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1.
伯胺N1923络合萃取苯酚   总被引:2,自引:0,他引:2  
以伯胺N1923与磺化煤油、石油醚、甲苯或正辛醇为稀释剂组成络合萃取剂,在25℃下对苯酚模拟废水进行萃取. 结果表明,40%(j) N1923的甲苯溶液萃取苯酚效果最好. 平衡水相pH<8.3时对萃取影响不明显,苯酚以分子形式被伯胺N1923萃取,H+不参与络合反应;无机盐的盐析效应对苯酚萃取影响较大,顺序为(NH4)2SO4>NaCl>NH4Cl. 伯胺N1923与苯酚主要生成1:1型萃合物;该萃取过程放热,升高温度不利于萃取. 反萃后的有机相萃取效果逐渐下降,可能是伯胺溶解造成的. 40%(j) N1923的甲苯溶液错流萃取煤气化废水,挥发酚的一级萃取率超过99.0%,三级错流萃取结果(0.53 mg/L)接近国家污水综合排放标准(0.5 mg/L).  相似文献   

2.
硫酸体系中N235萃取铼的热力学研究   总被引:1,自引:0,他引:1  
以萃取剂N235,稀释剂正庚烷,研究萃取铼的热力学。在N235+(NH4)ReO4+n-C7H16+H2SO4+H2O体系中,温度278.15—298.15 K和离子强度0.1—2.0 mol/kg范围内,以(NH4)2SO4为支持电解质,在H2SO4体系中测定了萃取平衡水相中ReO4-质量摩尔浓度和pH值。计算了萃取反应的标准平衡常数K,并得到经验公式,同时计算了萃取反应的其他热力学量,指出熵和焓都是该萃取过程的推动力。  相似文献   

3.
为回收利用废弃选择性催化还原(SCR)催化剂,采用酸化伯胺N1923从钠化焙烧废SCR催化剂的浸出碱液中萃取分离钨(W),并对萃取参数进行了优化。结果表明,在溶液pH为10、N1923质量分数为10%、水相和有机相的相比为1、时间为4 min和温度为25℃时,W的单级萃取率高达99.28%;溶液中的其他元素P、V和Si的萃取率分别为55.44%、96.70%和55.00%;用硫酸洗涤除去共萃的杂质元素P、V和Si,W的损失可忽略不计,氨水可以从有机相中反萃出96.89%的W得到钨酸铵溶液。利用傅里叶红外光谱仪分析了萃取过程,N1923经H2SO4预酸化后转化为伯胺盐(RNH3+),通过阴离子交换萃取了WO42-。  相似文献   

4.
采用泡沫酸洗塔串循环水洗流程脱除粗氯乙烯中的氯化氢气体,消除了酸性含汞污水对环境的污染,同时使氯乙烯的损失减小到最低限度。针对目前泡沫酸洗塔尚无精确算法的情况,本文提出了对第n块塔板: (T_(n-1)-Tn)CpN_(n-1)+(N_((Hcl)·(n-1))-N_(HCl·n)q_n+(N_(H2)o.n)-TN_(H2)o.n)q_(H2)σ+(T_(n+1)-T_n)(N_(H2)o.n+2.03o(1-W%)/(W%)N_(Hc1))C=O的热平衡——相平衡关系式,采用试差法即可得到泡沫酸洗塔各板上的气液组成和操作温度。  相似文献   

5.
傅焱  张嫡群  杨双革 《化学试剂》2001,23(4):253-253
N-甲基戊胺是合成双膦酸盐类药物埃本膦酸钠的重要中间体 ,美国专利合成采用催化氢化法 (收率 49% )。我们以德科尔 -福斯特 ( Decker-Forster)一级胺烷基化法合成 ,方法简便易行 ,收率好。合成路线如下 :CHO +CH3( CH2 ) 4NH2- H2 OCH =N -CH2 ( CH2 ) 3CH3(CH3) 2 SO4C6 H6CH =N+CH3-CH2 ( CH2 ) 3CH3 .CH3SO3- 2 H2 OCHO+CH3OH+CH3( CH2 ) 4N+ H2 CH3· SO3H-2 Na OHCH3( CH2 ) 4NHCH3+Na SO4+2 H2 O  在 1 L三口瓶中加入 1 0 0 m L无水苯、5 7.8m L( 0 .5 mol)正戊胺和 61 m L( 0 .6mol)苯甲醛 ,加…  相似文献   

