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A process of chemical activation with phosphoric acid from coconut shell in air to produce activated carbon was developed. The effects of various preparation parameters on the porous texture and surface characteristics were investigated by means of the nitrogen physisorption, Fourier transform‐infrared spectra (FT‐IR), and X‐ray photoelectron spectroscopy (XPS). The adsorption capacities of activated carbon for chromium, lithium, and cesium were also investigated. The surface modification of activated carbon using nitric acid was performed to enhance the adsorption capacities, and the relationship between the adsorption capacities and the surface functional groups was investigated. The oxygen‐containing functional groups on the surface of an activated carbon played a more important role than its textural structure in adsorption of metal ions, especially cesium ion.

Two series of supports, SAPO-11 (Si/Al: 0−0.4) and alumina-coated SBA-15 (Al 2 O 3 : 0−20 wt %), with different pore structures were synthesized. Subsequently, the PtSn bimetallic catalysts supported on these supports were prepared using a coimpregnation method and were characterized by N 2 adsorption measurement, pyridine-adsorbed Fourier transform infrared, CO chemisorption, and H 2 -TPR. The catalytic performances of the catalysts in the hydrotreatment of palm fatty acid distillate (PFAD) were tested using a fixed-bed flow reactor system. PtSn/ALPO-11 (Si/Al: 0) showed the highest n-C 16,18 selectivity (66.4%) among the SAPO-11-based catalysts, and PtSn/20Al/SBA-15 (20% Al 2 O 3 ) showed the highest n-C 16 , n-C 18 selectivity (61.5%) among the SBA-15-based catalysts. It was found that higher Brønsted acid content on the catalyst showed higher isomerization selectivity. Based on the comparison of PtSn/SAPO-11 (0.1) and PtSn/10Al/ SBA-15, the mesoporous structure favored hydrodeoxygenation activity. Also, it was suggested that Brønsted acid affected the structure of active sites and highly dispersed Pt favored formation of n-hexadecane and n-octadecane.

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A novel, eco‐friendly direct graphite exfoliation method was developed using 1‐allyl‐pyridinium‐based ionic liquids (ILs) under microwave irradiation. Exfoliated graphene comprising a few layers was prepared from graphite using 1‐allyl‐pyridinium nitrate under 300 W microwave irradiation for 10 min, which was characterized by X‐ray diffraction, Raman spectroscopy, and X‐ray photoelectron spectroscopy. Density functional theory calculations indicated that the combination of the cations and anions in the ILs led to improved adsorption on the graphite surface. High‐power microwave irradiation can also allow cations to intercalate easily between the graphite layers and increase the efficiency of graphite exfoliation. Solid acid catalysts were prepared from exfoliated graphene via oxidation and sulfonation. The catalytic activity was evaluated for the saccharification of cellulose, where the highest monosaccharide yield of 15.9% was obtained after 24 h at 140°C with a cellulose/solid acid catalyst/water ratio of 0.1/0.05/3 (g/g/g). This performance was superior to that of several commercial catalysts. The magnetic solid acid catalyst which was prepared to facilitate separation from cellulose residue showed constant durability in three activity tests.