Mixed Solvent Extraction Research Articles

Preliminary Study at Lipids Extraction Technology from Municipal Sludge by Organic Solvent

With the development of our society, waste water treatment ratio is going higher and as a result there are more and more sewage sludge. Because of its high water content, containing heavy metal and some virus, sewage sludge has been a serious environmental problem. Considering the energy crisis and serious environmental pollution, and because of the fact that there are considerable lipids in sewage sludge, which can be turned into biodiesel by esterification or transesterification, we proposed a new solution for sewage sludge problem which is to make biodiesel from sewage sludge. The whole process is divided into three steps: heat-drying, extraction of lipids and transesterification. In this research, we are going to discuss the extraction step. We extracted lipids from sewage sludge by referring to the national standard for food. We used many organic solvents such as ether, hexane, acetone, chloroform – methanol. Then we will discuss that which solvent will be more favorable to extract the lipids from the sludge by measuring the quantity of the lipids we have obtained. After the experiment, we have found that as to the single solvent extraction, bromo-propane solvent has the highest extraction effect, the other sort of the solvents are ether, toluene, N-hexane, petroleum ether. While, as to mixed solvent extract, the hexane – ethanolthe solvent has higher efficiency than other mixed solvent. The results show that mixed solvent has higher efficiency than the single solvent and the polar solvents are easier to extract more lipids than the non-polar solvents from the sludge.

An Investigation of the Effect of Pre-swelling on the Extraction Yield of Two Different Ranked Turkish Coals

In this article, the effect of pre-swelling on the extraction yield of two Turkish coals was investigated. Supercritical toluene extraction and carbon disulfide/N-methyl-2-pyrrolidinone mixed solvent extraction at room temperature were the extraction methods employed. Ten different solvents were used to study the swelling behaviors of the coals. The swelling ratios were found dependent on the coal type, solvent basicity, and steric effect of the solvent used. The best swelling solvent identified was ethylenediamine for two coal samples. Pre-swelling enhanced the conversion and oil yield in supercritical toluene extraction. However, when using the mixed solvent extraction, the effect of pre-swelling was dependent on coal rank. Pre-swelling with ethylenediamine enhanced the extraction yield of Soma lignite while it decreased that of Nasifoglu coal.

Alternative Techniques for Defatting Soy: A Practical Review

Hexane extraction is the most common technique used to remove oil from full fat soy materials in the production of both soy oil and defatted soy. The popularity of hexane is based on its high oil extraction efficiency and its availability. The solvent, however, has some considerable economic, environmental, and safety drawbacks. A review of alternative soybean defatting techniques is carried out through the description of four main technological approaches including: (1) alternative organic (carbon-based) solvent extraction, (2) aqueous extraction, (3) supercritical carbon dioxide (SC-CO2) extraction, and (4) enzymatically aided extraction. Through detailed discussions of experimental results, the advantages and disadvantages of each approach are presented. The optimum oil yield for the various extraction techniques discussed ranges from as high as 26.0% for mixed organic solvent extraction of full fat soy flour to as low as ∼7% for some enzymatic treatments of full fat soy brokens extracted by mechanical pressing. An environmentally friendly, safe, and cost-efficient alternative technique has yet to be developed to replace hexane extraction. Current aqueous and SC-CO2 techniques show promise but require further research and development to ensure their practicality in terms of industrial processing.

Unusual sesquiterpene lactones with a new carbon skeleton and new acetylenes from Ajania przewalskii

Four new compounds, a noreudesmanolide (1), a guaianolide (4), and acetylenes (7–8), together with 16 other known compounds, were isolated from Ajania przewalskii. The novel sesquiterpenolide (1) possesses a rare carbon skeleton. Acetylation of 1 gave 1a. New compounds were elucidated as 1β-hydroxyl-2-noreudesm-4(15)-en-5α,6β,7α,11αH-12,6-olide (1), 1β-acetoxyoxyl-2-noreudesm-4(15)-en-5α,6β,7α,11αH-12,6-olide (1a), 8α-angeloyloxyl-3α,4α-dihydroxyguaia-1,9,11(13)-trien-6,12-olide (4), (E)-3β,4α-dihydroxyl-2-(2′,4′-hexadiynylidene)-1,6-dioxaspiro[4,5]decane (7) and 2-hydroxyl-2-[(E)-1α,2β,3-trihydroxyl-3-nonaene-5,7-diyne]-4H-pyran (8), by chemical and spectroscopic methods, including HRESIMS, 1D and 2D NMR. Cytotoxicity of nine compounds was assessed by their effects on selected cancer cell lines, K562, K562/ADM, BGC-823, and Hep-G2 cells. Phenolic acid 12 exhibited strong activity against K562 and K562/ADM cells and sesquiterpenolide 3 strong activity against K562/ADM cells. Radical-scavenging activities of 12 compounds, the mixed solvent extract (petrol ether–ether–methanol = 1:1:1), and the n-butanol extract were determined by ABTS and DPPH radical-scavenging assays. Phenols and coumarins (11–16), MSE, and n-BE displayed significant antioxidation (IC50 < 20 μg/ml).

