SINTESIS DAN ANALISIS MORFOLOGI DAN LUAS PERMUKAAN KATALIS DARI KULIT PISANG KEPOK SERTA APLIKASINYA SEBAGAI KATALIS PADA TRANSESTERIFIKASI MINYAK KELAPA SAWITNIM.: 22106030019Azzarkasyi AzkaauthorKepok banana peel (Musa acuminata × balbisiana Colla) is a biomass waste containing minerals such as potassium, calcium, phosphorus, and silicon, making it a potential raw material for heterogeneous catalysts. This study aimed to analyze the characteristics of a catalyst derived from calcined kepok banana peel in terms of basicity, morphology, elemental composition, surface area, pore characteristics, and crystal structure, as well as to evaluate its performance in the transesterification of palm oil. The catalyst was prepared by calcination at 750°C for 3 hours and subsequently characterized using Scanning Electron Microscopy-Energy Dispersive X-ray (SEM-EDX), Brunauer-Emmett-Teller (BET), and X-ray Diffraction (XRD) analyses. Basicity was assessed using the Hammett indicator method combined with benzoic acid titration. The fatty acid methyl ester (FAME) product was analyzed in terms of yield and compound composition using Gas Chromatography-Mass Spectrometry (GC-MS). اThe اbasicity ا test ا revealed ا an اH₋ ا value of greater than 9.3, with a total basicity of 0.76 ± 0.043 mmol/g. EDX analysis identified potassium as the predominant metallic element at 15.90%. XRD analysis performed using the Match! application and the Crystallography Open Database (COD) اidentified اthe اcrystalline اphases اCa₃(PO₄)₂, اCaCO₃, اK₄P₂O₇, اK₂SiO₃, اK₂CO₃, ا and KCl. Crystal structure analysis revealed variations in crystal systems, lattice parameters, and interplanar spacings among the constituent phases, while Scherrer equation calculations yielded crystallite sizes ranging from 3.65 to 43.64 nm. BETBJH analysis showed a specific surface area of 20.90 m²/g, a total pore volume of 0.0864 cm³/g, and an average pore diameter of 16.54 nm. Transesterification carried out using 7% catalyst loading, an oil-to-methanol molar ratio of 1:15, a reaction temperature of 60–65°C, and a reaction time of 2 hours produced FAME with a volumetric yield of 75.00%, or approximately 73.92% based on mass estimation. GC-MS analysis showed that 13 out of 16 identified peaks corresponded to FAME compounds, with a total area of 99.48%, in which C18:1 FAME was the most abundant component at 51.84%. These results indicate that the kepok banana peelbased catalyst possesses basic properties along with physical characteristics and a crystal structure that support its use as a heterogeneous catalyst, although the FAME yield obtained has not yet reached the defined target.543 Kimia Analitikal, Kimia Analisis2026-08-28UIN SUNAN KALIJAGA YOGYAKARTA;FAKULTAS SAINS DAN TEKNOLOGIThesis