Solvent extraction of ethanol from aqueous solutions using biobased oils, alcohols, and esters

Distribution coefficients and separation factors were determined for the partitioning of ethanol and water from aqueous mixtures into several vegetable oils and their fatty alcohol and fatty ester derivatives. Castor oil, ricinoleyl alcohol, and methyl ricinoleate all show higher ethanol distribution coefficients, and similar or reduced separation factors, relative to other oils and derivatives studied here or reported by others. Of particular interest, ricinoleyl alcohol has an ethanol distribution coefficient 50% higher than that of oleyl alcohol, a commonly studied solvent for ethanol extraction from fermentation broths.     

Effect of ethanol content on supercritical carbon dioxide extraction of caffeine from tea stalk and fiber wastes

This study presents the effect of ethanol content on supercritical carbon dioxide extraction of caffeine from tea plant wastes. Tea stalk and fiber wastes of Turkish tea plants that have no economical value were evaluated as raw material throughout the caffeine extraction experiments. These wastes were supplied from tea factory marked “Çaykur” in the east blacksea region. They were separately ground, sieved and dried at 105 °C temperature in an oven. Parameters affecting caffeine leaching from tea wastes were determined to be, ethanol flow rate, extraction time, extraction temperature, carbon dioxide flow rate, process pressure and particle size. The maximum yield of caffeine from tea stalk wastes and fiber wastes were 14.95 mg/g tea stalk and 18.92 mg/g tea fiber, respectively. When the supercritical extraction conditions used of ethanol as cosolvent have been compared with the conditions of used only carbon dioxide, approximately the same yield has been reached at 2 h extraction period instead of 7 h. Beside of saving of the time and the amount of carbon dioxide, the supercritical extraction yield with cosolvent increase had been recorded as 62.5% and 63.1%, respectively, in comparison with the chloroform extraction as conventional method of tea stalk and fiber wastes.     

天然红色素的提取工艺研究

对天然红色素的提取工艺进行了研究,通过单因素试验和L9(33)正交试验,研究了溶剂种类、浸取温度、固液比对天然红色素提取率的影响.结果显示温度是影响提取率的主要因素,最佳工艺条件是丙酮为溶剂、浸取温度35 ℃、固液质量比1∶5,红色素的浸出率可达到92.3%.     

用乙醇-水从双液相棉粕中提取棉子糖的研究

用双液相萃取工艺处理后的棉籽粕为原料,乙醇-水溶液为溶剂进行了棉子糖的提取试验,并考察了影响浸出率的因素。在单因素实验的基础上,通过正交实验得出优化后的提取工艺条件为:乙醇体积分数为70%,提取温度60℃,提取时间150 m in,物料溶剂比1∶14(即每克物料需14 mL溶剂)。在此工艺条件下,棉子糖的浸出率为92.5%。     

Supercritical CO2 and low-pressure solvent extraction of mango (Mangifera indica) leaves: Global yield,extraction kinetics,chemical composition and cost of manufacturing

Low-pressure solvent extraction (LPSE) and supercritical fluid extraction (SFE) were used to obtain extracts from mango (Mangifera indica) leaves. Kinetics curves were determined for both methodologies. The extracts chemical compositions and manufacturing costs were determined for both processes. Global yield isotherms for SFE process were determined at 10–40 MPa and 313–323 K. The highest yield was 2.24% at 30 MPa and 323 K; the LPSE yield (9.3%) was almost three times higher than that of SFE (3.6%). Thin layer chromatography showed that mango leaves extracts have several classes of compounds as alkaloids, flavonoids and terpenoids, recovered by both methods. The cost of manufacturing (COM) mango leaves extracts were US$ 32/kg and US$ 92/kg for LPSE and SFE, respectively.     

溶剂脱酚装置降低粗苯溶剂消耗初探

以粗苯为溶剂萃取脱酚，粗苯的主要消耗是其在处理后氨水中溶解的损失。适当降低萃取操作温度，可以明显降低粗苯消耗，而不会影响其脱酚效率。     

Solvent extraction and purification of rosmarinic acid from supercritical fluid extraction fractionation waste: Economic evaluation and scale-up

Industry is increasingly interested in natural food preservatives, antimicrobial, and antioxidants due to their beneficial effects. The use of plant waste also presented itself to be a great opportunity in recovered bioactive compounds remaining in the residue. In this work, bioactive compounds were obtained from Rosmarinus officinalis in two different ways: firstly the supercritical fractionated rosemary extract with different composition was obtained from the plant material, and secondly a potent antioxidant-rosmarinic acid (RA) – was successfully extracted from the plant waste. A purification process scale-up of RA was proposed using GRAS solvent, and an economic evaluation was made for the overall process. A complete process to obtain bioactive compounds, antimicrobial (supercritical fluid extraction and fractionation extraction) and antioxidant (solvent extraction) was developed.     

