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1.
间硝基氯苯的分离及其可行性研究   总被引:1,自引:0,他引:1  
探讨、分析了对、邻硝基氯苯生产废料中间硝基氯苯的可能分离方法,确定采用恒沸减压精馏法为最佳。通过大量的实验,筛选出了一种合适的恒沸剂,并确定了恒沸减压精馏的最佳工艺条件,同时还对年产200t间硝基氯苯的生产工艺进行了详细的可行性研究,结果表明,该项目投资小、能耗低、收益高,工业化前景广阔。  相似文献   

2.
针对不饱和聚酯树脂生产高浓度废水的特点,采用新型共沸精馏技术进行资源化预处理。实验结果表明,共沸精馏几乎将废水中的原料、聚合中间体等有机物全部浓缩于釜液中,釜底浓缩液COD可高达120万mg/L左右,有机物回收率达93%~96%。将COD约120万nq-g/L的釜液以20%比例投入不饱和聚酯树脂合成反应中,制得了一种新型高性能树脂,且树脂的得率由常规生产的93.4%提高至99.77%。对与共沸剂分离后的COD约为1万mg/L的馏出液采用新型多技术协同催化氧化技术进行预处理,使废水B/C由0.021提高至0.3以上;再采用EGSB+MBBR生化处理和活性炭吸附深度处理,出水可稳定达标排放,并能满足循环冷却水要求。  相似文献   

3.
研究采用间歇精馏法从工业废溶剂油中回收二甲苯和醋酸丁酯,对预处理后的原料进行了间歇精馏工艺实验研究.考察了分离温度、时间和回流比等因素对分离效果的影响.结果表明:在最佳的工艺条件下,二甲苯和醋酸丁酯在馏出液中的含量均达到95%以上,收率分别达到62%和99.4%.基于物料衡算和相对挥发度建立了简捷有效间歇精馏数学模型,模型可较准确预测塔顶馏出物浓度变化.  相似文献   

4.
萃取精馏法分离醋酸-水的研究   总被引:1,自引:0,他引:1  
采用萃取精馏法从醋酸水溶液中分离回收醋酸是一新的研究方向,而适宜溶剂的筛选是研究关键.本实验以高沸点含氮类有机化合物作为醋酸-水萃取精馏的候选溶剂,采用平衡组分分析法对溶剂进行了实验筛选.结果表明,溶剂的引入使体系的相对挥发度有较大程度的提高,其中N-甲基乙酰胺(NMA)使水对醋酸的相对挥发度提高最多,为4.75.因此实验确定NMA为最优溶剂,并进行了醋酸-水萃取精馏的工艺实验.与普通精馏结果对比表明,以NMA为溶剂的萃取精馏法分离醋酸-水的效果非常显著,研究结果对开发环保型的醋酸-水分离新工艺具有重要意义.  相似文献   

5.
采用萃取精馏法从醋酸水溶液中分离回收醋酸是一新的研究方向,而适宜溶剂的筛选是研究关键.本实验以高沸点含氮类有机化合物作为醋酸-水萃取精馏的候选溶剂,采用平衡组分分析法对溶剂进行了实验筛选.结果表明,溶剂的引入使体系的相对挥发度有较大程度的提高,其中N-甲基乙酰胺(NMA)使水对醋酸的相对挥发度提高最多,为4.75.因此实验确定NMA为最优溶剂,并进行了醋酸-水萃取精馏的工艺实验.与普通精馏结果对比表明,以NMA为溶剂的萃取精馏法分离醋酸-水的效果非常显著,研究结果对开发环保型的醋酸-水分离新工艺具有重要意义.  相似文献   

6.
唐海  沙俊鹏  赵翔 《环境工程学报》2014,8(5):1851-1856
用一种具有多孔结构特征的沸石球作为载体固定化硝化细菌强化吸附氨氮废水。结果表明,沸石球能快速固定化硝化细菌,吸附动力学表明150 min对氨氮吸附容量达到2.816 mg/g,而且还有继续增加的趋势。假二级动力学方程和Elovich模型的精确拟合说明,生物沸石球对氨氮的吸附过程可能是非均相扩散起作用及以化学吸附反应为主的复杂转化过程。扩散拟合结果表明,氨氮在生物沸石球的吸附是以液膜扩散和颗粒内扩散为吸附速率的控制步骤,活性的硝化细菌对氨氮的硝化使氨氮在微孔的吸附得到了强化。  相似文献   

7.
探讨了从环己醇/环己酮生产装置产生的酸性有机废水中获取甲酸的方法.在实验基础上,确定了共沸-分馏组合法回收甲酸的工艺过程、适宜挟带剂及工艺条件.采用共沸-分馏组合法处理该有机废水,可获取质量分数为80%以上的甲酸水溶液,甲酸回收率可达70%以上.同时,经本法处理后,该有机废水的COD由1.0×105~1.6×105 mg/L降至5× 102 mg/L以下,COD去除率达98%以上.  相似文献   

