Metal-organic frameworks (MOFs) have emerged as a new class of supports for metal nanoparticles(NPs) in heterogeneous catalysis because of possible synergetic effects between the two components. In addition, MOFs also can be coated over metal NPs to influence the entire nanoparticle's surface. Herein, NPs were hybridized with UiO-66(Hf) MOF possessing Brønsted acidic sites (on secondary building units) and fabricated Pd@UiO-66 (Hf) core-shell and Pd/UiO-66(Hf) supported catalysts. These hybrid materials exhibited enhanced catalytic properties (TOF increased up to 2.5 times) compared to individual counterparts or their physical mixture for dehydrogenation of ammonia borane(AB) in non-aqueous medium(1,4-dioxane). Further, nanostructure of the hybrid material had pronounced influence on the catalytic properties. The core-shell catalyst exhibited highest activity towards H generation from AB owing to greater contact interface between Pd and MOF. Further, phenylacetylene semi-hydrogenation with AB over Pd@UiO-66 (Hf) furnished styrene selectivity as high as 93.2 % at ∼100 % conversion mostly due to the regulated phenylacetylene diffusion through UiO-66(Hf) shell.

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Here, a novel one‐step process is reported for the production of levulinic acid (LA) from furfural over hierarchical zeolites in a microwave reactor. The furfural conversion and product distribution are determined as a function of formalin concentration (CF) in water, catalyst properties, and heating mode. 20 wt% formalin is found to be the critical concentration, above and below which the 5‐hydroxymethylfurfrual and the LA are formed, respectively. The conversion and LA yield over H‐zeolite are higher by 2.3 and 17 times, respectively, as compared to those over Na‐zeolite. The Brønsted to Lewis acid sites ratio is found to be a crucial catalytic parameter to obtain the best activity and LA yield. Under optimal reaction conditions and with the best catalyst, 42% LA yield is obtained at 90% furfural conversion. The humins formed during the process are characterized using Fourier transformed infrared spectroscopy and thermogravimetric analysis. The humins yield, functionality, and decomposition temperatures are varied with both CF and catalyst properties. The reaction pathways and intermediates are also postulated. The integration of the developed process/route with the existing C6 routes allows the utilization of the entire carbohydrate content of the lignocellulosic biomass to produce LA, and consequently, the overall process becomes more economical.

Ionic Liquid (1‐Butyl‐3‐methylimidazolium Bromide ([BMIM]Br) or Choline Chloride (ChCl)) encapsulated zeolites (HY and H‐MOR) have been synthesized by ship‐in‐a‐bottle strategy and tested for selective conversion of glucose to 5‐Hydroxymethylfurfural (HMF). Nitrogen sorption analysis showed that the surface area and total pore volume decreased and average pore size increased significantly when the zeolites are encapsulated with ionic liquids. The major effect was found to be on the microporosity whereas the mesoporosity is affected only marginally. From Thermogravimetric Analysis it is observed that the decomposition temperature of ionic liquids increased when encapsulated in the zeolite. The catalytic tests were carried out in presence of NaCl and an extraction phase to remove the formed HMF. The test results of BMIMBr−H‐MOR indicate that even though there is a significant decrease in the surface area with encapsulation, the yield and selectivity are higher with this catalyst as compared to its bare zeolite counterpart. The effect of the addition of NaCl and extraction phase and reaction conditions such as reaction time and temperature on activity and yield of HMF are evaluated on the best catalyst. In catalyst stability study, the reasons for deactivation of catalyst are identified by post‐reaction catalyst characterizations.