Preparation and Structural Characterization of a Needlelike Carbon from the Refined Coal Tar Pitch

A refined coal tar pitch with softening point of 33oC was obtained by a mixed solvent extraction method. The pitch was carbonized at 500oC to get micrometer carbon material with needlelike structure. The carbonized produce was further calcined at 1500oC for 30h. The resultant product was characterized by SEM, OM, EDS and XRD. Experimental results indicated that a mixed solvent extraction method could effectively get rid of primary quinoline insoluble (QI). SEM and OM examinations showed that there were more than 70% fibrous structures and a small amount mosaic structures. The size of the fibrous structure was greater than 150μm in length and less than 30μm in width. The result of EDS exhibited that the material mainly consisted of carbon. XRD analysis revealed that there was a sharp diffraction peaks at 26.5oC, which was corresponded to the (002) plane of graphite structure.

Extraction and HPLC Characterization of Chlorogenic Acid from Tobacco Residuals

Chlorogenic acid is a highly valuable natural polyphenol compound used in medicine and industries. Its current commercial sources are from plant extracts of Lonicera japonica Thunb and Eucommia ulmoides Oliver. These sources are limited and expensive. On the other hand, tobacco residuals contain chlorogenic acid and other natural polyphenol compounds. Large quantities of tobacco residuals are produced each year as waste materials from tobacco manufacturing, potentially providing an alternative commercial source of chlorogenic acid and other valuable compounds. In this paper, microwave and ultrasound extractions of chlorogenic acid with mixed solvent were studied. Total polyphenol concentrations in extract solutions obtained with different extraction methods were analyzed with the method of ferrous tartrate and UV‐Vis spectrophotometry and compared. The extraction solutions were also characterized for polyphenol compositions with the method of HPLC. Experimental results indicated that high extract concentrations of chlorogenic acid were obtained with a mixed solvent of acetone and water (1:2 v/v). A total polyphenol concentration of up to 4.87 mg/ml and a chlorogenic acid concentration of up to 2.12 mg/ml were achieved. The application of microwave and ultrasound significantly increased the extract concentrations. The extraction time needed was also much reduced. HPLC analysis indicated that acetone water mixed solvent extraction achieved much higher relative concentrations of chlorogenic acid to other compounds in the extract solutions. These results indicted that fast and effective extraction of chlorogenic acid from tobacco residuals were achieved.

Study on the hydrothermal treatment of Shenhua coal

In this paper, the hydrothermal treatment of Shenhua coal was carried out under 0.1 MPa (initial pressure) nitrogen and different temperature. Effects of hydrothermal treatment on the structure and the hydro-liquefaction activity of Shenhua coal were investigated by the ultimate and proximate analyses, the FTIR measurements and TG analyses of hydrothermally treated coals, and the characterizations of extraction and swelling properties, and the batch hydro-liquefaction of treated coal were also carried out. The results indicate that hydrothermal treatment above 200 °C can increase the hydrogen content of treated coal and decrease the yield of volatiles and the content of ash, especially a large amount of CO and CH 4 are found in gas products obtained by the hydrothermal treatment above 250 °C. Hydrothermal treatment disrupts the weak covalent bond such as ether, ester and side-chain substituent by hydrolysis and pyrolysis, and changes the distribution of H-bond in coal. The swelling ratio and the Soxhlet extraction yield of treated coal decrease with the increase of hydrothermal treatment temperature. The conversion of liquefaction and the yield of CS 2/NMP mixed solvent extraction at ambient temperature are enhanced by hydrothermal treatment at 300 °C. Therefore hydrogen donation reactions and the rupture of non-covalent bond and weak covalent bonds present in the process of hydrothermal treatment resulting in the changes of structure and reactivity of Shenhua coal. The results show that the hydro-liquefaction activity of Shenhua coal can be improved by hydrothermal pretreatment between 250 °C and 300 °C.