8.
电化学方法处理邻硝基氯苯的研究   总被引:3,自引:1,他引:2  
实验研究了电化学对邻硝基氯苯废水的降解作用。对电极材料进行了选择,做了各个电解因素的正交实验,通过HPLC测定邻硝基氯苯含量以及COD含量的测定。结果表明铁阳极的电解效果最好;电解过程中电流是影响邻硝基氯苯降解效果的最主要的因素,其次是pH值;最佳电解条件下邻硝基氯苯的去除率达到100%。另外,对电解机理进行了初步探讨。  相似文献   

9.
杨丽 《污染防治技术》2009,22(4):67-68,119
阐述了治理有机废气的重要性,重点介绍了活性炭吸附-精馏提纯有机废气的回收技术,通过案例分析和对比,显示了该技术的优越性,提出在工业行业中,推广应用活性炭吸附-精馏提纯的回收技术,是符合循环经济理念的,不仅能够减少资源消耗,而且可以降低废气的污染物排放,实现有机废气的资源化利用。  相似文献   

10.
针对某炼化企业在石油储运过程中产生的罐底油泥,进行了油泥样分析和不同萃取剂萃取回收油分实验.经分析该罐底油泥含水率约16.1%,总有机物含量约34.8%,其中可萃取石油类物质约占总有机物成分的67.0%.考察不同溶剂的萃取效果,结果表明,石脑油90 ~ 110℃沸程段的馏分油的萃取效果和工艺可操作性优越于其他常用溶剂,其萃取效果排序为石脑油90~ 110℃沸程段的馏分油>120#溶剂油>正庚烷>石油醚(90 ~ 120℃)>石油醚(60 ~ 90℃);用石脑油90 ~ 110℃沸程段的馏分油在优化萃取工艺条件下,经两次萃取可分离出大于96%的可萃取油分,罐底油泥中有机物的萃出率可达64%以上,比120#溶剂油萃取效果高出约3%~5%,实现了罐底油泥更深程度的萃取和资源化利用.  相似文献   

11.
树脂吸附法处理硝化废水   总被引:1,自引:0,他引:1  
杨旭  俞飞 《污染防治技术》2007,20(3):9-12,78
从14种树脂中筛选出国产大孔吸附树脂AB-8用来处理硝化废水,对硝基苯、硝基氯苯和CODcr,的去除率分别可达70%、99%和43%;用工业乙醇作脱附剂,洗脱效果较好,树脂再生后可重复使用。  相似文献   

12.
The effect of positional isomerism on chemical and photochemical degradations of the Imazamethabenz-methyl (IMBM), a pesticide of the imidazolinone family, has been studied. IMBM is proposed in the form of a mixture of the two positional isomers: meta and para. The development of an effective HPLC method (resolution factor R=1.3) allows us to follow either the abiotic disappearance of the meta and para IMBM and the formation of their breakdown products. The abiotic degradation studies include the chemical hydrolysis, as well as the direct and the indirect photodecomposition. We used TiO(2), a well-known initiator of hydroxyl radicals, to highlight the role of *OH in the indirect photodegradation. This work confirms the different behaviours of positional isomers in the environment. Indeed the chemical or direct photochemical degradation is faster for the meta isomer than for the para. Whereas, concerning IMBM, there is not any prevalent influence of this type of isomerism on the indirect photochemical degradation. The degradation products were tentatively identified by LC-MS, NMR and IR and a degradation pathway was proposed.  相似文献   

13.
The hydrothermal degradation pathways of decabromodiphenyl ether during hydrothermal treatment were investigated. After an initial "Heating time", the reaction runs were carried out at constant temperature (heating to 300 degrees C and keeping temperature) and pressure (8MPa) in a SUS316 stainless steel micro autoclave filled with water. Some decomposition of decabromodiphenyl ether was observed over 200 degrees C, and it was decomposed by more than 99% after 10 min at 300 degrees C. The reactivities of bromine on para and meta substituents were relatively high, while its reactivity on ortho bromine was extremely low. The formations of polybrominated dibenzo-p-dioxins and furans (PBDD/DFs) were observed in the early stages of the reactions at around 300 degrees C. The TCDD toxicity equivalency (TCDD-EQs) of the by-products was determined based on relative potencies (REPs EC(5TCDD)) with the Dioxin-Responsive-Chemical Activated Luciferase gene eXpression (DR-CALUX) bioassays technology. These results indicated that the risk of formation of PBDD/DFs in the hydrothermal degradation of deca-BDE was low, and it would be possible to reduce the TCDD-EQs value by adding some catalyst or alkali, or extending processing time.  相似文献   

