Removal of pesticides from wool wax by continuous countercurrent dual-solvent extraction

Pesticide residues in raw wool wax were removed to below detectable levels by continuous countercurrent extraction with hexane and N,N-dimethylformamide (DMF) in a pilot-scale mixer-settler contactor. The disengagement of the phases in the settling compartments was promoted by the addition of a small amount of formic acid (3% vol/vol) to the DMF-rich feed. Empirical equations were developed to predict the effect on the pesticide partition coefficients of the wool wax concentration, the presence of small amounts of water, ethanol, and/or isopropanol in the solvents, and the temperature used in the contactor. These empirical equations were included in equations that describe the concentration of the pesticides in the different stages of the contactor and were used to develop a spreadsheet model that accurately predicted the mixer-settler’s performance. The raffinate wool wax produced by this process after conventional neutralization met all BP and USP specifications for pharmaceutical lanolin.     

加速溶剂萃取技术(ASE)在农药残留分析中的应用

加速溶剂萃取（ASE）是采用常规溶剂，在较高的温度（50℃-200℃）和压力（1000-3000psi或10.3—20，6MPa）下对固体或半固体样品进行萃取的新颖的样品前处理技术，具有操作简便、省时省溶剂、减少有机溶剂对环境的污染、萃取操作自动化的特点。介绍了ASE的原理、仪器操作和影响因素，并概述了ASE在土壤、蔬菜、水果及生物样品残留农药提取中的应用，提取的农药种类有有机氯、有机磷和多种除草荆。特别是在多残留检测中，加速溶剂萃取技术更易于同时提取不同类别的多种农药，简化净化过程，并在快速检测方面发挥重要作用。加速溶剂萃取的提取效率和索氏提取相当。     

Recovery of vanadium from ash-leaching solutions by solvent extraction

One of the principal problems during vanadium recovery from combustion residues is its purification, mainly from iron and nickel. This can be achieved by selective solvent extraction of V from liquors obtained by ash-leaching. The use of solvents also makes feasible the recovery of V from boiler washing water and leaching ponds. In the present work, leach liquors from two fouling-ashes were extracted at various pH levels with secondary, tertiary and quaternary amines, with di-(2-ethylhexyl) phosphoric acid (DEHPA), and with DEHPA-tributylphosphate mixtures. Various concentrations of the solvents in kerosene were used. Both DEHPA and amines (secondary and tertiary) are good and selective extractants for V leached from ash. However, amines always require V oxidation and partial neutralization of the leach liquors; DEHPA seems more interesting because it does not need any preliminary V reduction nor partial neutralization, provided that ash leaching is carried out with water and not with acid.     

Characterization of supercritical fluid extracts from raw wool by TLC-FID and GC-MS

Extraction selectivity of whole wool wax from raw wool by using ethanol-modified carbon dioxide at constant pressure (100 bar) and temperature (60°C) was studied. A kinetic study was carried out to optimize the percentage of ethanol and the extraction time. The modified carbon dioxide was decompressed in ethanol as a collection solvent, leading to the formation of two different fractions as a function of their solubility. Qualitative and quantitative analyses of the lipid classes present in the collected fractions were performed by TLC coupled to an automated FID system (TLC-FID). Moreover, a detailed structural comparison was carried out between the aliphatic high-molecular-mass esters and the steryl ester patterns by means of subambient pressure GC-MS in both the EI and the ammonia positive Cl modes. Considerable differences in the lipid composition of the two wool wax fractions collected were observed by TLC-FID and GC-MS.     

