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Metal–organic frameworks (MOFs) have been observed to exclusively eliminate dyes confined within their respective pores. In this investigation, the synthesis of a breathable MOF structure, MIL-88B(Fe), was pursued with the objective of circumventing restrictions on pore size to enhance its adsorption capabilities. The synthesis of MIL-88B(Fe) was carried out via the assisted solvothermal method at 373 K using inexpensive yet environmentally benign FeCl3·6H2O, 1,4-benzenedicarboxylic acid, and DMF as a metal precursor, linker, and solvent, respectively. Furthermore, the MOF was subjected to extensive analytical characterisation using XRD, FT-IR spectroscopy, N2 gas sorption, TGA, and SEM. The experimental data showed that the utilisation of MIL-88B(Fe) with a dose level of 5 mg for 180 min at a pH of 9 led to the highest levels of adsorption for both dyes, with 162.82 mg g−1 for methylene blue (MB) and 144.65 mg g−1 for rhodamine B (RhB), as a result of the contrast in the molecular size between each dye. The Langmuir and Freundlich models demonstrated a correlation with isotherms, while the thermodynamic analysis demonstrated that MIL-88B(Fe) exhibits distinct endothermic and breathable properties. The efficacy of MIL-88B(Fe) adsorbent for MB and RhB in aqueous solutions indicated exceptional performance, stability, and noteworthy reusability performance.

Conversion of delignified cellulose from rice husk biomass, and model compounds of cellobiose and glucose to levulinic acid (LA) over hierarchical Mn3O4/ZSM-5 catalyst was carried out using a household microwave method, and then compared to the established conventional thermos-reaction method. The hierarchical ZSM-5 was prepared using a double template method, aiming for micro and mesoporous systems developed in the structure. The as-prepared ZSM-5 were modified with Mn3O4 through incipient wetness impregnation with Mn2+ solution followed by calcination at 550 °C. The catalysts were characterized using various techniques such as powder XRD, SEM, BET, AAS, and FT-IR which indicated the hierarchical structure of MFI zeolite (Si/Al of 30–34) with Mn loading of 2.14 wt%. The conversion products were analyzed using HPLC, 1H NMR, and 13C NMR instruments. The microwave-assisted reaction using 600 W for 180 s using delignified cellulose, cellobiose, and glucose gave conversion of 37.27%, 46.35%, and 54.29%, respectively which is close to the conversion given by the conventional reaction carried out at 130 °C for 4 h (36.75%, 55.62%, and 60.9%, respectively). Interestingly, the LA yield from the microwave-assisted reaction (4.33%, 6.12%, and 9.57%) is higher than the yield from the conventional reaction, which only produced 5.2%, 4.88%, and 6.93% respectively. The microwave-assisted method is also shown to give less by-products compared to the thermochemical reaction. Therefore, it could be considered an alternative method for converting cellulose to LA.

Natural zeolite and kaolin are abundant in Indonesia especially in Java and Belitung islands. These materials generally contain high aluminosilicate minerals that can be used as silica and alumina sources for the formation of NaY zeolite. This research aimed to identify the modification of NaY zeolite structure using Bayat natural zeolite as alumina source and Belitung kaolin as silica source and its catalytic activity for n-hexadecane cracking. Pretreatment of materials were performed in several steps: activation, purification, fragmentation for Bayat–Klaten natural zeolite, and silica extraction for Belitung kaolin. The synthesis of NaY was performed hydrothermally using seed-assisted method with crystallization times of 24 and 48 h. The surface area analysis showed a typical surface area of microporous zeolite (i.e., a pore diameter of 1.897 nm) and surface area of 309.4 cm2/g. Meanwhile, powder X-ray diffraction characterization showed that the as-synthesized materials have the structure of NaY zeolite. The optimum crystallization time was 24 h with Si/Al ratio of 4.10. Furthermore, both synthetic and natural sourced NaY zeolites were converted into HY zeolites and employed as cracking catalyst of n-hexadecane in a fixed-bed reactor at 500 °C for 75 s. The natural sourced HY resulted in 59.80% conversion and 59.80% yield of gasoline product (C9–C12). These values were lower than the results given by synthetic HY (80%).