Abstraet--A method for the quantitative determination of vegetable and mineral oils in effluents and sewage sludges is described. The oils are extracted from acidified effluents by liquid-liquid extraction and from acidified dried sewage sludges by Soxhlet extraction using carbon tetrachloride as the solvent. The vegetable oil is transesterified at room temperature and quantitatively estimated by gas-liquid chromatography. After neutralization and separation of the methyl esters of the vegetable oils on a silica gel column, the eluted mineral oils are qualitatively estimated by gas-liquid chromatographic "fingerprinting" analysis and quantitatively estimated by i.r. spectrophotometry.
INTRODUCTION
THE ESTABLISHED analytical methods for oil and petroleum fractions include gas-liquid
chromatography (MORTIMER and LUKE, 1967; EGGERSTEN et al., 1960; ALBERT 1963),paper chromatography (HERD, 1953) and chromatographic fluorescence (SCHULDINER,1951). More recent interest has been focused on the tracing of sources of oil pollution from refineries, rivers, beaches and the sea (COLE, 1968; RAMSDALE and WILKINSON,1968; INSTITUTE OF PETROLEUM STANDARDIZATION COMMITTEE, 1970). The oil content of surface waters (KAWAHARA, 1969; KAWAHARA and BALLINGER, 1970) and of effluents (ADAMS, 1967; LEE and WALDEN, 1970) has also been considered. A previous method developed in the Upper Tame Main Drainage Authority laboratories estimates oil in sewage effluents and sewage sludges by solvent extraction into 40-60°C petroleum ether (JENKINS et al., 1965). A quantitative measure of the oil present is obtained by a reduced pressure evaporation of the petroleum ether solvent and gravimetric assay of the residue. A measure of the vegetable oil content is achieved by saponification of the residue (HILDITCH, 1949). Acidification of the saponification value solution and subsequent extraction with 40-60°C petroleum ether yields the free fatty acids which are converted to their respective methyl esters (MoRRISON &SMITH, 1964) and estimated quantitatively by gas-liquid chromatography (ELLERKERet al., 1968).This approach has been simplified and extended to give a qualitative and quantitative analysis of both mineral and vegetable oils in the effluent and sewage sludges of the Upper Tame Basin.
APPARATUS AND REAGENTS
Reagents
All chemicals should be of analytical grade unless otherwise stated.
Carbon tetrachloride--Spectral grade redistilled.
2-2‘ Dimethoxypropane--Dried over anhydrous sodium sulphate.
Silica gel--60-80 mesh obtainable from Phase Separations Ltd., Queensferry, Flintshire.
Activated in an oven at 105°C for 2 h. Stored in a desiccator.
Methanolic hydrogen chloride--Dry hydrogen chloride gas passed through dry
methanol until the solution is 10 per cent w/w. Stored over anhydrous sodium
sulphate.
Neutralizing mixture--Anhydrous sodium bicarbonate: anhydrous sodium carbonate:
anhydrous sodium sulphate 2:1 : 2 by weight.
Hydrochloric acid--Concentrated solution.
Sodium bicarbonate--0.5 N aqueous solution.
Gas chromatographic apparatus
Lower free fatty acids
Gas chromatograph--A chromatograph with a flame ionization detector is required.
(A Pye 104 is actually used.)
Column--5 ft x ¼ in. o.d. borosilicate glass column containing Chromosorb 101 coated in situ with 2 per cent Carbowax 20 M terephthatic acid in chloroform.
Injection temperature--195°C.
Column temperature--195°C.
Detector temperature--240°C.
Carrier gas--Air free nitrogen. 10 lb in. -2 inlet pressure.
Methyl esters of free fatty acids and methyl esters of vegetable oils
Gas chromatograph--As for free fatty acids above.
Column--5 ft. x ¼ in. o.d. stainless steel column packed with 10 per cent di-ethylene
glycol succinate on JJ‘s "M" phase 72-85 mesh.
Injection temperature--185°C.
Column temperature--185°C.
Detector temperature--220°C.
Carrier gas--Air free nitrogen 30 ml min-
Mineral oils
Gas chromatograph--A temperature programmed chromatograph is required. (A Phillips PV 4000 is actually used.)
Column--2 m x 2 mm i.d. stainless steel coils packed with either: (i) 10~ Apiezon Lgrease on JJ‘s "M" phase 85-100 mesh; (ii) 10~ Silicon elastomer E 301 on JJ‘s
"M" phase 85-100 mesh; or (iii) 2.5 ~ Silicone oil OV17 on JJ‘s "M" phase 85-100
mesh.
Temperature--Temperature programmed 100-300°C at 10°C min-1.
Carrier gas Air free nitrogen 30 ml min- 1.
General apparatus
Infra-red spectrophotometer--An instrument covering the range 2-25/~m with
programmed double beam facilities is required. A Grubb--Parsons Spectromaster II
is actually used.
