Synthesis of Isopulegol Through Cyclisation of Citronellal Using Solid Acid Catalysts: Catalytic Reaction Performance Evaluation and Process Parameters Optimization

The cyclisation of citronellal to isopulegol is a significant intermediate stage in the production of menthols. In this research work, the effects of acid treatment on montmorillonite clay have been investigated and used in citronellal cyclisation reactions. Furthermore, the effects of acid treatment and hetero-poly acid impregnation have been determined on the textural and catalytic properties of montmorillonite clay. The designed catalysts were characterized by XRD, N2 sorption, and NH3- TPD techniques. Acid treatment of montmorillonite resulted in the enhancement of surface area and pore volume. The catalytic activity and selectivity parameters were lessened due to the severe leaching of Al ions from tetrahedral crystalline structures (e.g., weakened structure and loss of acidity). Among all prepared materials, the heteropoly acid supported HCl treated montmorillonite catalyst was observed as a more active, stable, and selective catalyst that showed the highest catalytic performance in citronellal cyclisation under optimized process parameters. The catalytic activity and selectivity were enhanced with rising mesoporosity and acidity parameters due to HCl acid treatment and HPA impregnation.

Direct Conversion of Cellulose Into 5-HMF By Transition-Metal Doped Montmorillonite Catalyst In Water

In this study, transition metal doped montmorillonite catalyts (Cr-MMT, Cu-MMT, Fe-MMT and Zn-MMT) were successfully synthesized by hydrothermal method and evaluated for the conversion of cellulose to 5-HMF in the water media. Metal-MMT catalysts were characterized by XRD, BET, Ammonia-TPD and pyridine-FTIR to investigate the properties of the samples. Using Cr-MMT, an efficient conversion of cellulose to 5-HMF was achieved in the water system, affording a conversion yield 93.47% and 5-HMF yield 9.07% within 6 h at 200oC.

Chromium Pillared Montmorillonite as Catalyst for Liquid Biofuel Conversion

Indonesia has many natural resources, one of which is montmorillonite which very potential to be used as a catalyst in the process converting ethanol to biofuel for an alternative fuel. Montmorillonite has unique properties, because the structure can expand and contract. Research to find alternative energy was needed to replace the limited amount of fossil energy. Chromium metal can be used as catalyst by using montmorillonite as buffer catalyst material. The purpose of this research is to make Cr/montmorillonite catalyst, which was used in the process of converting ethanol to biofuel. Cr/montmorillonite catalyst has synthesised by pillarization method, because it is simple and feasible. The conversion process was carried out by using a fixed bed reactor, peristaltic pump for flow the ethanol with flow rate 1 ml/min, and 1.5g Cr/montmorillonite pellets. The Cr/montmorillonite result was increased the basal spacing in the interlayer montmorillonite amount 150%. TGA shows the results water molecules and hydroxyl compounds decomposition process of Cr/montmorillonite in temperature 631°C. The results of the BET analysis show the specific surface area increased from 30.35 m2/g to 146 m2/g. XRF analysis shows the element content in montmorillonite, that was indicated addition of Cr metals in montmorillonite. FTIR measurements shows that the functional groups in bentonite typical peaks are Mg-OH, Si-O-Si bonds. SEM shows changes in the surface morphology particle in montmorillonite, that is for Cr particles in the form of flake. The GC-MS analysis results show the conversion of ethanol to biofuel or gasoline or biofuel.Â