Supercritical extraction of grape seed oil at industrial-scale: Plant and process design,modeling, economic feasibility

The aim of this paper is to present the results of a study on the possible use of exhausted grape marc for obtaining grape seed oil by means of the supercritical technology. An industrial-scale supercritical extraction plant (three extractors in series working in the counter-current mode) has been designed based on the availability of grape seeds of a region in the north of Italy, namely 3000 ton/year (3 × 10⁶ kg/year). The process has been analyzed in depth and modeled and the results indicate that the proposed industrial application could be economically interesting: the breakeven point, which makes the process economically sustainable, is a value of 5.9 €/kg for the supercritical extracted grape seed oil.     

Process analysis and optimisation of hybrid processes for the dehydration of ethanol

Promising hybrid processes for ethanol dewatering consist of different combinations of distillation with adsorption and/or vapour permeation. This paper presents an analysis and optimisation of these hybrid processes using non-equilibrium models and an evolutionary algorithm. Four different membrane assisted configurations are compared with a benchmark process consisting of distillation and pressure swing adsorption. In total 12 cases were investigated while assuming different feed and product compositions at different production capacities: three ethanol mass fractions in feed 45, 80, 92 wt.%, two product purities 99.6, 99.95 wt.% and two production capacities 25,000, 250,000 m³/year. The influence of decisive operating and structural variables on important target variables such as total membrane area is demonstrated. Finally, the processes are evaluated regarding operating costs and energy consumption depending on product purity and production capacity. The operating costs of the membrane assisted configurations differ only in a small range of −3% to 6% from those of the benchmark. The energy consumption of the membrane assisted configurations without distillation is up to 30% lower compared to the benchmark. Especially the combination of vapour permeation and adsorption is a promising alternative allowing for producing ethanol with high purities at lower operating pressures compared to the vapour permeation as stand alone process.     

A simple model to assess the contribution of alloyed and non-alloyed platinum and tin to the ethanol oxidation reaction on Pt-Sn/C catalysts: Application to direct ethanol fuel cell performance

A simple model is proposed to evaluate the contribution of alloyed and non-alloyed platinum and tin to the ethanol oxidation reaction on Pt-Sn/C catalysts for direct ethanol fuel cells. On the basis of the model, the ethanol oxidation on partially alloyed catalysts occurs through a dual pathway mechanism, separately involving the Pt₃Sn phase and Pt-SnO_x. The model, validated by experimental data, can predict the performance of a single direct ethanol fuel cell by varying the Sn content and/or the degree of alloying of Pt-Sn/C catalysts used as the anode material.     

Esterification with ethanol to produce biodiesel from high acidity raw materials: Kinetic studies and analysis of secondary reactions

In this work, the esterification reaction of free fatty acids (FFA) in sunflower oil, coconut oil and concentrated FFA, with ethanol, methanol and ethanol 96%, using homogeneous acid catalysts to produce biodiesel is studied. Kinetic parameters are estimated with a simplified model, and then used to predict the reaction behavior. Reactions other than the reversible esterification are considered to explain the behavior that this system displays. Such reactions are the triglycerides conversion by acid catalyzed transesterification and hydrolysis. In addition, we include kinetic studies of the reaction that occur between the sulphuric acid and methanol (or ethanol), forming mono and dialkylsulphates. This reaction produces water and consumes methanol (or ethanol), and consequently has a direct impact in the esterification reaction rate and equilibrium conversion. The concentration of sulphuric acid decreases to less than 50% of the initial value due to the reaction with the alcohol. A minimum in the acidity due to the free fatty acids as a function of time was clearly observed during the reaction, which has not been reported earlier. This behavior is related to the consecutive reactions that take place during the esterification of FFA in the presence of triglycerides. The phase separation due to the presence of water, which is generated during the reaction, is also studied.     

