B. KreatananchaiE. SomsookT. KiatsiriroatK. PunyawudhoMahidol UniversityChiang Mai University2022-08-042022-08-042021-08-01Applied Nanoscience (Switzerland). Vol.11, No.8 (2021), 2371-238121905517219055092-s2.0-85111303353https://repository.li.mahidol.ac.th/handle/20.500.14594/76089The strong electrostatic adsorption (SEA) technique was used to prepare palladium catalysts on a graphene support to convert stearic acid to diesel-like hydrocarbon via a deoxygenation process. The pH shifts of graphene were determined, and the point of zero charge (PZC) was obtained at pH = 4.6. With a moderately low PZC, the cation Pd precursor (i.e., [Pd(NH3)4]2+—palladium tetraammine—PdTA) was preferred. In the adsorbed conditions, PdTA and the graphene surface attained the strongest electrostatic adsorption at pH = 12 and had the maximum metal surface density around 0.6 μmol/m2. The Pd loading of 5 wt% catalysts was controlled by the initial concentration of PdTA. The Pd particle size distribution was considerably uniform and had a diameter around 2–3 nm according to transmission electron microscopy (TEM). The ring pattern from electron diffraction (ED) and the spectra from X-ray diffraction (XRD) verified that the Pd metal had a face-centered cubic (fcc) crystal structure. The deoxygenation reaction was carried out and reached 99% conversion of stearic acid using 5 wt% Pd/graphene catalysts with mass of 0.6 g. The main product was straight chain hydrocarbon called heptadecane (C17H36), suggesting a decarboxylation pathway. Moreover, the diesel-like hydrocarbon (C16–C21) attained a maximum selectivity at 85.4%.Mahidol UniversityBiochemistry, Genetics and Molecular BiologyChemistryEngineeringMaterials SciencePhysics and AstronomyArticleSCOPUS10.1007/s13204-021-02009-w