Prepress solvent extraction of cuphea seed

Simulation of commercial processing of Cuphea seed to obtain needed quantities of oil and meal was accomplished with pilot facilities. Cuphea seed was conditioned in a single-deck cooker. Cooked seed was pressed with a mechanical screw with two-speed shaft, variable-speed drives and a four-section cage with cored sleeves. A feed rate of 22 kg seed/h and a feed screw-to-main shaft ratio of 2:1 gave good press cake with 8.1% residual oil. Press cake was extracted in a batch-type modular extraction pilot plant. Miscella stages were sequentially pumped through the beds, followed by hexane rinses. Spent cake was desolventized and toasted, and full miscellas were stripped to recover the crude oil. The finished Cuphea meal had only 0.30–0.55% residual oil. Thus, conditioned Cuphea seed was easily pressed without prior flaking to acceptable cakes, and conditions simulating commercial solvent extraction efficiently removed residual cake oil.     

邻仲丁基苯酚萃取回收废水中二甲基甲酰胺

采用高沸点萃取剂邻仲丁基苯酚萃取回收废水中的二甲基甲酰胺。对质量浓度为100 g/L的模拟废水,在25℃下以邻仲丁基苯酚为萃取剂时分配系数可达6.92,远高于低沸点溶剂氯仿萃取时的分配系数0.91。在相比1∶1(体积比),单级萃取时,萃取率即高达87.54%。3级萃取时,废水中N,N-二甲基甲酰胺(DMF)质量浓度从100 g/L降低至2.44 g/L。在邻仲丁基苯酚中加入稀释剂可改善澄清分层速度。     

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%。     

Characterization of the extracts and residues from CS2-N-methyl-2-pyrrolidinone mixed solvent extraction

The extracts and residues obtained by extraction of five bituminous coals with CS₂-N-methyl-2-pyrrolidinone mixed solvent (1:1 by volume) were characterized at room temperature. The extraction yields were 31.1–63.0% (daf) and the extracts were fractionated into acetone soluble (AS), acetone insoluble-pyridine soluble (PS) and pyridine insoluble-mixed solvent soluble (MS) fractions. The MS fraction, which was the heaviest fraction examined, had higher values of % oxygen, f_a, molecular weight and spin concentration than the corresponding AS and PS fractions, but a similar degree of aromatic condensation. The quantities of volatile matter (daf) in the residues were similar or slightly less than those in the extracts.     

Microscale recovery of total lipids from fish tissue by accelerated solvent extraction

A number of techniques are available for the extraction of lipids from a variety of tissues; however, conventional methods are characteristically labor intensive, typically involve large volumes of toxic solvents, and usually require at least 1 g of tissue. With the availability of accelerated solvent extraction (ASE) technology, the opportunity exists to modify classical lipid extraction techniques such that automated high-pressure, high-temperature extractions may be performed with the use of far smaller volumes of costly and harmsul solvents. Moreover, the high extraction efficiency attainable by ASE suggests that significantly less tissue would be required than is routinely used. This paper describes the adaptation of previously developed lipid extraction solvent systems for use with ASE toward the purpose of extracting total lipids from 100 mg of fish tissue. The efficacy of three solvent systems for lipid extraction from representative fish tissues, including a standard reference material, was explored using gravimetry and FA analysis by GC. A TG was used as a surrogate to monitor overall method performance. The findings herein demonstrate that microscale ASE represents an effective and efficient alternative to traditional lipid extraction techniques based on quantity and composition of extracted lipid, surrogate recovery, and precision.     

三辛胺-异戊醇有机溶剂萃取制备磷酸二氢钾

以工业湿法磷酸和氯化钾为原料,开展溶剂萃取法制备磷酸二氢钾的研究。通过筛选确定采用三辛胺-异戊醇作有机萃取剂,考察了有机相与水相比、反应时间、反应温度及循环次数等因素对萃取法制备磷酸二氢钾的影响。实验结果表明,在三辛胺-异戊醇按体积比为1∶1制成混合萃取剂、反应温度为20 ℃、萃取时间为60 min的最优条件下,磷酸二氢钾产品的回收率≥95%,产品纯度≥98%。该方法具有产品纯度高,萃取温度低、操作简单等优点。     