14.
针对企业硝基氯苯装置产生的高毒性、难降解的硝基苯类废水,开发出全混态零价铁-芬顿组合预处理工艺,并分别优化了零价铁还原和芬顿氧化的工艺条件。结果表明,pH为2.0、零价铁投加量为220 mg/L时,废水中硝基苯类物质的去除率可达98.5%以上。出水pH约为3.0,继续投加3000 mg/L的H2O2,Fe2+投加比按C(Fe2+,mg/L):C(H2O2,mg/L)=1:10,1 h内COD去除率可达90%以上,且B/C由0.08提高到0.45。可见该组合预处理工艺可大幅削减废水毒性、改善可生化性,且直接运行成本仅为26.28元/吨,具有良好的环境和经济效益。  相似文献   

15.
通过对亚铵法麦草浆黑液性质的研究 ,提出了蒸发浓缩 +生物活性有机肥生产的新技术路线 ,并结合生产实践对该技术加以研究、归纳 ,并进行了经济分析。实践证明 ,运用该技术不仅能实现亚铵法麦草浆黑液的回收和污染治理达标 ,而且能为企业带来可观利润 ,使企业走上可持续发展之路。  相似文献   

16.
Abstract

Enantiomers and racemic mixtures of selected benzilic esters using resolved and raceme permethrinic or chrysanthemic acids of high purity were synthesised via improved methods based on conventional steps. Nine basic structures of selected derivatives having hydrogen, bromo or phenoxy group at meta position were prepared including the well known insecticides of phenothrin, permethrin and cypermethrin. The optical purity of these compounds were determined via an NMR method applying chiral shift reagents. The configuration of the isomers of new a‐cyano‐benzyl esters were assigned via a rule realized by comparing the characteristic 1H NMR shifts of the dimethyl groups attached to the cyclopropane ring.  相似文献   

17.
萃取法预处理间二硝基苯生产废水   总被引:4,自引:0,他引:4  
间二硝基苯生产废水中含有邻硝基苯磺酸和对硝基横酸,采用三辛胺-煤油作萃取剂对其进行萃取处理,在最佳工艺条件下,经过三级萃取,废水的COD去除率达95%以上,硝基物去除率达98%以上,萃取剂用NaOH水溶液处理后可循环使用。  相似文献   

18.
硫化氢吸收净化技术研究进展   总被引:3,自引:1,他引:3  
综合评述了硫化氢气体的吸收净化方法及特点。净化方法分为干法和湿法两大类。大部分干法脱硫剂均不能再生 ,硫容量相对较低 ,主要适于气体精细脱硫。吸收净化工艺能适应较高负荷的脱硫要求 ,应用面广 ,其中尤以吸收氧化法较突出。指出吸收氧化法中的铁基工艺尽管在工艺控制方面还有一定难度 ,但仍可作为一种有较大发展前途的方法。  相似文献   

19.
Estuarine sediments from a USEPA Superfund site in coastal Georgia were extensively contaminated with Aroclor 1268, a mixture of highly chlorinated polychlorinated biphenyls used by a former chlor-alkali plant. Batch slurries of contaminated sediment were incubated for 1 yr with amendments of 2,6-dibromobiphenyl (26-BB) and 2,3,4,5,6-pentachlorobiphenyl (23456-CB) under anaerobic, sulfate-reducing conditions and different pH (5.5-7.5). Organic extracts of slurry sub-samples in a time series were analyzed by congener-specific GC-MS. Dechlorination of 23456-CB was pH dependent and occurred via two routes with the sequential loss of (1) meta and para chlorines and (2) para, ortho, and meta chlorines. Quantitative dehalogenation of 26-BB was observed at all pH. Supplementation of nonachlorobiphenyls (as primers) did not induce dechlorination of native Aroclor 1268 nor of the primers themselves. While contaminated estuarine sediments possess microbial consortia with diverse dehalogenating activities, lack of dechlorination of Aroclor 1268 and spiked nonachlorobiphenyl congeners suggests a bioavailability limitation or enzyme-substrate incompatibilities.  相似文献   

20.
铝业碱性赤泥的悬浮碳化法脱碱工艺研究   总被引:2,自引:0,他引:2  
王琪  李津  赵颖  栾兆坤 《环境工程学报》2009,3(12):2275-2280
研究探讨了碱性废弃物赤泥的常压悬浮碳化法脱碱绿色环保新工艺。详细研究考察了反应温度、反应时间、液固比以及CO2通气量4个因素对赤泥脱碱效能的影响,确定了最佳工艺参数和技术条件。研究表明,在温控60℃,反应时间1.5 h,液固比为10,CO2通气量为0.8 L/min的反应条件下,赤泥脱碱率(以Na2O计)达到85%以上,同时得到含3%~5%碳酸盐的碱性溶液。与传统生石灰脱碱工艺相比,悬浮碳化法具有操作简便、脱碱率高、所得碱纯度高,无废弃物排放等优点,并可实现双废物(CO2废气和赤泥废弃物)的可持续综合利用。  相似文献   

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