Silica gel column--A 20 cm x 15 mm i.d. glass column containing 5 g of silica gel.
Sample preparation:
Effluents. Two-and-a-half litres of sample at pH 3-0 is liquid-liquid extracted with 300 ml of carbon tetrachloridefor 4 h in a downward displacement extraction apparatus as shown in FIG. 1. The carbon tetrachloride solution is separated, dried over anhydrous sodium sulphate and distilled to small volume at atmospheric pressure.This residual solution is diluted to a known volume with redistilled carbon tetrachloride,e.g. 10-25 ml.
Sewage sludges. Wet sludge (100 ml) is poured into a tared porcelain evaporating basin. The sludge is made alkaline with 1"0 N caustic soda solution and dried overnight in an oven at 105°C. After weighing, the dried sludge is thoroughly ground with 5 ml of concentrated hydrochloric acid. The ground mixture is then placed in a 541 Whatman filter paper which is in turn transferred to a Whatman 30 × 100 mm cellulose, single thickness, Soxhlet thimble. The solid is extracted in the Soxhlet apparatus for 4 h using carbon tetrachloride as solvent. The carbon tetrachloride solution is recovered, dried over anhydrous sodium sulphate and distilled to a small volume at atmospheric pressure. This residual solution is diluted to a known volume with redistilled carbon tetrachloride, e.g. 10-25 ml.
Preliminary stage
With sewage sludges lower free fatty acids can be determined directly on the aqueous portion of the sludge sample.
An aliquot of the sludge (10 ml) is taken and filtered through a 541 Whatman filter paper. An aliquot (1 t~l) of the aqueous filtrate is withdrawn and submitted for direct aqueous injection gas-liquid chromatography. A quantitative analysis of the lower(C2-C6) free fatty acids is obtained as indicated in FXG. 2.
Stage 1
Higher free fatty acids are estimated by solvent extraction followed by bicarbonate wash and gas-liquid chromatography. The solvent extraction also removes the lower free fatty acids and prevents their interference in Stage 2.
An aliquot of the carbon tetrachloride extract is taken and washed with 2 × 10 ml 0.5 N sodium bicarbonate solution. The alkaline washes are combined and acidified to pH 3.0 with concentrated hydrochloric acid. This aqueous solution is then extracted with 2 × 10 ml carbon tetrachloride. The extracts are combined and 1.0 ml of 2-2‘ dimethoxypropane and 5.0 ml of 10 per cent methanolic hydrogen chloride are added. The reaction mixture is stirred at room temperature for 6 h and then neutralized with 2 g of the neutralizing mixture.
A 5/~I aliquot is used to determine the methyl esters of the higher free fatty acids
by gas-liquid chromatography.
A quantitative analysis of the higher free fatty acids is obtained as indicated in
FIG. 3.
Stage 2
