STUDI PENDAHULUAN KONVERSI TRIGLISERIDA RBDPO MENJADI ALKANA CAIR SEBAGAI BAHAN BAKAR ALTERNATIF MELALUI PROSES HIDROGENASI KATALITIK

Menipisnya sumber bahan bakar fosil semakin mendorong penelitian tentang bahan bakar alternatif. Pada penelitian ini, dilakukan studi pendahuluan tentang hidrogenasi katalitik yang merupakan salah satu metode untuk mengkonversi minyak nabati menjadi bahan bakar. Katalis NiO/Al2O3 yang kemudian direduksi menjadi Ni/Al2O3 memiliki aktifitas untuk menghidrogenasi trigliserida pada RBDPO menjadi beberapa produk diantaranya alkana cair, yang dilakukan di dalam suatu reaktor batch dengan desain tertentu pada tekanan 7,5 kg/cm2 dan suhu 300oC. Katalis-katalis lain yang telah berhasil disintesis dengan metode wet impregnation namun belum diuji aktifitasnya pada penelitian ini diantaranya adalah MoO/Al2O3 dan NiOMoO/Al2O3 yang kemudian masing-masing direduksi menjadi Mo/Al2O3 dan NiMo/Al2O3. Karakteristik katalis berupa kandungan prekursor logam pada material pendukung Al2O3 untuk masing-masing katalis juga dianalisis pada penelitian ini. Berbagai jenis reaktor yang dirancang, diantaranya adalah reaktor tipe A, tipe B, tipe C, tipe D, dan tipe E. Uji coba reaktor dilakukan untuk mengetahui kapasitas pemanasan dari mantel heater, daya tahan alat terhadap parameter suhu, reaksi kimia, dan tekanan, serta untuk mengetahui perubahan tekanan yang diakibatkan oleh perubahan suhu. Analisa GCMS pada produk yang dihasilkan dari penelitian ini menunjukkan produk alkana cair yang memiliki rentang rantai karbon C10-C17 sebanyak 0,6% sampai 2,5%

Selective Electrocatalytic Oxidation of Biomass‐Derived 5‐Hydroxymethylfurfural to 2, 5‐Diformylfuran: from Mechanistic Investigations to Catalyst Recovery

The catalytic transformation of bio-derived compounds, specifi-cally 5-hydroxymethylfurfural (HMF), into value-added chemi-cals may provide sustainable alternatives to crude oil andnatu-ral gas-based products. HMF can be obtained from fructoseand successfully converted to 2,5-diformylfuran (DFF) by an en-vironmentally friendlyorganic electrosynthesis performed in anElectraSyn reactor, using cost-effective and sustainable graph-ite (anode) and stainless-steel (cathode) electrodes in an undi-vided cell, eliminating the need for conventionalpreciousmetal electrodes. In this work, the electrocatalysis of HMF isperformed by using green solvents such as acetonitrile, g-vale-rolactone, as well as PolarClean, which is used in electrocataly-sis for the first time. The reaction parameters and the synergis-tic effects of the TEMPOcatalyst and2,6-lutidine base are ex-plored both experimentally and through computationmodel-ing. The molecular design and synthesis of asize-enlarged C3-symmetric tris-TEMPO catalystare also performed to facilitate asustainable reactionwork-up through nanofiltration. The ob-tained performanceisthen compared with those obtained byheterogeneous TEMPO alternatives recov ered by using an ex-ternal magnetic field and microf iltration. Resultsshow that thisnew methodofelectrocatalytic oxidation of HMF to DFF canbe achieved with excellent selectivity,good yield, and excellent catalyst recovery

Emergent collective motion of self-propelled condensate droplets

Recently, there is much interest in droplet condensation on soft or liquid/liquid-like substrates. Droplets can deform soft and liquid interfaces resulting in a wealth of phenomena not observed on hard, solid surfaces (e.g., increased nucleation, inter-droplet attraction). Here, we describe a unique complex collective motion of condensate water droplets that emerges spontaneously when a solid substrate is covered with a thin oil film. Droplets move first in a serpentine, self-avoiding fashion before transitioning to circular motions. We show that this self-propulsion (with speeds in the 0.1-1 mm/s range) is fuelled by the interfacial energy release upon merging with newly condensed but much smaller droplets. The resultant collective motion spans multiple length scales from submillimetre to several centimetres, with potentially important heat-transfer and water-harvesting applications

Interaction entre la texture, la structure et la réactivité dans des matériaux poreux de type MOFs