Effect of solvent (CO2/ethanol/H2O) on the fractionated enhanced solvent extraction of anthocyanins from elderberry pomace

The management of agro-industrial residues is an important issue for environmental reasons and the reuse of byproducts represents a good alternative, especially if it is conjugated with green technologies and the production of valuable products. Portuguese elderberry pomace is rich in anthocyanins with therapeutic properties that confer to this byproduct potential to be applied in the food and pharmaceutical industries. Fractionated high pressure extractions from elderberry pomace were performed using supercritical CO₂ extraction, followed by enhanced solvent extraction (ESE) with diverse CO₂/ethanol/H₂O solvent mixtures (0-90%, 0.5-100%, 0-95%, v/v/v), at 313 K and 21 MPa, in order to obtain anthocyanin-rich fractions. The ESE solvent mixtures had a substantial effect on extracts yield and composition. The maximum extraction yield (24.2%), total phenolic compounds (15.8% gallic acid equivalents), total flavonoids (8.9% epicatechin equivalents), total anthocyanins (15.0% cyanidin-3-glucoside equivalents) and antioxidant activity (IC₅₀ of 21 μg) achieved highlight the great potential of elderberry pomace for valuable applications.     

Phase equilibrium studying for the supercritical fluid extraction process using carbon dioxide solvent with 1.35 mole ratio of octane to ethanol mixture

Supercritical fluid extraction is a clean environmental chemical engineering process that has been given an interest to many researchers worldwide. The assessment of the feasibility of the extraction process utilizing a near critical solvent would be speeded up if it is possible to predict solubility data. Solubility data were measured for carbon dioxide with a mole ratio 1.35 of octane to ethanol using a phase equilibrium loading re-circulating high-pressure type apparatus at pressures up to 100 bar and at temperature 75 °C. The experimental data were then compared with calculated theoretical data which is calculated form the regular solution equations. A thermodynamic procedure is employed to each phase by applying activity coefficient expressions related to interaction parameters which are dependent on the pressure.     

基于价值工程原理的镁合金有机涂层体系的技术经济评价

在选择镁合金防护涂层体系时,既要考虑其性能,又要兼顾成本。本文在镁合金基体上制备了12种不同工艺的有机涂层体系,运用价值工程原理对其在2种典型服役条件(海洋环境和一般大气环境)下的技术经济指标进行了评价。结果表明,服役条件对涂层体系的技术经济性能有重要的影响。丙烯酸、陶瓷有机硅涂层体系的技术经济系数随耐蚀性权重的增大而减小,而环氧树脂、有机硅涂层体系则相反。在预处理方面,无铬转化具有最佳的技术经济性;在涂料品种方面,环氧树脂涂层体系的技术经济性能优势明显。无铬转化/环氧树脂涂层体系的综合技术经济性能最佳。     

Process intensification in extraction by liquid emulsion membrane (LEM) process: A case study; enrichment of ruthenium from lean aqueous solution

Process intensification in extraction as a unit operation can be realized through liquid emulsion membrane (LEM) process by combining extraction and stripping in one stage eliminating the need of stripper. LEM technique is very useful to enrich very lean aqueous phase containing precious metal to aid the recovery process. The technique is illustrated by applying the same to enrich platinum group noble metal, ruthenium (Ru) from its aqueous solution. The liquid membrane phase consisted of extractant (trioctylamine) dissolved in liquid paraffin modified with 1-octanol and the surfactant used was Monemul 80. The strip phase found to be very effective was perchloric acid. To facilitate extraction tin(II) chloride was added to the aqueous feed phase containing Ru at 20 ppm level. Various process parameters affecting the performance of LEM process such as extractant, surfactant, strip phase concentrations, the batch extraction time, the treat ratio and the speed of agitation were studied at bench scale to aid process development.     

Effective extraction in packed column of ethanol from the azeotropic mixture ethanol + hexane with an ionic liquid as solvent

Ionic liquids (ILs) are playing an increasingly important role in separation science. In this account, the application of ILs in all areas of separation including extraction, gas chromatography, and supported liquid membrane processes is highlighted. 1,3-Dimethylimidazolium methyl sulfate [MMIM] [MeSO₄] is suitable for use as solvent in the petrochemical extraction process for the removal of ethanol from its mixture with hexane. The knowledge of liquid–liquid equilibria (LLE) is essential for the design of the separation technique applied. For this reason, the experimental LLE for the ternary system hexane + ethanol + [MMIM] [MeSO₄] has been determined at 298.15 K. The solvent capacity of the [MMIM] [MeSO₄] is compared with other ILs. Extraction process with this solvent is simulated using conventional software and the obtained results are shown. Experimental data are obtained in a laboratory-scale packed column extraction system for the separation of this azeotropic mixture using [MMIM] [MeSO₄]. IL could be recycled and then the separating process reduces the energy consumption greatly.     

