共查询到18条相似文献,搜索用时 125 毫秒
1.
高纯,超细SrTiO3中钛锶比的测定 总被引:3,自引:0,他引:3
将化学沉淀法制备的SrTiO3溶于硫酸,加入有H2O2存在的40%乙醇溶液中,加入过量EDTA标准溶液,TiO^2+形成Ti-H2O2-EDTA络合物,Sr^2+沉淀为SrSO4。钛、锶分离后,用重法测定锶的含量,用Cu^2+离子标准溶液回滴过量EDTA,测定钛的含量。 相似文献
2.
用NH4SCN、(C4H9)2N^+Cl^-为释放剂,选择性螯合滴定法测定镀铬溶液中的铁。EDTA螯合Fe^3+和其他阳离子,然后加入NH4SCN和(C4H9)N^+Cl^-分解Fe-ED-TA螯合物、释放出的EDTA,用In(NO3)3标准溶液返滴定。实验表明,各种常见阳离子都不干扰测定铁。该法已成功地用于测定镀铬溶液中的铁含量。 相似文献
3.
饲料级硫酸锰测定方法研究 总被引:1,自引:0,他引:1
钟国清 《四川化工与腐蚀控制》2000,3(6):6-8
本文报道了在pH=5.4缓冲溶液中,以EDTA-Cu及1-(2-吡啶偶氮)-2-萘酚(PAN)混合液作指示剂,EDTA标准溶液滴定Mn^2+离子。与国际法相比,本法具有精密度好、准确度高、快速简便等特点,加标回收率为99.5-100.4%。 相似文献
4.
介绍复合肥中总磷含量的快速测定方法-EDTA络合滴定法,样品溶液中的PO4^3-与Pb^2+、Cl^-形成PbCl2[Pb3(PO4)2]·H2O复盐沉淀,用EDTA滴定过量的Pb^2+。方法快速、准确,可用于生产中间控制和成品复合肥中总磷测定。 相似文献
5.
本文提出一种测定CuSO4含量的螯合滴定方法。该方法是在酸铜镀液中,加入过量的EDTA络合全部的金属离子,再用硫脲、抗坏血酸和1,10-二氮杂菲选择性地分解Cu-EDTA.该方法有效地消除了镀液中Fe^3+、Zn^2+、Al^3+等杂质金属离子对测定结果的干扰。方法简便,结果准确,已被成功用于镀铜生产中CuSO4的测定。 相似文献
6.
本文提出用氟化物、柠檬酸(citricacid)简称CITRA和Na4P2O7掩蔽Fe^3+1、Al^3+、Ca^2+、Mg^2+、Zr^4+、Ti^4+、ΣRE^3+(稀土元素)和Mm^2+等,用EDTA螯合Ni^3+,以二甲酚橙与溴化烷基吡啶(简称XO-CPB)为混合指示剂,用Cu^2+标准溶液返滴定法测定工业硫酸镍中的镍。终点颜色变化敏锐、清晰。实际应用表明,本法具有简便、快速和准确度高。 相似文献
7.
选择性螯合滴定法测定镍是采用过量EDTA螯合镍离子及其它金属离子,然后用SCN^-,C5H5N选择分解Ni-EDTA,释放出EDTA,用Pb(NO3)2标准溶液滴定,从而计算镍的含量。以XO-MTB-CPB为混合指示剂,终点变化敏锐。本法操作简便,结果准确,可用于测定电镀液和镍基合金镀层中的镍。 相似文献
8.
高效液膜分离富集镍基合金镀层中稀土总量 总被引:2,自引:0,他引:2
用TBP-TTA(协同流动载体)、SPAN80和煤油高效液膜体系,研究∑RE^3+迁移行为。在适宜条件下,10min内,∑RE^3+的迁移率达99.5%以上。在同样条件下,常见共存金属离子如Fe^3+、Al^3+、Ni^2+、Cr^3+、Mo^6+、Cu^2+、Co^2+、Zn^2+、Cd^2+等均不被迁移;大量碱金属、碱土金属、Cl、NO3、ClO4、F、SiO3^2-、SO4^2-等离子也不影 相似文献
9.
采用XRD、XPS和XAES、ESR等技术研究,1,4-丁二醇液相脱氢环化合成γ-丁内酯Cu-Zn-AlO催化剂在不同条件下的表现化学态。结果表明:Cu-Zn-AlO催化剂前驱体以Cu^+2形式存在;活化态、反应态表面只是Cu^0,未测出Cu^+、Cu^2+;体相中尚存在部分未还原的Cu^2+;Cu^0微昌有聚集的现象;交联活性测试结果认为:在活化态、反应态中ZnO、Al元素与Cu^0的相互作用, 相似文献
10.
合成了BTADCAB、5,6-Cl-BTADCAB、BTADCABS和5,6-Cl-BTADCABS4种新显色剂,试验了试剂与金属离子的显色反应,发现含有--SO3H分析功能团的BTADCABS和5,6-Cl-BTADCABS仅与Pd^2+起显色反应。同时测定了上述试剂的离解常数。 相似文献
11.
Novel chitosan‐based adsorbent materials were synthesized with a higher fatty diacid diglycidyl as a crosslinking agent, and the adsorption ability of the resulting polymers for several metal ions was evaluated. Selective adsorption for Cu2+ in comparison with other divalent metal ions, such as Ni2+, Pb2+, Cd2+, and Ca2+, was observed with the crosslinked chitosan sorbent at pH 6; however, the adsorption power decreased abruptly as the pH value of the solution decreased. The addition of ethylenediamine tetraacetic acid (EDTA) residues to crosslinked chitosan significantly enhanced the adsorption power for metal ions, especially for Ca2+. The adsorptivity of Ca2+ was dramatically improved with the introduction of EDTA residues, and the value was greater than that obtained with a commercial chelate resin (CR11). Although the adsorption power of the EDTA‐derivatized sorbent for other metal ions was just comparable to that of the CR11 material, the newly synthesized adsorbent could be used for the recovery of metal ions from industrial waste solutions with a relatively wide range of pHs, from 4.0 to 6.0. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 2758–2764, 2004 相似文献
12.