Metal-Organic Frameworks (MOFs) sont constitués de clusters métalliques connectés dans les ligands organiques. L'objectif principal de ma thèse était de caractériser la texture, la structure et la réactivité des MOFs dans le cas de systèmes présentant des défauts, amorphes et composites.La première étude est centrée sur les propriétés de la famille Fe-BTC et ce travail a été réalisé en collaboration avec l'Université d'Utrecht et l'Université d'Oxford. Une étude comparative entre le MIL-100(Fe) et son homologue commercial Basolite F300 (BASF) qui est amorphe ont été évaluées par l’adsorption de méthanol et d'autres techniques de caractérisation. De plus, les deux matériaux ont été testés pour être utilisés comme support pour l'imprégnation des métaux.Dans la deuxième étude, le broyage à la bille est utilisé comme stratégie de modification post-synthèse de MOFs. Le matériau ZIF-8 a été sélectionné de cas car il s'agit d'un MOF disponible dans le commerce (Basolite Z1200) et qui est en train de devenir de référence dans ce domaine. Ce chapitre examiner des propriétés flexibles, de la texture, de la structure, et la réactivité.Les MOFs UiO-66 et MOF-808 sont également analysées. Ces études ont été réalisées en collaboration avec l'Université Technique de Munich. UiO-66 contenant différents défauts d'ingénierie sont examinées. Nous avons démontré que les mesures d’adsorption de vapeur peuvent être un outil précieux pour accéder à la chimie des défauts. Le deuxième système est la série MOF-808 qu’une étude complète est présentée allant des diverses stratégies de synthèse de MOFs défectueux et composites jusqu'à leur propriété d'adsorption et de réactivitéMetal-organic frameworks (MOFs) are a class of porous materials that constructed from metal clusters connected with organic linkers. The main objective of my PhD was to characterize the texture, structure, and reactivity of MOFs materials with a particular focus on defective, amorphous and composite materials. The first study is centered on the properties of the Fe-BTC family and this work was realized in collaboration with Utrecht University and the University of Oxford. A comparative study between crystalline MIL-100(Fe) and its commercial counterpart amorphous Basolite F300 (BASF) were studied by using methanol adsorption to predict the reactivity. Other characterization methods are introduced to investigate both materials which were further tested to be used as supports for metal-impregnation. In the next study, ball-milling was employed as a post-synthesis strategy for MOF modification. This ZIF-8 material was selected since it is commercially available (Basolite Z1200) and is becoming one of the reference materials in this area. Extensive studies including flexibility, textural, structural, as well as reactivity of different milling products is presented. Zirconium-based MOFs (UiO-66 and MOF-808) were also examined in this thesis. These studies were performed in collaboration with TU Munich. UiO-66 series containing engineered defects are first examined. We demonstrated that vapor adsorption measurement is a valuable tool to access the chemistry of the defects. The second studied system is MOF-808 series, where a comprehensive study is presented starting from synthesis strategies of defective and composite MOFs up to adsorption properties and reactivity

Tuning the properties of MOF‐808 via defect engineering and metal nanoparticle encapsulation

Defect engineering and metal encapsulation are considered as valuable approaches to fine‐tune the reactivity of metal–organic frameworks. In this work, various MOF‐808 (Zr) samples are synthesized and characterized with the final aim to understand how defects and/or platinum nanoparticle encapsulation act on the intrinsic and reactive properties of these MOFs. The reactivity of the pristine, defective and Pt encapsulated MOF‐808 is quantified with water adsorption and CO(2) adsorption calorimetry. The results reveal strong competitive effects between crystal morphology and missing linker defects which in turn affect the crystal morphology, porosity, stability, and reactivity. In spite of leading to a loss in porosity, the introduction of defects (missing linkers or Pt nanoparticles) is beneficial to the stability of the MOF‐808 towards water and could also be advantageously used to tune adsorption properties of this MOF family

Chemically recyclable nanofiltration membranes fabricated from two circular polymer classes of the same monomer origin

Nanofiltration is widely used in various industries to separate solutes from solvents. To foster a circular economy, establishing a closed-loop lifecycle for the membrane materials is highly important. In this study, we fabricated recyclable nanofiltration membranes from chemically recyclable polymers —polyester P(BiL=)ROP and poly(cyclic olefin) P(BiL=)ROMP— using γ-butyrolactone as a green solvent. These two polymers, of two different polymer classes, were obtained from a single monomer, which could be recycled back to the same monomer, exhibiting the unique “one monomer–two polymers–one monomer” closed-loop chemical circularity. The effect of physical treatment, such as annealing, hot-pressing, and air exposure on the morphological characteristics and performance of the nanofiltration membranes was investigated. We revealed the interplay between membrane pore size, thickness, density and the molecular sieving performance of the nanofiltration membranes. Solute rejections were mainly governed by the membrane pore size. However, solvent flux was mainly governed by the membrane density that determines the free volume interconnectivity. The membranes exhibited a tunable molecular weight cutoff between 553 and 777 g mol−1 and methanol permeance between 5.9 and 9.8 L m–2 h–1 bar−1. The membranes exhibited excellent long-term nanofiltration stability over 1 week. The combination of the green solvent used for membrane fabrication and the circular life cycle of the polymer membrane brings one step closer to closing the circularity loop of membrane technology

Using water adsorption measurements to access the chemistry of defects in the metal–organic framework UiO-66

International audienc

Metal-organic frameworks as catalyst supports : influence of defects on metal nanoparticle formation

International audienc