基于电导率测定的地沟油快速检测方法研究

研究用电导法快速鉴别地沟油的方法。测定了几种食用油,地沟油及植物油掺入地沟油等油样的正己烷萃取水相电导率。结果表明相同质量的不同种类的油样电导率大小不同,地沟油的电导率(为47.24μS/cm)远大于其它合格食用油电导率(≤6.0μS/cm)。另外,植物油掺入地沟油的质量分数与电导率具有线性关系(R=0.998)。所以我们可以通过此方法快速有效鉴别油样是否为地沟油以及食用油中是否掺入了地沟油。     

聚苯胺传感器的制作及地沟油快速检测的应用

本研究采用了循环伏安法得到了电流-Na~+浓度图。接着用时间-电流法对地沟油样和花生油样在-0. 15 V电压下测定了电流大小,并且通过查电流-Na~+浓度图得到对应的Na~+浓度大小。结果表明,地沟油一号样、二号样对应钠离子浓度分别为2. 0×10~(-5)g/100 mL和1. 4×10~(-3)g/100 mL;而5次测同样一个花生油样品,对应钠离子浓度大小均低于2. 0×10~(-10)g/100 mL。可以看出初级地沟油和花生油在钠离子浓度上相差几个数量级,所以这种方法能够分辨出地沟油和正常食用油,对快速检测地沟油具有重要意义。     

液相色谱-同位素稀释质谱法检测食用油中辣椒碱类化合物

建立了食用油中辣椒碱类化合物(包括辣椒素、二氢辣椒素、降二氢辣椒素和合成辣椒素)的液相色谱-同位素稀释质谱准确测定方法。样品中的辣椒碱类化合物用碱液提取后,进行自动固相萃取富集净化、同位素稀释质谱法准确定量。4种化合物在两个浓度水平的平均加标回收率为96.2%~105%,相对标准偏差为0.5%~3.8%(n=6),方法检出限均为0.015μg/kg。采用该方法分别对食用油样品和"地沟油"样品中的辣椒碱含量进行检测。结果表明,大多数食用植物油中未检测出辣椒碱,花生油中辣椒碱本底含量在0~1.8μg/kg范围内,多数地沟油中辣椒碱含量600μg/kg,以此可实现正常食用油和地沟油的有效区分,并作为鉴别地沟油的重要手段之一。     

电导率法快速鉴别地沟油的试验研究

通过试验研究用电导率法快速鉴别地沟油,探讨不同操作条件对测定结果的影响。测取不同水油比、震荡时间、温度、油脂种类等因素下萃取水相电导率,选择最佳的操作条件,测量不同种类油品的电导率,半定量分析食用油是否掺伪。结果表明室温条件下,震荡时间30 s,水油比4∶1,静沉15 min时,电导率最大,检测结果最灵敏,地沟油、使用过的食用油、食用油水相电导率分别为67.73~138.87μS/cm、30.54~42.56μS/cm、11.52~19.63μS/cm。如果测定油脂电导率大于45.00μS/cm,可以断定其掺伪。     

地沟油与食用油理化指标的对比分析

根据食用动植物油脂检测的国家标准方法,对比分析了地沟油和食用油的感官指标,碘价、折光率、过氧化值、酸值和电导率等理化指标。结果表明,与食用油相比,地沟油的酸值和电导率明显增大,酸值和电导率可以作为鉴定地沟油的指标。     

地沟油检测技术研究现状

在介绍地沟油分类危害的基础上,分别从地沟油理化指标检测方法、地沟油特征成分检测方法和地沟油检测仪器设备三个方面综述了地沟油检测技术的研究现状,指出快速、准确、易操作是地沟油检测所面临的问题,食用油的内源性普遍性指标或成为地沟油快速准确检测的理想指标。     

餐厨垃圾资源化利用与生物柴油对接

<正>近来,关于地沟油回炼进入餐桌的报道引起国人震惊,使地沟油、食用油和生物柴油这3个敏感词真实地摆在公众面前。地沟油等餐厨废弃油脂本是生物柴油起步的基石,至今仍是国内生物柴油生产企业的主要原料。随着国家对地沟油的危害     

地沟油中盐分的检测及脱除方法探讨

采用ICP-MS方法对地沟油试样进行了检测,结果表明,其中铬、铅、铁、铜、钠等金属含量均远高于食用油正常标准范围。还采用活性炭、凹凸棒土作为吸附剂,炼油企业的原油脱盐剂对地沟油中的金属元素的脱除进行了探讨研究,实验结果表明,这三种物质均能达到理想的脱盐效果,但若选择性脱除地沟油中的金属含量时需优化操作温度及试剂用量比以取得更好的效果。     

江苏洁美公司“地沟油”炼成生物柴油

位于丹阳市的江苏洁美生物能源有限公司采用华东理工大学的关键技术，所有原料全部是“地沟油”、废弃食用油等“差油”，生产出淡黄色、带脂香的生物柴油。江苏洁美公司用“地沟油”炼成的生物柴经检测达到欧盟标准，可完全取代0号柴油。     

油中反式脂肪酸含量与地沟油检测方法初探

对市场上6种食用油的反式脂肪酸含量进行了测定。检测结果,6种食用油总反式脂肪酸的平均含量为:橄榄油(0.19%)、茶籽油(1.01%)、花生油(1.09%)、葵花籽油(1.23%)、大豆油(1.32%),玉米油(2.04%)。用本方法测定劣质油中的反式脂肪酸,以期探索检测地沟油的方法。     

