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51.
外消旋苯丙氨酸的配位萃取拆分 总被引:2,自引:1,他引:2
以苯丙氨酸为研究对象,应用手性溶剂萃取拆分技术,考察了在含有配位金属离子和N-n-烷基化氨基酸的两相系统系统中被折拆分后苯丙氨丙氨酸对映体的分配行为。着重研究了在有机溶剂及水相中萃丙氨酸的初始浓度、萃取温度、配位金属离子等对萃取拆分效果的影响,结果显示,温度和浓度对萃取拆分的影响不大,而有机溶剂和配位离子对萃取拆分效果的影响较大。 相似文献
52.
催化氧化H2S生产不溶性硫磺的新工艺研究 总被引:2,自引:0,他引:2
首次提出以H2S为原料,NOx O2催化氧化H2S制备不溶性硫磺的新工艺,分析了该工艺的反应原理、工艺流程和不溶性硫的稳定性原理,并对该催化氧化的工艺条件和浸取荆的选取进行了实验,得出最佳工艺条件:催化氧化荆HNO3、FeCl3浓度分别为15%~20%、8%;催化氧化反应温度为30~40℃;使用三种低毒混合溶剂为浸取荆,其沸点为80~90℃、有不易燃烧的优良特性。 相似文献
53.
从银杏(Ginkgo biloba)叶提取物的微生物转化试验中,获得1株能够转化银杏叶提取物组分,编号为YM34161的微生物菌株.通过对该菌的形态特征观察及ITS(internal transcribed spacer)序列分析,确定该菌株为小刺青霉的1个新变种,命名为小刺青霉云南变种(Penicillium spinulosum var.yunnanensis n.var.Xing etCben).同时对菌株YM34161转化银杏叶提取物组分前后变化进行了TLC对比. 相似文献
54.
用萃取第三相形成法处理1-萘胺-8-磺酸生产废水 总被引:2,自引:0,他引:2
用萃取第三相形成法,以N_(235)为萃取剂,煤油为稀释剂处理化学需氧量(COD)初始值高达50g/L以上的1-萘胺-8-磺酸生产废水。在萃取剂的浓度 为0.20,相比1:1,萃取时间10min和室温条件下,二级错流萃取的COD去除率可达到97%。 相似文献
55.
In the present work, we showed a novel method to synthesize cyano-functionalized multiwalled carbon nanotubes (MWCNTs-CN) and utilize it as a solid-phase extraction sorbent for preconcentration of phenolic compounds in environmental water samples. MWCNTs-CN was synthesized through surface functionalization of multiwalled carbon nanotubes (MWCNTs). The functional groups on the surface of modified MWCNTs were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy. The analytical procedure was based on a conventional solid-phase extraction step for which 100 mg of MWCNTs-CN were packed in a 3 mL polypropylene cartridge. Analytes were thus isolated and preconcentrated from the pretreated samples and subsequently detected on high-performance liquid chromatography-ultraviolet detection. The results showed the proposed method exhibited good sensitivity and precision for the extraction and elution of analytes. The limit of detections (S/N = 3) of the method were 0.45, 0.09, 0.08, and 3.00 ng mL(-1) for p-chlorophenol, 1-naphthol, 2-naphthol, and 2,4-dichlorophenol, respectively. The mean relative recoveries (n = 3) were between 80.28 and 103.13%, and the repeatability (RSD ≤ 5.10%) and reproducibility (RSD ≤ 7.68%) were accepted. This developed method was applied to determine phenolic compounds in environmental water samples. There is a positive result only for 2-naphthol with concentration of 0.38 ng mL(-1) in seawater sample. 相似文献
56.
Solvent extraction of some selected metals from an aqueous buffered solution by LIX26 extractant has been studied. The pH1/2 values (at which 50% of metal ion is extracted) for extracting different metals by 1 v/v% LIX26 extractant in methyl isobutyl
ketone have been obtained. The order of extraction of metals by LIX26 extractant as a function of pH1/2 value is Pd(II)<Cu(II)<Sb(III)<Fe(II)<Co(II)<Zn(II)<Ni(II) <Pb(II)<Mn(II)<Cd(II). 相似文献
57.
废FCC催化剂(废石油催化炼化催化剂)中含有2%以上的富La或富Ce稀土,用盐酸浸取后可得到含有稀土元素和非稀土杂质的氯化稀土溶液。研究用P507(2-乙基己基膦酸单-2-乙基己基酯,HEH/EHP)从盐酸介质中萃取稀土的工艺方法,考察萃取分离稀土的主要影响因素。试验结果表明:可以从P507-煤油-盐酸体系中有效地萃取出稀土元素,较好地实现稀土元素和非稀土杂质的分离,其较优工艺条件为:萃取剂浓度(P507体积分数)为60%,浸取液pH为2.5,萃取相比为2:1,萃取平衡时间为30 min;负载有机相直接用盐酸进行反萃得到氯化稀土溶液,反萃盐酸浓度为2.0 mol/L,反萃平衡时间为60 min。该方法工艺简单,解决了废FCC催化剂的处理问题,减少对环境的污染,同时也回收稀土金属。 相似文献
58.
Investigation of aggregation in solvent extraction of lanthanides by acidic extractants (organo-phosphorus and naphthenic acid) 总被引:3,自引:0,他引:3
Three acidic extractants (Ⅰ) di(2-ethylhexyl) phosphoric acid (HDEHP),(Ⅱ) 2-ethylhexyl phos-phonic acid mono-2-ethylhexyl ester (KEHPEHE) and (Ⅲ) naphthenic acid were employed in preparing the samples for the characterization of the coordination structure of lanthanlde-extractant complexes and the physicochemical nature of aggregates formed in the organic diluent of the solvent extraction systems.Photo correlation spectroscopy (PCS) re-suits on the aggregates formed by the partially saponified HDEHP in n -heptane showed that the hydrodynamic radius of the aggregates was comparable to the molecular dimensions of HDEHP.The addition of 2-octanol into the diluent,by which the mixed solvent was formed,increased the dimensions of the corresponding aggregates.Aggregates formed from the ianthamde ions and HDEHP in the organic phase of the extraction systems were found very unstable.In the case of naphthenic acid,PCS data showed the formation of w/o microemulsion from the saponified naphthenic acid in the mix 相似文献
59.
董学畅 《云南民族大学学报(自然科学版)》2001,10(1):276-278
通过质谱分析法和理论计算首次对新螯合萃取剂4,4'-十二烷二酰基双PMP的质谱特性进行了较系统的研究与报道,并对其基峰、主要碎片离子形成的机制和规律进行了研讨. 相似文献
60.
Didier Villemin Bernard Moreau Abdelghani Elbilali Mohamed-Amine Didi M’hamed Kaid Paul-Alain Jaffrès 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2511-2519
The reaction of polyamines with phosphorous acid and formaldehyde in water under focused microwave irradiation provides a facile and rapid synthesis of poly(aminomethylenephosphonic) acids. 相似文献