Pyrolysates of raw vitrinites and their residues after CS2-NMP solvent extraction and its significance for petroleum geology

Binary solvent (CS2-NMP) has extreme high extraction ability to coals, and it can extract most bitumens out of coals and vitrinites. And large amount of messages on side chains and their distribution character in vitrinites should be acquired through flash pyrolysis before and after binary solvent (CS2-NMP) extraction. A few low maturated coals have been selected and vitrinites are handpicked from coals. Then vitrinites have been extracted using different solvents in the order of polarity. Flash pyrolysis-Gas Chromatography/Mass spectrum has been applied to samples. The result shows that CS2-NMP is efficient for the extraction of vitirnites, giving much higher extraction yield than common solvents. Production ratio of liquid hydrocarbons in pyrolysates of vitrinites extracted with CS2-NMP is lower than that of raw vitrinites. And relative ratio of each component in pyrolysates has changed apparently. Production ratio of aliphatic hydrocarbons, especially those long chain aliphatics have decreased much after mixed solvent extraction. It shows that bitumens extracted with CS2-NMP have largely contributed to pyrolysates, especially those aliphatics in pyrolysates.

Gel Formation in Natural Rubber Latex: 2. Effect of Magnesium Ion

Abstract The effect of Mg2+ ions on the gel formation in fresh and commercial high ammonia natural rubber latices (FL-latex and commercial HA-latex) was analyzed from the gel content and 2+ content after treatment with (NH4)2SO4. The gel content of rubber from commercial HA-latex decreased significantly after (NH4)2SO4 treatment comparable to that of FL-latex. Long-storage commercial HA-latex containing 50% gel fraction showed no decrease in 2+ content after (NH4)2SO4 treatment. This gel fraction was not solubilized in toluene by the treatment of a proteolytic enzyme in latex or ethanol/toluene mixed solvent extraction of rubber. The 2+ content of rubber in long-storage commercial HA-latex, 0.005% (w/w rubber), decreased after treatment with (NH4)2SO4, while the same treatment showed little change on FL-latex, 0.035%. The toluene soluble fraction of these latices showed a decrease in the Mn value with an increase in the (NH4)2SO4 concentration. The gel content of FL- and HA-lattices increased with an increasing storage period in the presence and absence of (NH4)2SO4. The initial rate of increase in the gel content was slow in the case of FL-latex. These findings indicate that the gel fraction in HA-latex is partly formed by ionic crosslinks caused by 2+ ions. Whereas, the gel phase in long-storage commercial HA-latex is presumed to be a hard gel predominantly formed by covalent bonding.

Spectroscopic characterisation of indium(III) chloride and mixed ligand complexes

Acidic solutions of InCl 3 plus InBr 3 contain mixed halide complexes and solvent extraction yields the four-coordinate anions InCl n Br 4− n − whose ν(InCl) and ν(InBr) modes are reported. Two solid products of InCl 3 with 15-crown-5 have been identified; crystallisation from aqueous HCl gave a molecular adduct containing InCl 3(H 2O) 2, whereas the ionic complex [InCl 2(15-crown-5)][InCl 4] was produced under anhydrous conditions. The vibrational spectra are assigned.

Metal ion recognition. The interaction of cobalt(ii), nickel(ii), copper(ii), zinc(ii), cadmium(ii), silver(i) and lead(ii) with N-benzylated macrocycles incorporating O2N2-, O3N2- and O2N3-donor sets