溶剂萃取法从化学镀铜废液中回收铜

采用溶剂萃取法研究了从含强络合剂的化学镀铜废液中回收铜的可行性，结果表明：从含酒石酸钾钠的化学镀铜废液萃取铜时，采用LIX54萃取剂，在pH值为6－10之间，铜的萃取率大于99％，然后通过反萃，可以得到能回用于化学镀铜生产线的硫酸铜溶液。     

Biodegradation of slop wax by Bacillus species isolated from chronic crude oil contaminated soils

Slop wax waste by-product obtained through the lube oil manufacture was subjected to biotreatment using five isolated Bacillus species at 30 °C and various incubation periods, 7, 14 and 21 days. The results obtained from HPLC for the 15 samples showed that the aromatic contents decreased, especially, for that treated with Bacillus sp. MAM-27 which degrade PAHs faster at 1% (w/v) concentration of slop wax waste by-product and exhibited high biodegradation ability within 1 week. Bacillus sp. MAM-27 degraded 99.9% of PAHs, while Bacillus sp. MAM-24 degrades 99.8% of PAHs within 2 weeks and then the degradation ability is slightly increased afterwards. The gas chromatographic analysis of the samples before and after treatment with Bacillus spp. showed that, the aromatics, naphthenes and iso-alkanes were more degradable than saturated n-paraffins. Treatment by Bacillus sp. MAM-27 and Bacillus sp. MAM-24 can be an effective method for biodegradation of slop wax waste by-product leading to paraffin waxes match with plastic paraffin wax according to USSR 1121284 specifications.     

压力对溶剂法脱除焦油沥青中固体颗粒物的影响

精制沥青是制备各种功能炭材料的前体,焦油沥青需要预处理脱除其中的固体颗粒物（称为喹啉不溶物,QI）以得到精制沥青,压力是脱除QI的重要条件。本文以煤焦油沥青和添加生物质沥青的混合沥青为原料,研究压力对溶剂法脱除固体颗粒物的影响,测试不同压力下精制沥青的QI含量及产率,利用纳米粒度分析仪、扫描电子显微镜和高温黏度测定仪对QI颗粒形貌、粒度及脱除体系黏度进行表征和测定,分析压力对固体颗粒物絮凝沉降的影响规律。研究结果表明,增加压力对沥青收率升高有明显影响,使精制煤焦油沥青的收率由常压的64.6%（质量分数）提升至1MPa时的84.3%（质量分数）,精制沥青的QI含量维持在0.06%~0.1%（质量分数）之间。添加15%生物质沥青的混合沥青,产率则由常压时的55.7%（质量分数）提升至1MPa时的72.5%（质量分数）。压力对精制沥青的QI含量影响较小,压力增大,溶剂对沥青组分尤其是重质组分的溶解能力增强,使精制沥青产率升高。较高压力也使体系的黏度略微增大,造成部分QI颗粒沉降困难,不过影响较小。中间相沥青制备的结果表明,精制沥青可以制备出具有流域型结构的中间相沥青,添加生物质沥青更好地改进了流域型的显微结构。     

介质液液萃取-高效液相色谱法快速测定蜜桃汁中的多菌灵农药残留

建立了一种以支撑介质液液萃取．高效液相色谱法为基础,快速经济测定果汁中多菌灵农药残留的分析方法。以经过特殊工艺处理的硅藻土为介质液液萃取的吸附填料,对苯并咪唑类农药中有代表性的多菌灵样品进行前处理,结合高效液相色谱法进行分析检测。在优化液相检测条件和萃取条件的同时,从添加回收率、精密度、方法定量限等方面对该方法进行了评价与验证。结果表明,使用介质液液萃取的方法萃取蜜桃汁样品中的多菌灵,添加回收率的平均值在94％以上,方法最低检出限为0．014μg/mL,方法定量限为0．04μg／mL。方法具有前处理简单、分析速度快、经济、重复性好、分析时间短等优点,可推广于其它果汁中多菌灵农药残留的检测。     

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.     

