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Glycerol carbonate (GC) and glycidol (GD) are commercial products possible from glycerol transformation, which has become a subject of great importance. Among several basic catalysts screened in this work, BaO showed the highest glycerol conversion of 71% with almost complete selectivity to GC. A tandem synthesis of GD with a selectivity as high as 80% with 98% glycerol conversion could be achieved with mixed oxides of Ba and lanthanides (La and Ce) prepared by the coprecipitation method. Although BaO alone showed the highest basicity as measured by CO 2 TPD, tuning of basicity by incorporation of CeO 2 resulted in the formation of GD. Incorporation of Ba into the ceria matrix induced oxygen vacancies in the cerium oxide material. The presence of u″/v″ doublets at 888.7 and 903.2 eV, respectively, in XPS of the Ba−Ce sample also confirmed the oxygen vacancies in the lattice. In this tandem approach to GD, the subsequent decarboxylation of initially formed GC was due to the presence of a CeO 2 lattice with defects, which is known to be the best for CO 2 adsorption. Increase in both catalyst loading and temperature showed a dramatic enhancement in GD selectivity. A plausible reaction pathway for the transesterification of glycerol with DMC to give GC followed by its decarboxylation to GD is also proposed based on the structural characterization and activity studies.

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Etherification of furanic compounds such as furfuryl alcohol (FA) and 5-(Hydroxymethyl) furfural (5-HMF) to the corresponding ethers was successfully achieved over Zr-SBA-15 catalyst. For this purpose, various Zr-SBA-15 catalysts with different Zr/Si molar ratios in self-generated acidic environment were prepared by one-pot strategy in self-generated acidic environment. XRD analysis revealed the increase in the d-spacing from 9.021 nm for parent SBA-15 to 11.66 nm for Zr-SBA-15, confirming the incorporation of Zr into the framework without disturbing the mesoporous structure of SBA-15. For the lowest Zr concentration of 0.09 M, hexagonally ordered porous structure was found to be retained as confirmed by TEM while, increase in Zr/Si molar ratio to 0.14, resulted in loss of long range order mesoporosity. The presence of both Lewis and Brønsted acid sites in Zr-SBA-15 catalyst as evidenced by py-IR, were due to the introduction of Zr in the frame work of SBA-15. The co-existence of Lewis and Brønsted acid sites in Zr-SBA-15 was responsible to catalyze etherification of FA and esterification of levulinic acid producing 2-(Ethoxymethyl) furan and ethyl levulinate selectively, both of which are bio-derived fuel additives.

Efficient and highly selective isomerization of glucose to fructose was achieved by using the inexpensive Ba−Zr mixed metal oxide catalyst. Catalyst was prepared by varying Ba−Zr ratios using co‐precipitation method. Various phases formed, planes exposed, morphology, elemental composition and particle size, basic site density and strength, oxidation state of elements were well studied by using various characterization techniques. The XRD analysis clearly indicates the presence of Ba+2 and Zr+4 in the form of BaO, ZrO2 and BaZrO3 phases. The SEM and HR‐TEM images indicate that, Ba−Zr (2 : 1) catalyst prepared showed uniform morphology with spherical and rod‐shaped particles ranging from 300 to 600 nm. Under the optimized reaction conditions Ba−Zr (2 : 1) catalyst exhibited excellent results in terms of 57 % of glucose conversion with 89 % selective formation of glucose. The presence of both acidic as well as basic sites play vital roles in activating the substrate molecules to selectively yield fructose. Ba−Zr (2 : 1) catalyst showed excellent recyclability performance up to four recycles.

Magnetically separable Ti–Fe3O4@MCM-41 (Ti-MS) catalysts were prepared by postgrafting Ti with varying loading on mesoporous silica containing dispersed magnetite. The hexagonal structure of Ti-MS catalysts with a periodicity in the pores and a highly ordered hexagonal matrix was established by X-ray diffraction and transmission electron microscopy, while diffuse reflectance UV showed the isolated tetrahedral Ti species coordinated with O2–. From the Fourier transform infrared studies, the extent of Ti–O–Si linkage was found to increase with increase in Ti-loading from 1 to 5 wt % beyond which (10%), the intensity of Ti–O–Si band decreased due to the polymerization of the Ti on the silica surface. Silanol groups on the surface of silica interact with the precursor Ti(OiPr)4 to give site isolated tetrahedral Ti-species responsible for complete selectivity to the epoxide in the epoxidation of cyclooctene. The magnetic property facilitated easy recovery of the catalyst for its successful eight recycles showing its stability under reaction conditions.

Effectual waste utilization from plant as well as marine biomass has gained tremendous importance with reference to sustainability. The valorization of marine biomass produces value added compounds containing not only C, H, O but also renewable N atom in the skeleton which widens the scope for its exploration which may prove to be economically bene cial to the society. Heterogeneous catalytic transformation of marine biomass i.e. N-acetyl glucosamine (NAG) to N-substituted aromatic heterocyclic is reported for the very rst time. Cost effective and stable metal oxide catalysts were deployed for the transformation. Catalyst screening study showed that La 2 O 3 was found to be an excellent catalyst for N-acetyl glucosamine (NAG) dehydration which mainly produced 3-acetamidofuran (3AF). The physicochemical properties of the metal oxide catalyst were investigated by various techniques such as XRD, FTIR, MeOH-FTIR, TPD, SEM, N 2 sorption studies and HR-TEM analysis for structure activity relationship. The effect of various reaction parameters such as catalyst concentration, reaction temperature, reaction time and solvent effect on dehydration of N-acetyl glucosamine has been studied in detail for higher yields. The results revealed that the presence of weak basic sites which are Brønsted in nature and nano pores present on the surface were responsible for improved dehydration of the chitin biomass to selectively yield 3-acetamidofuran (3AF). La 2 O 3 catalyst showed optimum 50% 3AF yield from N-Acetyl glucosamine at 180 ºC in 3h. E cacious exploitation of marine biomass to value added chemicals using heterogeneous catalyst through simple route and easy separation of N-substituted heterocyclic aromatics is the most innovative aspect of the current study. Thus, utilization of heterogeneous catalyst and renewable biomass as a raw material indicates a transition towards more sustainable and greener approach. Statement Of NoveltyAs marine biomass is abundantly available on valorization widens its scope for production of value added products and platform chemicals. As far as sustainability and green synthesis is concerned we report for the rst time dehydration of NAG to renewable N-containing furan derivatives by heterogeneous catalyst without use of any additives, ionic liquids or boron compounds. The catalyst showed high stability, easy separation and excellent recyclability upto 5 cycles. The co-operative effect of Brønsted basicity and nanopores on the catalyst play vital role in (100 %) NAG conversion to yield 50 % 3AF and 20 % 3A5AF. 3AF and 3A5AF may nd application as precursors for the synthesis of naturally occurring antibiotic and antitumor drug proximycin A, B and C, amino sugars, pyridine derivatives etc.

Hierarchical TS-1 materials were synthesized using hydrothermal synthesis and post modification technique through desilication. They were evaluated for hydroxylation of anisole to produce industrially important chemicals, o-methoxyphenol (OMP) and p-methoxyphenol...