The interaction of cobalt(II), nickel(II), copper(II), zinc(II), cadmium(II), silver(I) and lead(II) with a series of mixed-donor, N-benzylated macrocyclic ligands incorporating O2N2-, O3N2- and O2N3-donor sets has been investigated. The log K values for the respective 1 ∶ 1 complexes in 95% methanol (I = 0.1 mol dm−3; Et4NClO4, 25 °C) have been determined potentiometrically and the results compared with the values obtained previously for the parent (non-benzylated) macrocyclic systems. Examples of N-benzylation of individual parent macrocycles leading to enhanced discrimination for silver(I) are presented. In the case of a dibenzylated O3N2-ring and a tribenzylated O2N3-ring, both 17-membered, high selectivity for this ion was observed relative to the other metal ions investigated. Competitive mixed-metal transport experiments across a bulk chloroform membrane have been performed using the benzylated derivatives as ionophores. For each experiment the source contained equimolar concentrations of the above metal ions and transport was performed against a pH gradient; the aqueous source and receiving phases were buffered at pH 4.9 and 3.0, respectively. In parallel to the log K results, transport selectivity for silver(I) was exhibited by the di- and tri-benzylated ligands mentioned above. The remaining ligands proved to be poor ionophores, showing no significant metal ion transport under the conditions employed. In a further study, high silver ion (transport) selectivity was maintained when the above tribenzylated ligand was incorporated as the ionophore in a polymer inclusion membrane system. Single metal and mixed (seven-metal) solvent extraction experiments employing similar aqueous source and chloroform phases to those used in the bulk membrane transport runs have also been performed for the tribenzylated ligand derivative; significant selectivity for silver was again maintained in these solvent extraction experiments. An X-ray study of [AgL]ClO4 (where L is the above-mentioned dibenzylated derivative) confirms that all donor atoms of the macrocycle coordinate to the silver ion; the latter is five-coordinate with the complex cation exhibiting a highly distorted trigonal bipyramidal geometry.

Modification of Model Structures of Upper Freeport Coal Extracts Using 13C NMR Chemical Shift Calculations

The extract from carbon disulfide/N-methyl-2-pyrrolidinone mixed solvent extraction of Upper Freeport coal at room temperature was fractionated with acetone and pyridine into three fractions, and solid-state 13C NMR measurements of these fractions were made. Model structures for the three extract fractions constructed by Takanohashi et al. (Energy Fuels 1998, 12, 1168) were estimated using the NMR chemical shift calculation method. By comparing the spectra calculated for the model structures with the observed spectra, some corrections were made to the chemical structures of the original models to fit their spectra. Compared with the observed spectra, for the acetone-soluble fraction (AS), the model structure was richer in nonprotonated aromatic carbon and β methylene carbon, and poorer in protonated aromatic carbon and methyl carbon, and, for the acetone-insoluble−pyridine-soluble fraction (PS) and pyridine-insoluble−mixed-solvent-soluble fraction (PI), the spectra calculated for the model structures showed higher fractions for nonprotonated aromatic carbon and methylene carbon, and lower fractions for methyl carbon. We proposed modified model structures based on NMR chemical shift calculations for the three fractions.

Irreversible Structural Changes in Coals during Heating

A differential scanning calorimetry (DSC) study on the extraction residues of coals giving different extraction yields (which were prepared by changing the solvent composition of a carbon disulfide-N-methyl-2-pyrrolidinone mixed solvent extraction) was carried out. For the residues from Upper Freeport coal (APCS-1) with extraction yields lower than 30 wt % (daf), an endothermic peak similar to that given by the raw coal was observed around 350 °C. This endothermic peak disappeared on the second and third scans, indicating that the peak is due to irreversible structural changes in coals. For the residues from the high extraction yield experiments, the peak was not observed up to 400 °C, even during the first scan. The reason for these endothermic peaks was discussed from the relationship among the extraction, swelling, and structural changes of coals.

Study on thermoplasticity of Coking Coals from Solvent Extraction and Viscoelasticity Measurements

In order to investigate thermoplasticity of coals during heating, heat-treated coals were extracted with carbon disulfide-N-methyl-2-pyrrolidinone (CS2-NMP) mixed solvent at room temperature. The highest extraction yields obtained for each coal heat-treated from 390-430°C had a linear relationship with its maximum fluidity measured by Gieseler plastometry. The amount of pyridine insoluble components of CS2-NMP mixed solvent extract was also proportional to Gieseler maximum fluidity, suggesting that coal fluidity is affected by the presence of the heavier components. Dynamic viscoelastic measurement using a rheometer was applied to coal during heating. Elastic (G') and viscous (G'') moduli, and tan δ in which δ is a phase delay of a stress to a strain applied to a coal pellet were determined at 300-550°C. The temperatures corresponding to softening, maximum fluidity state, and resolidification of coals could be estimated from a maximum or minimum of G' and G'' observed at G' or G''- temperature profiles, and they are in fair agreement with those measured by Gieseler plastometry for the coals used. Tan a also gave a maximum near maximum fluidity temperatures estimated from G' and G''.