This stage is the transesterification of the vegetable oils and the neutralizing of the reaction product. A modified version of the method of (MAsoN and WALLF.~, 1964) is used for the preparation of the methyl esters of the vegetable oils. This method uses carbon tetrachloride as solvent and does not require elevated temperatures.
摘要：这是一篇关于一种定量测定废水污水中植物矿物油的方法的描述。矿物石油是从酸化的废水中通过液体对液体的方式萃取出来的，而如果研究对象是酸性固体污物的时候，Soxhlet提出了用四氯化碳作溶剂来进行萃取的方法。在室温条件下，矿物油可以进行酯化反应，通过色谱分析法可以对其数量进行估算。再通过中和反应和用二氧化硅胶体分离出矿物油中的甲基酯之后，更加纯净的矿物油可以用气-液”层离法“进行定性估算，定量估算则可以使用“分光光度测量法”
简介：
这个测量方法的建立作用于液体气体的矿物油和小部分石油
色谱分析法（ (MORTIMER and LUKE, 1967; EGGERSTEN et al., 1960; ALBERT 1963）论文 (HERD, 1953)和色谱分析法试剂（SCHULDINER,1951）。最近业界逐渐对从炼油厂，河流，沙滩和海水中 (COLE, 1968; RAMSDALE and WILKINSON,1968; INSTITUTE OF PETROLEUM STANDARDIZATION COMMITTEE, 1970)追踪污染源头产生了兴趣，地表水的石油 (KAWAHARA, 1969; KAWAHARA and BALLINGER, 1970) 也已经经过了很长时间的研究。从前上层控制主要排水的权威实验室曾经发布过一种在核废水和其它污水中在40-60°C提取石油醚的方法。(JENKINS et al., 1965)。一种最近出现的定量测量石油醚的方法则是对其进行减压蒸发，然后测量其残渣的重量(HILDITCH, 1949)。皂化值的酸化解决方案和后来的40-60°C石油醚萃取产出了游离脂肪酸，他们一部分又转变为甲基脂，用气-液色谱分析法可以对其进行定量测定。(ELLERKERet al., 1968)。这个方法简化扩充了对污水废水中的植物矿物油的定性测量。
装置和试剂
试剂：
所有化学试剂必须在使用前做好准备工作，除非有其它规定。
四氯化碳——特殊试剂，再蒸馏
2-2‘二甲氧基——经无水硫酸钠干燥
二氧化硅胶体——60-80目，能够从Phase Separations公司那里得到，地址是昆斯，弗林特郡。烤箱加热105摄氏度以上两小时，储存在干燥器里面。
氯化氢的甲醇溶液——通过干燥甲醇干燥氯化氢气体，直到其浓度为百分之十。储存在无水硫酸钠中
中和剂——无水碳酸氢钠：无水硫酸钠 按重量2:1的比例混合
盐酸——浓溶液
碳酸氢钠溶液——0.5N 溶液
气体层离法仪器
低度游离脂肪酸
气体色层分析器——需要一个火焰离子探测器（经常用Pye 104）
尺寸——5英尺*1/4英寸的包含覆盖着色谱载体的玻璃柱，百分之二的聚乙二醇和氯仿覆盖全体。
注射温度：195摄氏度
柱体温度：195摄氏度
检测器温度：240度
载气：无氧氮气，10磅，2个大气压
游离脂肪酸和植物油的甲酯甲酯
气相色谱仪 ——为了检测上面的游离脂肪酸。
柱体：5英尺 x 1/4英寸的钢柱，内装有百分之十的二-乙烯
72-85的乙二醇琥珀酸酯
注射温度：185摄氏度
柱体温度：185摄氏度
检测器温度：220摄氏度
载气：每分钟30毫升无氧氮气3
矿物油
气体色层分析器——需带有温度控制装置（常常用Phillips PV 4000）
柱体：2厘米x2毫米的钢柱，内置钢圈和弹性硅。
温度：从100摄氏度上升到300摄氏度，10摄氏度每分钟。
载气：每分钟30毫升的无氧氮气
一般装置：
红外光谱仪 ——覆盖范围2-25米，需要一个可编程的双束光。实际操作的时候用的是 A Grubb--Parsons Spectromaster II
二氧化硅柱体：20厘米x15毫米的玻璃柱体，装有5g二氧化硅
样本准备：
污水。2.5份PH值3.0的样品通过液体对液体的方式，在四小时内萃取出了300毫升的四氯化碳，具体方式是用如下所示的仪器向下排出萃取物。将四氯化碳溶液分离，经过无水硫酸钠干燥，并在一个大气压下蒸馏四氯化碳至小体积。剩余的残渣溶液稀释到一个已知的体积，例如10-25毫升
烂泥。湿润的污泥（100毫升）倒入一个配衡瓷蒸发盆。用苏打溶液让其保持碱性和腐蚀性，在烤箱中用105摄氏度干燥一个晚上，称重后，将干燥的污泥用5毫升浓盐酸彻底覆盖，在这之后将混合物至于541Whatman过滤纸上面，此外我们还需要Whatman的30毫米x100毫米的单厚度纤维，Soxhlet 套环。将固体置于四氯化碳混合溶液中，然后用Soxhlet装置进行萃取四个小时。经过无水硫酸钠干燥，并在一个大气压下蒸馏至小体积，四氯化碳溶液会恢复。将剩余的残渣溶液稀释到一个已知的体积，如10-25毫升。
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初步准备
烂泥放在水中，可以直接测量出其中的低级游离脂肪酸。
把能过滤的那些污泥样品（10毫升）取出，然后通过Whatman541过滤纸进行过滤，将过滤好的滤液（1微升）取出备用。含水注射色谱分析法，可以定量的测定下层的物质.(C2-C6)游离脂肪酸得到FXG.2.表示
第一阶段
较高的游离脂肪酸是通过碳酸氢钠溶液洗气之后再用液色谱法进行估计的。该溶液会移除其中的较低的游离脂肪酸，让它们进入实验的第二部分。
过滤出的四氯化碳萃取液用碳酸氢钠溶液（10毫升，浓度为0.5N）进行两次洗操作。碱性洗涤物会被盐酸酸化到PH3.0。.这份溶液用两份每份10毫升的四氯化碳进行萃取。合并萃取液并1.0毫升2-2‘二甲氧基丙烷和5.0毫升10％的氯化氢甲醇溶液分相加。将反应混合物在室温下搅拌6小时，然后用2克中和的混合物中和。
以5微升来等分样品，使用气-液色谱分析法来测定较高的游离脂肪酸。随后会给出定量测定较高游离脂肪酸的方法。
第二阶段
这个阶段是让植物油中的酯基转移，中和产品的酸碱性。有一种改进的方法（MAsoN and WALLF.~, 1964）可以用来准备植物油中需要的甲基酯，