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Farnesene-Derived Polyolefin Base Oils
Published in Leslie R. Rudnick, Synthetics, Mineral Oils, and Bio-Based Lubricants, 2020
Jeff Brown, Hyeok Hahn, Lynn Rice, Paula Vettel, Jason Wells
Finally, the fully hydrogenated crude base oil is fractionated into several viscosity grades of base oil having a narrow boiling point distribution [34]. The monomers and dimers are separated using a vacuum distillation column, and the heavier oligomers (average expected boiling point [AEBP] up to 525°C) are recovered using short-path distillation. The process steps and plant for producing farnesene-derived base oils (FDBOs) are shown schematically in Figure 26.6 [34].
Recovery of bioactive compounds in citrus wastewater by membrane operations
Published in Alberto Figoli, Jan Hoinkis, Sacide Alsoy Altinkaya, Jochen Bundschuh, Application of Nanotechnology in Membranes for Water Treatment, 2017
Alfredo Cassano, Carmela Conidi, René Ruby-Figueroa
Essentially pesticide-free citrus oil can be obtained by mild distillation of raw citrus oil in one or more short-path distillation columns, from which the essentially pesticide-free citrus oil is collected as the distillant; all the pesticides from the feed material are collected in the residue stream from the last column in the series (Muraldihara, 1996).
Farnesene-Derived Base Oils
Published in Brajendra K. Sharma, Girma Biresaw, Environmentally Friendly and Biobased Lubricants, 2016
Jeff Brown, Hyeok Hahn, Paula Vettel, Jason Wells
Finally, the fully hydrogenated crude base oil is fractionated into several viscosity grades of base oil having a narrow boiling point distribution [39]. The monomers and dimers are separated using a vacuum distillation column; and the higher oligomers (average expected boiling point: up to 525°C) are recovered using short-path distillation. The process steps and plant for producing FDBOs is schematically shown in Figure 1.6 [39].
Optimisation of Microwave-Assisted Extraction of Squalene from Amaranthus spp. Seeds
Published in Journal of Microwave Power and Electromagnetic Energy, 2019
María A. Lozano-Grande, Gloria Dávila-Ortiz, Jorge García-Dávila, Gabriel Ríos-Cortés, Eduardo Espitia-Rangel, Alma L. Martínez-Ayala
Comparing both systems, the MAE method was more than double of Soxhlet extraction but similar to the literature. He et al. (2002) and Popa et al. (2015) describe a squalene yield of 370-8100 mg·100g−1oil with conventional extraction, while Wejnerowska et al. (2013) and Babeanu et al. (2016) reported for Amaranthus 9-49% of squalene in the extract using SFE with CO2 during 80-130 min of time extraction and 130 °C, or by short path distillation with 15.1% of squalene at 180 °C. Under these circumstances, the use of MAE may offer advantages over traditional methods principally if it is desired to obtain a specific compound. Moreover, it is important to note that the real extraction time of MAE was reduced to 25 min, which is an additional advantage to save energy consumption.
On the balance between nematic and smectic phases in 2′,3′-difluoro-4,4″-dialkyl-p-terphenyls
Published in Liquid Crystals, 2019
Agata Wąchała, Marta Pytlarczyk, Przemysław Kula
2,3-difluoro-4-iodo-4ʹ-hexylbiphenyl: 2,3-difluoro-4ʹhexylbiphenyl (120 g; 0.44 mol) and 300 ml of dry tetrahydrofurane (THF) were placed in four-neck 2L reaction flask (mechanical stirring, 2x dropping funnels, nitrogen inlet) which was flushed with dry nitrogen. Mixture was cooled to −70°C on dry-ice acetone bath, and the hexane solution of n-BuLi (200 ml; 2.5 mol/L; 0.49 mol) was dropped with a speed to not exceed −65°C, during the alkyllithium reagent addition proper mechanical stirring was assured. After the addition of n-BuLi, the reaction mixture was stirred for 2 h then THF solution of iodine (125 g, 0.49 mol in 200 ml of THF) was added dropwise, maintaining temperature below −60°C. After the iodine addition, cooling bath was removed and the reaction mixture slowly reached to RT. The excess of unreacted iodine was reduced using Na2SO3 solution. Then THF was removed using rotary evaporator and 10% HCl was added to neutralise the mixture. Product was extracted three times to a mixture of hexane–cyclohexane–toluene (300 + 150 + 50 ml), and washed three times with water. The organic layer was separated, dried over MgSO4 and solvent removed on the rotary evaporator. Crude product, containing usually few percent of unreacted starting compound, was used without further purification. If higher purity is necessary short path distillation can be applied. Authors have found that impurities arising in this step are separated during first crystallisation of the final products purification and do not deteriorate the yield of the final cross-coupling. Yield 217 g (94%). MS(EI) m/z:224(M+•); 329; 201.
The future of isosorbide as a fundamental constituent for polycarbonates and polyurethanes
Published in Green Chemistry Letters and Reviews, 2021
Olga Gómez-de-Miranda-Jiménez-de-Aberasturi, Ander Centeno-Pedrazo, Soraya Prieto Fernández, Raquel Rodriguez Alonso, Sandra Medel, Jose María Cuevas, Luciano G. Monsegue, Stefaan De Wildeman, Elena Benedetti, Daniela Klein, Hartmut Henneken, José R. Ochoa-Gómez
Ochoa-Gómez et al. (10) optimized the IBMC synthesis using alkaline carbonates and DMC in excess of 30:1 with respect to isosorbide; enough to maintain the oligomer production between 5% and 10%. In both processes, IBMC purities up to 99% can be obtained with the use of different purification techniques as short path distillation (19), or organic solvent nanofiltration membranes (21).