以UiO-66擔載K-ZrO2觸媒進行棕櫚酸甲酯之甘油解反應

Abstract

本研究探討了基於金屬有機骨架 (MOF) UiO-66 的介孔 K-ZrO2 催化劑的合成、表徵及其催化棕櫚酸甲酯和甘油的甘油解反應性能。K-ZrO2 催化劑採用浸漬法製備，其中 UiO-66 負載不同量（60、120 和 180 毫克）的硝酸鉀 (KNO3)，然後進行兩步鍛燒。首先在氮氣保護下分別在 550°C、650°C 和 750°C 的溫度下鍛燒，然後在空氣中加熱至 400°C。對所得催化劑進行 X 射線衍射 (XRD)、傅立葉轉換紅外光譜 (FTIR)、熱重分析 (TGA)、Brunauer-Emmette-Teller (BET) 物理吸附 N2 以及掃描電子顯微鏡和能量色散 X 射線光譜儀 (SEM-EDS) 技術表徵，以分析其結晶度、熱穩定性、表面積、形態和元素組成。在間歇反應器中評估催化性能，條件為：溫度為 220°C，甘油與棕櫚酸甲酯的莫耳比為 1:1，催化劑重量百分比為催化劑重量佔棕櫚酸甲酯重量的 1%，反應時間為 7 小時。結果表明，K-ZrO2 催化劑的性能優於空白 UiO-66。介孔 K-ZrO2-120-650 催化劑具有最高的鹼度（1.80 mmol/g 來自弱鹼性位點，0.25 mmol/g 來自強鹼性位點）和 BET 表面積（78.85 m2/g），單甘油酯產率最高，為 21.98%，雙甘油酯產率最高，為 29.13%，棕櫚酸甲酯轉化率最高，為 99.08%。研究結果表明，UiO-66 衍生的 K-ZrO2 可以從生物柴油副產品中持續生產增值甘油酯。

This study explores the synthesis, characterization, and catalytic performance of mesoporous K-ZrO2 catalysts derived from the metal-organic framework (MOF) UiO-66 for glycerolysis of methyl palmitate and glycerol. The K-ZrO2 catalyst prepared with impregnation method, where UiO-66 was loaded with different amounts (60, 120 and 180 mg) of potassium nitrate (KNO3) followed by a two-step calcination. First under nitrogen at different temperatures 550°C, 650°C and 750°C and subsequent heating in air 400°C. The resulting catalysts were characterized by X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TGA), Physisorption of N2 was performed from Brunauer-Emmette-Teller (BET) and Scanning Electron Microscope and energy dispersive X-ray spectrometer (SEM-EDS) techniques to analyze its crystallinity, thermal stability, surface area, and morphology and elemental composition. Catalytic performance was evaluated in a batch reactor under conditions Temperature at 220 °C, 1:1 molar ratio between glycerol and methyl palmitate, catalyst 1 percent weight compared weight catalyst to weight methyl palmitate, reaction time 7 hours. Results showed that K-ZrO2 catalysts outperformed compared to the blank UiO-66. the mesoporous K-ZrO2-120-650 catalyst has the highest basicity (1.80 mmol/g form weak sites and 0.25 mmol/g form strong sites) and BET surface area (78.85m2/g) achieving the highest monoglyceride yield at 21.98%, diglyceride yield at 29.13% and conversion of methyl palmitate at 99.08 %. The findings suggest that UiO-66 derived K-ZrO2 is sustainable production of value-added glycerides from biodiesel byproducts.