6.
The study is focused on the extraction of valuable metals from automotive shredder residue (ASR) by different leaching solutions. First, ASR samples were roasted at 600 °C to simulate a thermal treatment processing. Distil ed water, citric and sulphuric acid were preliminarily investigated, thus two further full factorial systems entailing H2SO4–H2O2 and H2SO4–H2O2–Fe3+ were tested. The preliminary experimental results showed that 0.1 mol·L?1 H2SO4 solution extracted 100%of Cu, Fe and Zn, whereas citric acid leached 100%of Zn and Pb, 59%of Fe and 62%of Cu;whereas, H2SO4–H2O2 and H2SO4–H2O2–Fe3+(Fenton's) leaching media showed that Cu, Fe and Zn can be extracted simultaneously and completely from the ASR ashes before final disposal.  相似文献   

7.
本文对伯胺(N1923)-正辛烷体系负荷铁后进行冷冻蚀刻技术处理.利用透射电子显微镜对萃取前后有机相结构进行观察分析,结合电导率的结果,进一步证实了伯胺负荷铁有机相反向胶团的存在.发现了在萃取过程中以连续相和反向胶团对有机相水含量及电导率的影响规律.  相似文献   

8.
研究了伯胺萃取剂N1923萃取攀枝花钛业公司硫酸法工艺生产工业级TiOSO4液中的钛离子。试验考察了萃取剂浓度、相比、温度、平衡时间、酸值F等因素对钛的萃取率的影响,并测出了钛的萃取等温线。试验结果表明,伯胺萃取剂N1923在工业钛液中具有良好的萃钛性能和钛铁分离性能,Ti(Ⅳ)的萃取率可达98%以上,而Fe(Ⅱ)基本不被萃取。  相似文献   

9.
将环隙式离心萃取器(ACCs)与电喷雾飞行时间质谱(ESI-TOF-MS)相结合,在线监测了回收过程中的钨萃取行为(宏观)和钨形态的转化路径(微观),发现宏观萃取反应和微观离子形态转化同时发生并相互补充。伯胺N1923萃取钨在144 s内即可达到萃取平衡,萃取率高达98%以上,同时,酸钨比n(H)/n(W)是一个关键变量,当酸钨比n(H)/n(W)=2.4时,全流程钨回收率超过93%。最后,得到了基于钨形态监测的萃取机理,同时,减少原料液中W1含量,增加W10含量,可有效提高钨回收效率。  相似文献   

10.
<正> 在燃烧中实际使用的空气量与理论需要的空气量之比称为空气过剩系数,以α表示。若燃料的分子式为C_nH_m,则完全燃烧时其化学反应式为:C_nH_m+(n+m/4)O_2=n CO_2+m/2 H2O每一分子燃料C_nH_m 燃烧时需O_2为(n+m/4)分子,这时N_2为:N_2=79/(21)(n+m/4)式中:21为空气中O_2体积%,  相似文献   

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It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.  相似文献   

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14.
建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。  相似文献   

15.
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

16.
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

17.
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

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以大分子引发剂氯乙酰化聚苯乙烯微球(PS-acyl-Cl)经原子转移自由基聚合(ATRP)法引发丙烯酰胺(AM)和甲基丙烯酸缩水甘油酯(GMA)单体的共聚接枝,制得一种触角状亲水性环氧载体(PS-acyl-g-P(AM-co-GMA)),再经二乙醇胺(DEA)的环氧基开环胺化反应,得到一种含多个-NCH2CH2OH螯合配基的多齿-五元螯合环的触角状亲水性羟胺树脂(PS-acyl-g-P(AM-co-GMA)-DEA)。将此树脂用于硼吸附研究,结果表明,PS-acyl-g-P(AM-co-GMA)-DEA树脂对硼的吸附满足Langmuir方程,为单分子层吸附;饱和吸附量约为37.7 mg·g-1,且树脂5 min即可达到吸附平衡,与其它已报道的吸硼树脂相比,该树脂具有更高的吸附量和吸硼速率。吸附动力学研究表明,树脂吸附硼的过程主要由颗粒扩散过程控制。重复使用5次后该树脂的吸附量基本不变,解吸率均在90%以上,重复使用性能良好。  相似文献   

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