Acetic Acid In Aqueous Phase Research Articles

Extraction of Lanthanide Nitrates in Multicomponent Aqueous-Organic Two-Phase Systems with D2EHPA

Lanthanum nitrate distribution in three-component aqueous-organic systems with D2EHPA from acetate or acetic acid–acetate solutions has been studied, it has been shown that variation in sodium acetate concentration or composition of CH3COONa–CH3COOH mixture can affect metal distribution ratios. It has been found that extraction in three-component mixture of 1: 1: 1 composition (aqueous solution Ln(NO3)3 + CH3COONa + CH3COOH–D2EHPA in hexane–isopropyl alcohol) can provide lanthanide separation, which is dependent on the ratio of sodium acetate and acetic acid in aqueous phase and on D2EHPA concentration in organic phase. Lanthanide–lanthanum separation factors have been calculated for the extraction of lanthanide nitrates from acetic acid–acetate solutions.

Valorization of a natural residue (sawdust) as adsorbent to remove the acetic acid in aqueous solutions

The objective of this work seeks a double environmental aspect. On the one hand, a valorization of a natural residue (sawdust) as adsorbent; and, on the other hand, the study of its ability to remove the acetic acid in aqueous phase. The raw sawdust was prepared by alkaline treatment and calcination at 250°C. The physicochemical characterization was carried out by thermogravimetry, Fourier transform infrared spectroscopy and analysis of the specific surface area by BET method. The effect of the initial concentration, contact time, stirring speed, adsorbent mass, solution temperature and ionic strength was studied in batch mode. The adsorption kinetics of acetic acid follows a pattern of pseudo-second-order with the contribution of the intraparticle diffusion. The results of the adsorption equilibrium were analyzed by three models (Langmuir, Freundlich and Temkin). The results are of interest and encourage us to test other potential chemical pollutants of water.

Incident light dependence for photocatalytic degradation of acetaldehyde and acetic acid on S-doped and N-doped TiO 2 photocatalysts

We have synthesized S (S 4+)-doped and N (N 3−)-doped TiO 2 photocatalysts. S-doped and N-doped TiO 2 loaded with Fe 2O 3 nanoparticles have also been prepared. These photocatalysts showed activity under a wide range of wavelengths of irradiation. Action spectra of photochemical reaction rate as a function of the incident light wavelength for oxidation of acetic acid on S-doped TiO 2 was studied.The photocatalytic activities of S-doped and N-doped TiO 2 photocatalysts loaded with Fe 2O 3 nanoparticles for oxidation of acetic acid in aqueous phase and acetaldehyde in gas phase are markedly improved compared to those of doped TiO 2 without loading of Fe 2O 3 nanoparticles under a wide range of incident light wavelengths. The optimum amount of Fe 2O 3 nanoparticles loaded on S-doped TiO 2 particles was different from that on N-doped TiO 2 for oxidation of organic compounds. The relationship between reaction rate of photocatalytic oxidation of acetaldehyde on doped TiO 2 loaded with Fe 2O 3 nanoparticles and amount of Fe 2O 3 nanoparticles is discussed.

Preparing Levoglucosan Derived from Waste Material by Pyrolysis

Waste newspaper and waste cotton were pyrolyzed in tubular furnace pyrolysis equipment. This experiment is directed to the influence of pyrolysis temperature on yield of levoglucosan and other pyrolysis products from waste material. The results show that levoglucosan yield is correlate to pyrolysis oil yield. The highest yield of levoglucosan can be obtained when the pyrolysis temperature was around 420°C in waste newspaper and 420°C in waste cotton. Bio-oil, gas, and char yields of different temperature were also determined. The HPLC analysis shows main composition is acetic acid in aqueous phase while relatively large proportion is levoglucosan in nonaqueous phase.

Extraction Equilibria of Formic and Acetic Acids from Aqueous Solution by Phosphate-Containing Extractants

The purpose of this work is to study the feasibility of extraction and recovery of formic acid and acetic acid in the industry synthesis of these two acids. In this work, extraction equilibria of formic and acetic acid with kerosene solutions of such phosphate-containing extractants as trialkylphosphine oxide (TRPO) and tributyl phosphate (TBP) were studied. The solutions of formic and acetic acid in aqueous phase at equilibira ranged from 0.4 mol·L-1 to 8 mol·L-1. The influences of temperature on extraction equilibria were also studied. A model was proposed to describe the equilibria by postulating the structure of the complexes. The parameters in the model were obtained by fitting the experimental data, and the values predicted by this model are very close to the measured results.

REMOVAL OF ACETIC ACID WITH AMINE EXTRACTANTS FROM FERMENTATION BROTH USING HYDROPHOBIC HOLLOW-FIBER MEMBRANE CONTACTOR

The organic solvent with a high partition coefficient toward acid extraction must be selected to increase the efficiency of extraction of acetic acid in aqueous phase. Amine extractant plays a major role in the reactive extraction process at the interface between aqueous phase/organic phases. Therefore, it has been investigated that an effect of addition of various amines such as di-ethylamine (DEA), tri-ethylamine (TEA), and tri-n-octylamine (TOA) to organic phase could increase the extraction performance due to increasing partition coefficient. The effect of temperature with TOA content of 0 to 40 wt-% on extraction process of acetic acid was observed. The removal efficiency of acetic acid in aqueous phase increased with temperature. However, the maximum value of extraction performance was different according to experimental conditions, such as the choice of organic solvent, temperature, and TOA content. In the case of methyl isobutyl ketone (MIBK)/TOA system and chloroform/ TOA used in organic phases, the maximum value of removal of acetic acid showed 64 wt-% and 53 wt-% at 40 wt-% TOA content and 25°C, respectively. In 2-octanol/TOA system, the maximum removal efficiency of acetic acid was 67 wt-% at 30 wt-% TOA and 50°C. On the basis of the energy efficiency, the optimal condition of organic phase for the extraction of acetic acid in aqueous phase was determined to be 40 wt-% MIBK/TOA at 25°C. Using the membrane extraction process with a hollow-fiber membrane contactor, the overall mass transfer coefficient was calculated by Wilson-plot method under the assumption of constant partition coefficient. These values show a significant increase in mass transfer rate with increasing the TOA content. Additionally, an improvement of extraction performance was established by multiplying the diffusion coefficient and partition coefficient of solutes.