Process analysis of the extract unit of vacuum residue through mixed C4 solvent for deasphalting

By employing the EXTRACT module in Aspen Plus Software with the aid of selected PSRK equation from our previous work [W. Li, P. Du, F. Cao, W. Ying, D. Fang, Simulation and optimization of the extract segment of solvent deasphalting plant, Computers and Applied Chemistry, 26 (2009) 455–460] [18], this work simulated a solvent deasphalting (SDA) process with mixed C4 solvent and the feedstock of vacuum residue (VR) obtained from a mixed crude oil (Zhongyuan oil:Tahe oil:Changqing oil:Oman crude oil:Zafiro crude oil = 35:5:2:40:18, wt/wt). The feed of VR was lumped as paraffinic, primitive and aromatic components according to their calculated K_UOP values. The relative errors not more than 3.94% illustrated the simulated results are comparable with the industrial data for both feedstock (VR and mixed C4 solvent) and products (deasphalted oil—DAO and deoiled asphalt—DOA). The DAO yield was predicted to reduce to 47.2% from 58.0% with increasing temperature of mixed C4 solvent from 100 to 120 °C under operating model-I, but increased from 51.6% to 56.1% with solvent–VR ratio up to 6.5 from 4.5. In addition, a heavier mixed C4 solvent would facilitate remarkable improvement of DAO yield but deteriorate its quality.     

Methodology for the design and evaluation of distillation systems: Exergy analysis,economic features and GHG emissions

This work presents a process design methodology that evaluates the distillation systems based on exergetic, economic, and greenhouse gas (GHG) emission aspects. The aim of the methodology is to determine how these three features should be applied in process design to obtain information about the accuracy of the design alternatives. The methodology is tested and demonstrated on three different energy‐integrated distillation systems: the direct sequence with backward heat‐integration (DQB), fully thermally coupled distillation column (FTCDC), and sloppy distillation system with forward heat‐integration (SQF). The average relative emission saving is the highest for the DQB scheme and this sequence shows the most flexible range of use. The case studies prove the accuracy of our evaluation methodology. On the other hand, it highlights and demonstrates that the exergy analysis can predict the results of the economic study and the environmental evaluation to make the decisions, associated with process design, much simpler. © 2009 American Institute of Chemical Engineers AIChE J, 2010     

无烟末煤气化型焦工艺及经济分析

从设计实践出发 ,论述了无烟末煤气化型焦的生产工艺系统及主要设备 ,初步分析了无烟煤型焦的生产及销售成本 ,认为型焦的合理销售价格无论是对生产企业还是用户都是有利的。     

Analysis of process parameters on the characteristics of liposomes prepared by ethanol injection with a view to process scale-up: Effect of temperature and batch volume

Liposomes have been extensively used as carriers of several compounds, due to their structural versatility in terms of size, composition, surface charge, lamellarity, and facility to incorporate hydrophilic and hydrophobic substances. Among the methodologies for liposomes production, the ethanol injection technique is probably the most suitable for implementation at industrial scale, mainly due to its simplicity. The effects of the aqueous phase temperature and preparation volume on the characteristics of liposomes produced by this technique were evaluated, seeking to attain criteria for its implementation in large scale. The aqueous phase temperature significantly affects the final characteristics of liposomes obtained by this methodology. By varying this parameter, it is possible to control size distribution and polydispersity of the lipid vesicles. Subsequently, process scale-up was carried out using a 10-fold scale ratio. The adapted power per unit of volume (P/V) scale-up criterion showed to be appropriate to reproduce in larger scale the final characteristics of liposomes produced in smaller scale. The results demonstrate that using the ethanol injection technique, it is possible to obtain a relatively narrow distribution of small unilamellar vesicles, appropriately modulating the experimental conditions. Therefore, the preparation of vesicles with the desired diameter and size distribution was essentially fulfilled.