酶促泔水油生产生物柴油条件的研究

以泔水油资源转化为宗旨,利用中性脂肪酶催化泔水油与甲醇反应制备生物柴油。通过50g泔水油正交实验获得最佳转酯化反应条件：油醇摩尔比1∶3,油酶质量比1∶1,温度45℃,油溶剂质量比1∶0.6,反应时间10h后,生物柴油产率可达89.7%以上。对生物柴油密度、黏度、馏程、凝固点、硫含量、残碳、十六烷值等多项指标进行检测,油品的质量符合我国生物柴油的标准。在优化条件的基础上进行10L和50L反应釜实验,10h生物柴油的产率达到80%以上。     

合成气压缩机(103-J)高压缸污油收集器漏油原因分析及对策

通过对合成气压缩机(103-J)高压缸污油收集器漏油进行分析计算，找出了产生漏油的原因，并制定出相应的处理措施。     

大机组油路的清洗

我国各大化肥装置的大机组油路或多或少存在着油路不净、流通不畅而严重威胁装置安全运行的事例。本文着重介绍了合成氨装置大机组公用油系统油路的清洗方法、步骤及效果等问题,以供借鉴。     

Scalable synthesis of oleoyl ethanolamide by chemical amidation in a mixed solvent

Oleoyl ethanolamide is a lipid mediator that exhibits biological activity in animal and cell models. In this study, an effective process is described to synthesize oleoyl ethanolamide by chemical amidation with native oil used as an acyl donor in the presence of sodium methoxide. Reaction conditions were optimized. When the amidation reaction was conducted in a mixed solvent, by reacting 2 mmol high oleic sunflower oil and 20 mmol ethanolamine in the presence of 1.5 % sodium methoxide with agitation, >90 % fatty acid ethanolamide was formed after 3 h of reaction time. The fatty acid ethanolamide product was purified by a two‐step crystallization process to prepare oleoyl ethanolamide. Highly pure oleoyl ethanolamide was obtained in a 70.3 % molar yield. The novelty of the work is the use of native oil as acyl donor and the mixed solvent used as the reaction media. The use of native oil avoids the formation of ion pairs with ethanolamine that can occur in other synthesis routes.     

原油稳定装置污染源分析与控制

文章通过对西部某采油厂原油稳定装置污水、大气、噪音和废弃垃圾污染的种类，分析了其主要来源，提出了如何控制、减少污染物的建议。     

Enhanced oil recovery using carboxylate surfactant systems

Oil displacement tests in water wet Berea sandstone cores containing residual crude oil flooded with water have shown that high tertiary oil recoveries can be obtained using the sodium salts of readily available carboxylic acids. Using a 10% pore volume surfactant slug containing 3.0% sodium isostearate and 3.0% isopentyl alcohol followed by a polyacrylamide mobility buffer resulted in a 92% tertiary oil recovery, which compares well with recoveries using petroleum solfonates. Oil recoveries were highly dependent on pH and added base. Aliphatic C18 carboxylates gave higher recoveries at lower pH using sodium bicarbonate as the added base (pH 8.5) rather than sodium hydroxide, sodium carbonate or sodium orthosilicate (pH 11–13). In contrast, aromatic carboxylates e.g., sodium p-(1-pentylnonyl)benzoate, gave higher recoveries at higher pH using sodium carbonate rather than sodium bicarbonate. Carboxylates with branched alkyl groups, e.g., isostearate, gave higher tertiary oil recoveries than unbranched carboxylates, e.g., oleate or stearate. Low cost tall oils and tall-oil fatty acids, when neutralized with base, gave oil recoveries of 60–80%. Carboxylates were found to give good oil recoveries even when significant amounts of calcium ion were present.     

生物净化处理含油循环冷却水的试验研究

针对炼油厂被泄漏的油品污染的循环冷却水系统的情况,采用了油污清洗剥离、生物降解净化、水质稳定、旁滤降浊的非置换组合处理工艺方案,静态、动态模拟试验表明:该处理方案具有除油效果好、阻垢缓蚀性能良好、不排污置换、系统平稳、环保等特点.     

A motor oil soil for detergency testing

Bright Stock/Pale Oil (BS/PO) soil represents a typical motor oil soil, but it is more constant in composition than clean or dirty commercial motor oil. It does not require the addition of any dye, as is the case with mineral oil or cooking oil, and when applied to cloth, it produces very uniform soilings. The statistical reproducibility of detergency tests run with BS/PO is better than mineral oil and about as good as sebum.     

Continuous removal of metallic ions from soybean oil

Removal of metallic ions like copper, nickel and sodium from vegetable oils is important to edible oil processors. Continuous washing of soybean oil with acidic water, followed by ion exchange treatment of the aqueous solution to remove metallic cations and permit reuse of the water, is an effective and economical method for metal removal. Several types of washing apparatus were studied: A Podbielniak countercurrent centrifugal contactor, a rotating disc countercurrent contactor and a contactor-centrifuge system. Equipment for the third system is already available for the continuous washing of refined oil in modern refineries. With a contactor-centrifuge ion-exchange system, copper in soybean oil was reduced by washing from 1.5 to 0.03 ppm; nickel, from 0.4 to 0.04 ppm; sodium, from 20 to <1 ppm. The effects of pH and type of acid (anion) were studied. The cost of washing soybean oil by this method is estimated to be about 0.06 cent/lb, and there is no loss of oil. One of 28 papers presented at the Symposium, “Metal-Catalyzed Lipid Oxidation,” ISF-AOCS World Congress, Chicago, September 1970. No. Utiliz. Res. Dev. Div., ARS, USDA.