, which were individually characterized to determine total carbohydrate and inhibitor concentrations. The slurry and the washed solid fraction underwent enzymatic hydrolysis to release glucose and pentose monosaccharides. By conducting the pre-treatment at 175 °C for 35 min and hydrolyzing the obtained slurry, a yield of 33.17 g of monosaccharides/100 g of cardoon was achieved. At the same conditions, 4.39 g of inhibitors/100 g of cardoon were produced.