高浓含酚炼油碱渣碳化液萃取脱酚的研究 2.连续逆流萃取实验

针对碱渣碳化液突出的酚浓度高问题,选择了30%磷酸三丁酯煤油溶液作为络合萃取脱酚剂。在此基础上,进行了多级连续逆流离心萃取脱酚及萃取剂反萃再生的研究,确定了适宜的工艺操作参数。结果表明,在弱碱性条件下,采用30%磷酸三丁酯煤油溶液处理碳化液,可在不调节温度和pH值的情况下实现高效络合萃取脱酚,脱除率大于99%,且萃取剂易于碱洗反萃再生,有利于工业实施。     

炼油厂高浓度含酚碱渣碳化液萃取脱酚的研究1.脱酚萃取剂的开发

碱渣碳化液最突出的问题之一是酚的脱除。通过对比实验 ,选择了适合于碳化液弱碱性环境的高效、高萃取容量的络合萃取剂 3 0 %TBP煤油溶液。该萃取剂在pH值为 8.5的弱碱性条件下单级萃取脱酚率仍高于99%。     

络合萃取法回收高浓度含酚废水中的酚类化合物 Ⅱ．炼油厂废碱液中酚类的萃取动力学研究

采用恒界面池法,对磷酸三丁酯（TBP）萃取酚的传质动力学进行了研究,并考察了搅拌速率、温度及相界面积对萃取速率的影响。实验结果表明,TBP萃取酚的反应为准一级反应萃取过程,其正向络合萃取反应的表观活化能为4．31kJ／mol,萃取速率受搅拌强度和相界面积的影响较为显著,从实验结果推断其萃取过程为扩散控制模式。     

控制萃取平衡时间选择性分离回收FCC废催化剂酸浸液中的钒

以2-乙基己基膦酸单2-乙基己基酯（P507）为萃取剂,采用控制萃取平衡时间的方法从催化裂化（FCC）废催化剂的含铁酸浸出液中选择性萃取分离回收钒。试验结果表明：采用P507、磷酸三丁酯（TBP）、磺化煤油体积分数分别为10%,5%,85%的协萃体系,在萃取剂皂化率为50%、萃取相比（有机相与水相的体积比）为1∶1、萃取平衡时间为10 min的条件下,经五级逆流萃取,钒的萃取率达99.5%,而铁的萃取率仅为5.2%;在反萃取剂硫酸的质量浓度为150 g/L、反萃取相比为6∶1、反萃取平衡时间为15 min的条件下,经四级逆流反萃取,反萃取液中钒的质量浓度为18 630 mg/L,钒的多级反萃取率达99.5%,反萃取液中铁的质量浓度仅为70 mg/L,实现了钒的有效富集回收。通过控制萃取平衡时间可实现FCC废催化剂硫酸浸出液中钒与铁的有效分离及钒的富集回收。     

用环隙式离心萃取器处理含酚废水的研究

采用环隙式离心萃取器对不同含酚废水及萃取剂体系进行三级萃取试验以及回收萃取剂的反萃取试验。结果表明,酚的萃取率可达９７％,。反萃取率接近１００％,基本达到反萃取完全,而且进行了处理实际工业废水的试验,单级传质级效率约达９１％,三级逆流萃取时酚萃取率约９９％,建立了一个同时计入两相体积变化,传质雍相夹带的多级逆流萃取 计算模型,模型计算值与实测值吻合较好。     

用环隙式离心萃取器处理含酚废水的研究Ⅱ.多级串联实验和计算

采用环隙式离心萃取器,对不同含酚废水及萃取剂体系进行三级萃取试验以及回收萃取剂的反萃取试验。结果表明,酚的萃取率可达９７％ ,反萃取率接近１００％ ,基本达到反萃取完全。而且进行了处理实际工业含酚废水的试验,单级传质级效率约达９１％ ,三级逆流萃取时酚的萃取率约９９％ 。建立了一个同时计入两相体积变化、传质级效率和相夹带的多级逆流萃取过程的计算模型,模型计算值与实测值吻合较好。     

