Ionic liquids (ILs) are promising solvents for the pretreatment of biomass as certain ILs able to completely solubilize lignocellulose. The cellulose can readily be precipitated with an anti-solvent further hydrolysis glucose, but must removed IL recovered and recycled. We describe use aqueous kosmotropic salt solutions form a three-phase system that precipitates biomass, forming IL-rich salt-rich phases. phase behavior [Emim][Ac] phosphate systems is presented, together process recycling...

For understanding solvation by ionic liquids, it is mandatory to characterize their static relative dielectric permittivities ε ("static constants"). Exploiting the definition of in terms zero-frequency limit frequency-dependent dispersion curve, constant an electrically conducting liquid can be extrapolated from relaxation spectra microwave regime. On basis this method, we report constants 42 liquids at 25 °C.

For the temperature range (80 to 120) °C, viscosity data are reported for imidazolium-based ionic liquids 1-octyl-3-methylimidazolium chloride [Omim][Cl], 1-hexyl-3-methylimidazolium [Hmim][Cl], 1-butyl-3-methylimidazolium [Bmim][Cl], 1-ethyl-3-methylimidazolium [Emim][Cl], acetate [Emim][Ac], [Bmim][Ac], and dicyanamide [Bmim] [N(CN)2]. Acetate-based have considerably lower viscosities than corresponding chloride-based ILs. At 25 binary mixtures of [Bmim][Ac] with diluents water,...

In continuation of recent work on the dielectric response imidazolium-based ionic liquids (ILs) (J. Phys. Chem. B, 2006, 110, 12682), we report effect cation variation frequency-dependent permittivity up to 20 GHz liquids. The salts are comprised pyrrolidinium, pyridinium, tetraalkylammonium, and triethylsulfonium cations combined with bis-((trifluoromethyl)sulfonyl)imide anion. spectra resemble those observed for imidazolium same all cases, major contribution results from a diffusive...

We report on a dielectric relaxation study of aqueous solutions ribonuclease A at 298.15 K as function protein concentration between 0.5 and 6 wt % in the MHz/GHz frequency range. The spectra can be decomposed into five modes Debye type diffusive behavior. In agreement with standard interpretation, we assign two dominant low high (β-relaxation γ-relaxation, respectively) to tumbling bulk water relaxation. observe three further (δ1−δ3) β- contrast bimodal δ-dispersion frequently reported....

Different classes of solvents were explored for liquid–liquid extraction (solvent extraction) 2,3-butanediol (BDO) from aqueous solutions. Initially, the activity coefficients (γ∞) BDO in various predicted using thermodynamic models, namely conductor-like-screening model-real (COSMO-RS) and universal functional group coefficient model (UNIFAC-LL). These models validated by comparing distribution (Kd) modeling with experimental data solvents. Lower chain alcohols derivatives phenol showed...

Abstract BACKGROUND Miscanthus×giganteus ( M.×giganteus ) is a potential source for bioethanol or other useful products. Pretreatment of lignocellulosic biomass an essential step prior to enzymatic hydrolysis sugars and fermentation . RESULTS In this work, one‐step process uses aqueous ammonia with without hydrogen peroxide; proposed two‐step in the first peroxide second step. process, overall 89.5% lignin removed. The pretreated followed by using cellulase β‐glucosidase convert cellulose...

A change in solvent can have dramatic effects on the physico-chemical properties of a protein and its stability. In this paper we demonstrate by study solutions enzyme ribonuclease (RNase A) normal water (H2O) deuterated (D2O), to what extend isotopic substitution affects structural dynamic Differential scanning calorimetry (DSC) indicates shift transition temperature from native unfolded state about 62 °C H2O 66 D2O. Pressure perturbation (PPC), relatively new efficient technique, is used...