Recovery of eicosapentaenoic acid from fungal mycelia by solvent extraction

Utilization of lipids containing eicosapentaenoic acid (EPA) produced by microorganisms requires processes for their efficient recovery from microbial cells. Recovery of EPA from mycelia of the fungusPythium irregulare by solvent extraction with hexane-isopropanol (HIP) in a pilot-plant colloid mill was investigated. Extraction efficiencies of 96% for lipid and EPA were achieved with a 3∶2 (vol/vol) HIP mixture by milling wet, filtered mycelia for 5 min at a solvent/dry solids ratio of 100 L/kg. The process yielded a crude extract that contained up to 96% lipid and an EPA content as high as 24% (with no selectivity for EPA).     

Selective removal of iron(III) from highly salted chloride acidic solutions by solvent extraction using di(2-ethylhexyl) phosphate

Metal ions including Fe³⁺, Ca²⁺, Mg²⁺, Ni²⁺, Co²⁺ and Cu²⁺ are commonly found in the leaching solution of laterite-nickel ores, and the pre-removal of Fe³⁺ is extremely important for the recovery of nickel and cobalt. Di(2-ethylhexyl)phosphate acid (D2EHPA) showed high extraction rate and selectivity of Fe³⁺ over other metal ions. The acidity of the aqueous solution is crucial to the extraction of Fe³⁺, and the stoichiometry ratio between Fe³⁺ and the extractant is 0.86:1.54. The enthalpy for the extraction of Fe³⁺ using D2EHPA was 19.50 kJ/mol. The extraction of Fe³⁺ was ≥99% under the optimized conditions after a three-stage solvent extraction process. The iron stripping effects of different reagents showed an order of H₂C₂O₄>NH₄HCO₃>HCl>NaCl>NaHCO₃>Na₂SO₃. The stripping of Fe was ≥99% under the optimized conditions using H₂C₂O₄ as a stripping reagent.     

萃取法分离钛白废酸中的铁

首先通过臭氧氧化作用把钛白废酸中的二价铁转化成三价铁,然后采用萃取法去除其中的三价铁。考察了络合剂（盐酸）浓度、萃取剂、萃取相比等对三价铁萃取率的影响,并初步探索了反萃法回收萃取剂及萃取剂的循环利用。结果表明：当盐酸浓度为3.4 mol/L时,几乎可完全络合溶液中的三价铁;在萃取剂磷酸三丁酯中加入苯作为稀释剂,可有效降低磷酸三丁酯的粘度,消除萃取过程中的乳化现象;磷酸三丁酯萃取三价铁的传质过程很快,2-3 min即达平衡;当萃取相比O/W（萃取剂与钛白废酸体积之比）=0.6∶1时,三价铁萃取率可达97%以上。当反萃相比W/O=4∶1时,三价铁反萃率接近100%。磷酸三丁酯经过5次萃取-反萃循环后,三价铁的萃取率没有明显下降。去除三价铁后的钛白废酸,经蒸馏浓缩到质量分数70%左右,再与浓硫酸混合后可用于钛白粉的生产,蒸馏过程中回收的盐酸循环使用。反萃出来的三价铁可作为生产铁红的原料。     

双液相萃取棉籽油制备脂肪酸甲酯

以双液相萃取技术处理棉籽,在得到脱毒棉粕的同时得到含有高质量毛油的非极性相。以非极性相作为与甲醇进行酯交换反应的原料,得到脂肪酸甲酯和甘油。考察了非极性相溶剂石油醚与棉籽油的比例对酯交换转化率和洗涤粗产品用水量的影响,确定了石油醚与棉籽油的最佳质量比为3,在此条件下,洗涤用水量可降低一半。考察了醇油比、催化剂用量、反应温度、反应时间等参数对转化率的影响。应用正交实验的方法找出酯交换反应的适宜条件为：醇油比6：1,催化剂用量1.1％,反应温度60℃,反应时间120min。在此反应条件下,产物中脂肪酸甲酯的含量可达97.4％。