从废脱硝催化剂中回收有价金属钨的研究

用碳酸钠溶液浸出结合季铵盐萃取工艺从失效脱硝催化剂中回收钨。结果表明,在浸出条件为碳酸钠浓度100g/L、液固比2:1、浸出温度180℃、浸出时间3h时,钨的浸出率可达98.5%。浸出液经过由体积分数50%的三辛基甲基氯化铵、20%的仲辛醇和30%的磺化煤油组成的萃取剂溶液萃取、碳酸氢铵溶液进行反萃,可在水相中得到高浓度的钨酸铵溶液,并与溶解在有机相之中的Fe、K等杂质元素进行高效分离。     

从含酚馏分油中萃取酚的溶剂选择及萃取条件研究

目前,对于含酚油中的酚类提取,存在脱酚率低、酸碱用量大,环境污染等问题,针对现有技术的不足,选取合适萃取剂,利用溶剂萃取法提取含酚油中的酚类化合物,以达到绿色化工环保技术的要求。通过筛选有机溶剂,确定以乙醇胺为萃取剂提取含酚馏分油中的酚类化合物。精馏切取含酚油中170~210℃富酚馏分作为萃取原料,进行萃取实验,在充分振荡、充分静置的前提下,得到适宜的萃取条件:萃取温度为室温25℃,萃取剂与原料油质量比为0.4,在此条件下,其单级萃取率可达95%以上。     

直馏柴油芳烃抽提工艺的优化

对模拟直馏柴油芳烃抽提萃取剂进行了筛选，优化了芳烃抽提条件；考察了不同反萃剂、水/溶剂比、反萃剂/溶剂比、精馏塔塔釜温度对溶剂回收过程的影响。结果表明：增大溶剂/原料比对提高萃取选择性和芳烃脱除率均有利；升温会导致选择性下降、芳烃脱除率提高；增大水/溶剂比、反萃剂/溶剂比及精馏塔塔釜温度均有利于提高回收溶剂纯度。在溶剂/原料质量比为3.0、萃取温度为60℃的最优萃取条件下，用3-甲基环丁砜(3-SUL)对实际直馏柴油进行7级逆流萃取，抽余油中芳烃质量分数降至6.6%,芳烃脱除率达到78.2%。在温度为20℃、反萃剂/溶剂质量比为0.5、水/溶剂质量比为0.15的最优反萃取条件下，用环戊烷对溶有萃取物的富溶剂进行3级反萃取，回收溶剂中3-SUL的质量分数为99.01%。     

萃取精馏回收环己烷的双组分溶剂的研究

在研究萃取精馏分离回收环己烷的单溶剂的基础上，研究了双组分溶剂。当剂油比为7:1时，环己醇和四甘醇双组分溶剂可以将正庚烷对环己烷的相对挥发度由单溶剂时的小于1提高到1．11；将2，3—二甲基戊烷对环己烷的相对挥发度由单溶剂时的小于1．07提高到1．21。用该溶剂在小型萃取精馏实验装置上运行，结果表明，环己烷的纯度为98．5％，收率为80％。     

无机碱非水溶液脱除高酸原油中的环烷酸

以NaOH无水乙醇溶液为萃取剂,与高酸原油中的环烷酸进行一级萃取反应。通过界面张力分析和显微镜观察油相水滴分布情况表明,该脱酸方法不会引起油水乳化现象,要求醇的含水质量分数控制在4%以下。结果表明,小型混合澄清槽连续化操作的优化工艺条件为:NaOH用量3 200μg/g,反应温度55℃,反应时间5 min,溶剂/原料油(质量比)0.4,搅拌速率350 r/min。原油经脱酸反应后,酸值(KOH)可降低到0.28 mg/g,脱酸率达到94.2%。     

The Removal of Naphthenic Acids from Beijiang Crude Oil With a Sodium Hydroxide Solution of Ethanol

Abstract

A new method is introduced in this article to separate naphthenic acids from Beijiang highly acidic crude oil with a sodium hydroxide solution of ethanol. The sodium hydroxide solution of ethanol was used as the acid removal reagent by mixing with the crude oil and then allowing the two phases to separate, with the naphthenic acids being extracted from the crude oil. Data indicated that the optimal content of sodium hydroxide in crude oil was 3,000 μg/g and the optimal extraction time was 5 min with the reagent/oil ratio being 0.4:1 (wt/wt). The suitable reaction temperature could be room temperature. The total acid number of the crude oil was lowered from 3.92 to 0.31 mg KOH/g and the acid removal could reach up to 92.1%.     