BACKGROUND Solvent extraction of 2,3-butanediol from dilute fermented systems is a challenging downstream unit operation. Addition certain kosmotropic salts to the aqueous fermentation broth during solvent process can have considerable influence on distribution 2,3-butanediol. This work evaluates usefulness and salting-out effect characteristic in synthetic solutions. RESULTS 10 wt% dipotassium phosphate (K2HPO4) results 1.5–3-fold increase coefficient (Kd) 7–14-fold separation factor (α)...

Aqueous pretreatment using homogeneous acid catalyst is considered as a low-cost technology in the production of lignocellulosic bioethanol. To establish synergism mixed acids, pilot-level aqueous pretreatments bagasse covering wide range combined severity (CS) were carried out. investigate effect application mixture acids on xylose hydrolysis well glucose via and enzymatic hydrolysis, following three combinations explored: (1) oxalic + sulfuric (organic mineral acid), (2) phosphoric...

Pretreatment and enzymatic hydrolysis play a critical role in the economic production of sugars fuels from lignocellulosic biomass. In this study, we evaluated diverse pilot-scale pretreatments different post-pretreatment strategies for fermentable sugarcane bagasse. For pretreatment bagasse at level, steam explosion without catalyst combination sulfuric oxalic acids low high loadings were used. Subsequently, to enhance efficiency pretreated bagasse, three process schemes investigated. first...

Abstract A dielectric relaxation study of aqueous solutions the amphiphilic model peptide N ‐acetyl‐leucine amide (NALA) at 298 K over a wide range hydration levels is presented. The experiments from states where water builds up several layers to single molecules or small clusters are shared by NALA molecules. spectra reveal two modes on 10 and 100 ps timescales. These largely broadened with regard Lorentzian shape caused simple Debye‐type relaxation, well described Kohlrausch–Williams–Watts...

Pretreatment of miscanthus is essential for enzymatic production sugars to yield bioethanol. A two-step process using 10 wt % aqueous ammonia in the first step followed by 1 sodium hydroxide (with or without oxygen hydrogen peroxide) second step. The retains about 90% cellulose and 67% hemicellulose solid while removing 62% lignin. Both steps together achieve 83–90% delignification. Subsequent conversion fermentable close after 96 h. While an oxidant does not significantly increase...

BACKGROUND Pyruvic acid and its salts, key chemicals in the bio-refinery sector, are normally purified liquid form mainly through reactive extractions or chromatographic methods. For isolation of sodium pyruvate, current work explores a repulsive extraction crystallization method using polar aprotic solvents. RESULTS Because high affinity components present fermented broth towards water also due to favorable interaction pyruvate with added solvent, allows from solution. Acetone causes...

Pretreatment of miscanthus is essential for efficient enzymatic production cellulosic ethanol. This study reports a possible pretreatment method using aqueous ethylenediamine (EDA) 30 min at 180 °C with or without ammonia. The mass ratio to EDA was varied from 1:3, 1:1, and 1:0.5, keeping the liquid (EDA + Water) constant 1:8. ammonia-to-miscanthus 1:0.25. After 1:3 EDA, about 75 % lignin removed raw 90 retention cellulose 50 hemicellulose in recovered solid. Enzymatic hydrolysis solid gave...

In the present study we combine dielectric relaxation spectroscopy with generalized Born simulations to explore role of orientational order for protein aggregation in solutions bovine pancreatic insulin at various $p\mathrm{H}$ conditions. Under aggregation-prone conditions low $p\mathrm{H}$, monomers prefer antiparallel dipole alignments, which are consistent orientation monomeric subunits dimer structure. This alignment is also true two dimers, suggesting that already moderate...

Removal of lignin from miscanthus liberates cellulose and hemicellulose for hydrolysis to obtain sugars that can subsequently be fermented ethanol or butanol. Extraction raw at 70°C is feasible when the extracting solvent contains a base (Ethylenediamine, EDA) mixed with an organic mildly hydrophobic ionic liquid. A 50–50 (by weight) mixture EDA ethylene glycol removes 75% weight ratio 10:1. At same miscanthus, 10–90 liquid, 1-ethyl-3-methylimidazolium tosylate ([Emim][Ts]) 60% lignin. These...