Simulation of Interaction of Coal Associates with Solvents Using the Molecular Dynamics Calculation

The extract obtained from a carbon disulfide−N-methyl-2-pyrrolidinone mixed-solvent extraction at room temperature for Upper Freeport coal (APCS1) was fractionated with acetone and pyridine into three fractions, i.e., acetone-soluble (AS), acetone-insoluble−pyridine-soluble (PS), and pyridine-insoluble (PI) fractions. For the three extract fractions, the model structures based on the structural parameters were constructed, and the energy-minimum conformation was calculated by the molecular mechanics and molecular dynamics methods. As the fractions got heavier, more stable associates formed among the model structures by several cooperative interactions through aromatic−aromatic interactions, hydrogen bonds, and electrostatic interactions. Furthermore, the molecular dynamics calculation in the presence of pyridine showed that a part of the coal associates was broken by their interactions with pyridine molecules. When benzene or methanol was used as the solvent, the breaking of coal associates did not take p...

4-4.混合溶媒抽出による石炭の軟化溶融機構(Session(4)エネルギー工学研究会)

4-4.混合溶媒抽出による石炭の軟化溶融機構(Session(4)エネルギー工学研究会)

Batch Extraction Studies of Cationic and Anionic Heavy Metallic Species by a Mixed Solvent Extraction System

ABSTRACT Removal of toxic heavy metals from wastewaters and their recovery is a challenging problem. Simultaneous and synergistic batch extraction from water of copper present as a cation (Cu2+) and Cr6+ present as an anion (HCr2O) into a mixed solvent extraction system have been studied. The mixed solvent extraction system consists of the diluent kerosene, the cation exchanger LIX 84, and trioctyl amine (TOA) which extracts anions via ion-pair formation with a proton. Highly efficient extraction has been achieved for both copper and chromium. Simultaneous extraction of two cations, Cu2+ and Zn2+, as well as the anionic form of Cr6+, (HCr2O), has also been studied using mixtures of LIX 84, di-2-ethylhexyl phosphoric acid (D2EHPA), and TOA in the diluent kerosene. For an appropriate mixture composition, all three metallic ionic species can be simultaneously extracted with high efficiency. The extent of complexation between the basic extractant, TOA, and the acidic extractant/s is important in determining the extraction efficiency. A model developed for the extraction of Cu2+ using a mixed solvent extraction system provides a reasonable description of the observed extraction behavior and provides a first step for modeling.

Characterization of the Soluble and Insoluble Fractions of Upper Freeport Coal in NMP/CS2 and Pyridine Using Small Angle Neutron Scattering

Small angle neutron scattering (SANS) was used to characterize the solution structure of coal extract/solvent systems as well as swelling-induced structural changes in the nonextractable residues derived from the Upper Freeport (UF), medium-volatile bituminous, coal. Studies were performed on the pyridine soluble (PyS) fraction dispersed in perdeuterated pyridine (dPy); the PyS fraction dispersed in the mixed solvent [dm, perdeuterated N-methylpyrrolidinone (NMP) and carbon disulfide, CS2], and the mixed solvent soluble fraction (MS) in dM. No coherent scattering was observed for the UF-MS/dM sample in the accessible Q range, indicating that the solution contains no large particles or aggregates. Strong coherent scattering was observed for the UF-PyS/dPy and UF-PyS/dM solutions, indicating the presence of large particles, presumably molecular aggregates. Comparison of the SANS behavior of the three samples suggests that there exist molecular components intrinsic to the pyridine insoluble NMP/CS 2 soluble fraction that may play a significant role in the enhanced solvation of the mixed soluble fraction of the Upper Freeport coal in NMP/CS 2 solvent. SANS analysis of the dry and pyridine (d5)-swollen UF-PyI and UF-MI residues revealed significant structure evident by power-law scattering behavior in the low Q region of both sets of samples. In the case of the UF-MI samples, significant scattering intensity was also observed in the intermediate Q region. Significant structural changes were observed in the UF-MI fractions upon swelling in pyridine, whereas minimal structural changes were observed in the case of UF-PyI sample during solvent swelling. These results reveal that the physical consequences of mixed solvent extraction are significantly different from those due to pyridine extraction.

96/05730 Mixed solvent extraction yield and structural changes of heat-treated coals and their relation to coal fluidity

96/05730 Mixed solvent extraction yield and structural changes of heat-treated coals and their relation to coal fluidity

加熱処理炭の混合溶媒抽出率と構造変化の流動性との関連

加熱処理炭の混合溶媒抽出率と構造変化の流動性との関連