The influence of leaching parameters on the extraction of vanadium from petroleum coke

The influence of the parameters of the leaching process on the degree of vanadium extraction into the solution from petroleum coke using concentrated (98%) and diluted (10%) sulfuric acids and a hydroxide sodium (12%) as a leaching reagent was studied. Among the measured process parameters were the ratio of solid (coke) and liquid (sulfuric acid) phases, leaching time, acid or alkaline concentration. The process temperature was chosen to be a constant value of 100?°C. The efficiency of vanadium extraction into the solution was estimated by the photometric method and was from 50% to 98%.     

Release of phenolic compounds from cork stoppers and its effect on protein-haze

Cork stoppers contain low molecular weight phenols, mainly as ellagic tannin, whose role in the protein stability of white wine has been not elucidated. The release of cork phenols from cork granules, disks and stoppers of different quality classes (A and D) in synthetic wine was investigated as well as its effect on animal gelatin, lysozyme and wine protein. Amounts of cork phenolic compounds up to 115 and 179 µg/cm² were released within two weeks for best and worst quality cork disks, respectively, indicating the cork quality can strongly affect the phenolic compounds release. Similar trend was found for cork stoppers even if the concentration of phenolic compounds was lower (68 µg/cm²). Protein-haze was observed in presence of both animal gelatin and lysozyme (50 mg/l) when the phenol level exceeded 30 and 9 mg/l, respectively, whereas no effect on wine protein was observed. This research suggests that even if the overall amount of phenolic compounds released from cork stoppers is low, protein-haze can be achieved when the bottle is stored horizontally and motionless due to the high phenols concentration close to the cork stopper.     

低共熔法分离煤焦油中酚类化合物

采用低共熔法萃取煤焦油馏分油中的酚类化合物,考察了萃取剂的种类、萃取温度、萃取时间、剂/酚摩尔比等条件对酚类化合物萃取效率的影响;并以乙酸乙酯为再生萃取剂,考察再生萃取剂循环使用性能。结果表明：以四乙基氯化铵为萃取剂,剂/酚摩尔比为0.4~0.6,在30~40 ℃下萃取30~60 min,其对酚类化合物萃取效率为92.00%~99.99%;GC-MS分析表明,馏分油及其酚类相中酚类化合物主要包括苯酚、单/双/三烷基取代苯酚等;随着馏程温度的升高,馏分油中苯酚和单烷基取代苯酚的含量降低,双烷基和三烷基取代苯酚的含量提高;TEAC萃取剂循环利用3次后,对酚类化合物萃取率下降3百分点。     

Factors governing the removal of mancozeb residues from lettuces with washing solutions

Mancozeb was spiked in smooth and curly lettuces at two different concentrations (low and high), and lettuces were subjected to different washing treatments (with tap water, Amukine, hydrogen peroxide, acetic acid, and ammonium hydroxide) at varying time and temperature. The determination of residual levels was then carried out by using acetonitrile extraction and high performance liquid chromatography with diode array detection (HPLC-DAD). The study of analysis of variance among these experiments allowed identifying the main factors governing the removal of mancozeb residues from lettuces. In general, the oxidant character of the washing agent is the most important condition that affects removal of mancozeb from lettuces, being hydrogen peroxide more efficient than sodium hypochlorite. Moreover, other factors controlling mancozeb removal from lettuces are surface wax, concentration gradient, and also washing pH. The washing processing factor resulted to be a rest of 4% under the optima conditions (either Amukine solution for 10 min at 25 °C, or hydrogen peroxide solution for 5 min at water temperature of 15 °C).     

苄基三甲基碘化铵相转移催化合成N,N-二乙基苯胺的研究

使用苄基三甲基碘化铵作相转移催化剂可在常压下由苯胺和溴乙烷合成 N,N 二乙基苯胺 ,研究了反应时间 ,反应温度 ,催化剂用量 ,反应物摩尔比 ,氢氧化钠溶液浓度 ,氢氧化钠溶液用量等多种反应因素对目的产物产率的影响 ,提出了常压下催化合成目的产物的最佳工艺条件是 :在 50 m L,4 0 %的氢氧化钠溶液中 ,苯胺和溴乙烷的摩尔比为 1∶ 1 .75,苄基三甲碘化铵用量为 0 .75g,6 0℃下常压反应 4 h,产品产率 80 .4 %。