Heterogeneous acidic Zr-MOF(metal-organic framework)catalyst,UiO-66/SO_(3)H was synthesized for palm fatty acid distillate(PFAD)-methanol esterification.The characterizations for catalyst precursor and active catalyst...Heterogeneous acidic Zr-MOF(metal-organic framework)catalyst,UiO-66/SO_(3)H was synthesized for palm fatty acid distillate(PFAD)-methanol esterification.The characterizations for catalyst precursor and active catalyst were carried out using infrared spectroscopy,ammonia-temperature desorption analysis,thermogravimetric analyser,X-ray diffraction,surface textural analyser,and field emission scanning microscopy.The surface area of UiO-66 and UiO-66/SO_(3)H was 714.77 m^(2)/g and 503.02 m^(2)/g,respectively.Meanwhile,the acidity strength shown an increase in values,rising from 3.14 mmol/g to 7.98 mmol/g.Throughout the catalytic screening test under fixed parameters,UiO-66/SO_(3)H produced 72.3%of fatty acid methyl ester(FAME)while 45.9%catalyzed by UiO-66.Then,UiO-66/SO_(3)H was selected for response surface methodology-central composite design(RSMCCD)optimization.Following 31 experiments,the optimized conditions were determined to be 75℃,1.3 h,4.2 wt%catalyst,and a methanol to PFAD molar ratio of 21:1,resulting in a yield of 98.6%FAME.Reusability tests demonstrated that the catalyst maintained its activity for seven cycles,averaging 72.4%yield but subsequently dropping to 53.8%after the eighth cycle.Environmental sustainability was evaluated using life-cycle assessment(LCA)across seven impact categories:global warming potential,stratospheric ozone depletion,acidification potential,terrestrial ecotoxicity,freshwater ecotoxicity,marine ecotoxicity,and fossil resource scarcity.LCA analysis revealed that the PFAD process had a substantial global warming impact,with the exception of microalgae-based biodiesel.The PFAD process has lower acidification potential than soybean or lignocellulosic biomass.Our advanced biodiesel production method,with minimal methanol and low electricity,is an environmentally friendly alternative.展开更多
基金financial support under Insiatif Putra Siswazah from Universiti Putra Malaysia(Kod Project:9774800)Authors extend their thanks to Researchers Supporting Project(RSP2025R160)+1 种基金King Saud University(Riyadh,Saudi Arabia)funded in part by the U.S.Department of Agriculture,Agricultural Research Service.
文摘Heterogeneous acidic Zr-MOF(metal-organic framework)catalyst,UiO-66/SO_(3)H was synthesized for palm fatty acid distillate(PFAD)-methanol esterification.The characterizations for catalyst precursor and active catalyst were carried out using infrared spectroscopy,ammonia-temperature desorption analysis,thermogravimetric analyser,X-ray diffraction,surface textural analyser,and field emission scanning microscopy.The surface area of UiO-66 and UiO-66/SO_(3)H was 714.77 m^(2)/g and 503.02 m^(2)/g,respectively.Meanwhile,the acidity strength shown an increase in values,rising from 3.14 mmol/g to 7.98 mmol/g.Throughout the catalytic screening test under fixed parameters,UiO-66/SO_(3)H produced 72.3%of fatty acid methyl ester(FAME)while 45.9%catalyzed by UiO-66.Then,UiO-66/SO_(3)H was selected for response surface methodology-central composite design(RSMCCD)optimization.Following 31 experiments,the optimized conditions were determined to be 75℃,1.3 h,4.2 wt%catalyst,and a methanol to PFAD molar ratio of 21:1,resulting in a yield of 98.6%FAME.Reusability tests demonstrated that the catalyst maintained its activity for seven cycles,averaging 72.4%yield but subsequently dropping to 53.8%after the eighth cycle.Environmental sustainability was evaluated using life-cycle assessment(LCA)across seven impact categories:global warming potential,stratospheric ozone depletion,acidification potential,terrestrial ecotoxicity,freshwater ecotoxicity,marine ecotoxicity,and fossil resource scarcity.LCA analysis revealed that the PFAD process had a substantial global warming impact,with the exception of microalgae-based biodiesel.The PFAD process has lower acidification potential than soybean or lignocellulosic biomass.Our advanced biodiesel production method,with minimal methanol and low electricity,is an environmentally friendly alternative.
