Search results for "butanol"

Measurements and correlation at different temperatures of liquid–liquid equilibria of 2-butanol or 2-methyl-2-butanol+1,2,3-propanetriol+water ternar…

2014

Abstract In this work, the experimental liquid–liquid equilibria (LLE) data of 2-methyl-2-butanol + 1,2,3-propanetriol (glycerol) + water and 2-butanol + 1,2,3-propanetriol (glycerol) + water systems at different temperatures are presented. The LLE of the systems has been measured between 283 and 323 K. The NRTL and UNIQUAC models were applied to the ternary systems. The interaction parameters obtained from both models successfully correlated the equilibrium compositions. The experimental tie lines were compared to the values predicted by the UNIFAC method. Finally, the solvent capability of both alcohols was checked in order to separate the mixture formed by glycerol and water.

Estudio del proceso simultáneo de sacarificación y fermentación aceto-butílica-etílica a partir de paja de arroz

2022

El sistema energético de la Unión Europea está experimentando una profunda transformación con la finalidad de mitigar el cambio climático y de asegurar la independencia energética de sus Estados Miembro. Para ello se están llevando a cabo una serie de medidas como la implantación de una cuota mínima en el transporte del 3.5% de biocarburantes producidos a partir de residuos lignocelulósicos, entre otros biocombustibles, para 2030. En este contexto, toma relevancia la producción de biobutanol a partir de residuos lignocelulósicos mediante la fermentación aceto-butílica-etílica (ABE). Sin embargo, su implantación a nivel industrial continúa presentando una serie de desafíos entre los que se p…

Bacterial Bioconversion of Primary Aliphatic and Aromatic Alcohols into Acids: Effects of Molecular Structure and Physico-chemical Conditions

1997

The biotransformation of four alcohol substrates (butanol, 2-methylbutanol, 3-methylbutanol and 2-phenylethanol) into their acids was studied using a strain of Acetobacter aceti. Bioconversion yields depended on the molecular structure of the alcohol. Biotransformation of high concentrations of alcohols was possible until the precursor reached an inhibiting concentration (3.8 g dm -3 for butanol and 3-methylbutanol, 4.2 g dm -3 for 2-methylbutanol). In contrast, biotransformation of 2-phenylethanol decreased when alcohol concentration was higher than 0.3 g dm -3 . Dissolved oxygen concentrations and pH conditions of the medium were important factors in improving bioconversion. Transformatio…

Optimization of alkali pretreatment to enhance rice straw conversion to butanol

2021

Abstract The use of rice straw (RS) was enhanced to produce biobutanol as biofuel, for which the NaOH pretreatment was optimized by considering the butanol-biomass ratio that quantify the mass balance efficiency of the three sequential stages of the process: pretreatment, enzymatic hydrolysis and fermentation by Clostridium beijerinckii. The optimum point (solid loading of 5% w/v with 0.75% w/v NaOH at 134 °C for 20 min) of the best cost-wise option yielded an enhanced biomass use of 77.6 g kg RS−1. A maximum butanol titer of 10.1 g L−1 was reached after 72 h of fermentation with the complete uptake of glucose and nearly complete uptake of xylose. The NaOH concentration was the most influen…

Photocatalytic oxidation of aromatic alcohols to aldehydes in aqueous suspension of home-prepared titanium dioxide

2008

Abstract Oxygenated aqueous suspensions of home-prepared (HP) and commercial TiO2 catalysts were used in a batch photoreactor for carrying out the oxidation of benzyl alcohol (BA) and 4-methoxybenzyl alcohol (MBA) under different operative conditions. HP catalysts were synthesized from TiCl4 and underwent a hydrolysis treatment of different times under mild conditions. The textural characterization of catalysts was carried out with XRD, SEM observations, BET surface area and porosity measurements. For both alcohols the main oxidation products were the corresponding aromatic aldehydes and CO2. The HP catalysts exhibited selectivity values towards the aldehyde production up to 28% (BA convers…

Thermodynamics of binary mixtures: Volumes, heat capacities, and dilution enthalpies for then-pentanol+2-methyl-2-butanol system

1983

The densities, heat capacities, and dilution enthalpies ofn-pentanol+2-methyl-2-butanol mixtures have been measured, in many cases as a function of temperature, over the complete mole fraction range. Excesses thermodynamic properties, apparent and partial molar heat capacities, volumes and expansibilities were derived. The concentration and temperature dependences of these functions are discussed in terms of the variations of the structure of the system caused by the participation of the two alcohol molecules (with quite different steric hindrance of the alkyl chain around the-OH group) in the dynamic intermolecular association process through hydrogen bonding.

Heat capacities of butanol and pentanol in aqueous dodecyltrimethylammonium bromide solutions

1987

Heat capacities of the ternary systems water-dodecyltrimethylammonium bromide (DTAB)-butanol and water-DTAB-pentanol were measured at 25°C. The standard partial molar heat capacities of pentanol in micellar solutions show a maximum at about 0.35 mol-kg−1 DTAB that has been attributed to a micellar structural transition. This maximum tends to vanish by increasing the alcohol concentration and by decreasing the alcohol alkyl chain length; in the case of butanol it was not detected. The behavior of the standard partial molar heat capacities of alcohols in micellar solutions in the region above the cmc and below the structural transition was explained using a previously reported mass-action mod…

Vapor−Liquid Equilibrium of Binary Mixtures of Tetrachloroethylene with 1-Pentanol, 3-Methyl-1-butanol, and 2-Methyl-1-butanol

1999

Isobaric vapor−liquid equilibria have been obtained for the systems tetrachloroethylene + 1-pentanol, tetrachloroethylene + 3-methyl-1-butanol, and tetrachloroethylene + 2-methyl-1-butanol, using a...

Hiilihydraateista bioteknisesti valmistettavat merkittävät teollisuuskemikaalit

2010

Ethanol inhibits astroglial cell proliferation by disruption of phospholipase D-mediated signaling.

2002

The activation of phospholipase D (PLD) is a common response to mitogenic stimuli in various cell types. As PLD-mediated signaling is known to be disrupted in the presence of ethanol, we tested whether PLD is involved in the ethanol-induced inhibition of cell proliferation in rat cortical primary astrocytes. Readdition of fetal calf serum (FCS) to serum-deprived astroglial cultures caused a rapid, threefold increase of PLD activity and a strong mitogenic response; both effects were dependent on tyrosine kinases but not on protein kinase C. Ethanol (0.1-2%) suppressed the FCS-induced, PLD-mediated formation of phosphatidic acid (PA) as well as astroglial cell proliferation in a concentration…