Bombyx mori silk, Antheraea pernyi silk, and wool fibers were chemically modified by treatment with tannic acid (TA) or by acylation with ethylenediaminetetraacetic (EDTA) dianhydride. Kinetics of TA loading or acylation with EDTA‐dianhydride varied from fiber to fiber. B. mori silk and wool displayed the highest weight gains with TA and EDTA‐dianhydride, respectively. The uptake of different metal ions (Ag+, Cu2+, Co2+) by protein fibers, either untreated or chemically modified, was studied as a function of weight gain and pH of the aqueous metal solution. Below pH 7, absorption of metal ions by untreated and TA‐treated fibers was negligible. Acylation with EDTA‐dianhydride enabled protein fibers to absorb and bind significant amounts of metal ions in the acidic and neutral pH range. The levels of metal desorption at acidic pH depended on the fiber‐metal combination. Untreated protein fibers usually displayed the lowest stability of the metal complex. Metal complexes with protein fibers exhibited prominent antimicrobial activity against the plant pathogen Cornebacterium. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 638–644, 2003 相似文献
13.
利用EDTA对重金属离子的螯合作用,将其作为有机阴离子插入到镁铝水滑石的层间,采用共沉淀法制备了复合层状材料EDTA.Mg-Al LDH。通过正交实验确定了NaOH投加量为理论计算值的1.2倍时,合成物的层间阴离子以EDTA4-形式稳定存在。EDTA.Mg-Al LDH处理56 mg/LCd2+溶液的最佳处理条件为:水滑石质量浓度5.0 g/L,反应时间60 min,去除率可达98.20%。并与以无机阴离子Cl-作为插入离子制备的Cl.Mg-Al LDH对56 mg/L的Cd2+溶液的去除率进行了比较,由于层间阴离子EDTA4-对重金属强烈的螯合能力,EDTA.Mg-Al LDH对水中Cd2+的去除效率大大高于Cl.Mg-Al LDH。 相似文献
14.
The adsorption of metal ions (Mo6+, Cu2+, Fe2+, and Fe3+) was examined on chemically modified chitosans with a higher fatty acid glycidyl (CGCs), and the adsorption of Cu2+ was examined on ethylenediamine tetraacetic acid dianhydride modified CGCs (EDTA‐CGCs) synthesized by the reaction of the CGCs with ethylenediamine tetraacetic acid dianhydride. The adsorption of phosphate ions onto the resulting substrate/metal‐ion complex was measured. Mo6+ depicted remarkable adsorption toward the CGCs, although all the Mo6+ was desorbed under the adsorption conditions of the phosphate ions. The other metal ions were adsorbed to some extent on CGCs by chelating to the amino group in the substrate, except for CGC‐1, which had the highest degree of substitution (83.9%). Considerable amounts of Fe2+ were adsorbed onto CGCs; however, only a limited number of phosphate ions was adsorbed onto the substrate/metal‐ion complex. As a result, the following adsorbent/metal‐ion complexes gave higher adsorption ability toward phosphate ions: CGC‐4/Cu2+, CGC‐4/Fe3+, and EDTA‐CGC‐3/Fe3+. Where, CGC‐3 is a chemically modified chitosan with the degree of substitution of 26.5 percentage, and CGC‐4 is one with the degree of substitution of 16.0 percentage. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
15.
Further studies on adsorption of different metal ions by the four dyed and undyed cellulosic substrates namely cotton fibers, bleached bamboo pulp, jute fibers, and sawdust were carried out. Different metal ions adsorbed were Fe2+, Fe3+, Pb2+, and Hg2+. The equilibrium metal adsorption was studied by EDTA method. The control and dyed substrates adsorbed these metal ions to a significant extent, thus providing an effective and cheap method for adsorption of costly but polluting and toxic metals like Pb2+ and Hg2+. The adsorption levels varied up to 95% for various substrate–dye–metal ion combinations. 相似文献
16.
不法企业在钛白粉中常掺入碳酸钙、立德粉、高岭土等违法添加物。针对此现状,建立了钛含量的选择性络合滴定法。方法采用浓硫酸、硫酸铵分解试料,丙三醇作为TiO2+的水解抑制剂,试样溶液pH为2.0~4.0,用过量的乙二胺四乙酸二钠(EDTA)络合TiO2+及其他金属离子,建立以二甲酚橙(XO)-甲基百里酚蓝(MTB)-十二烷基硫酸钠(SDS)为混合指示剂三元体系,用氯化锌标准溶液回滴过量的EDTA,酒石酸钾钠选择性分解TiO-EDTA,再用氯化锌标准溶液滴定释放的EDTA。该方法的加标回收率为98.78%~100.18%、相对标准偏差(RSD)为0.10%~
0.78%。该方法操作简便,终点变化清晰且敏锐,适用于伪劣钛白粉中二氧化钛含量的测定。 相似文献
17.
高分子重金属絮凝剂对镍离子螯合能力的研究 总被引:2,自引:0,他引:2
研究了高分子重金属絮凝剂(PEX)对镍离子螯合能力的大小,以含镍水样作为处理对象,通过一系列试验证明:PEX对镍离子的螯合能力强,生成的螯合体溶解度小,对低浓度的镍离子废水处理效果好。废水中一定量的EDTA或Ca2+的存在,不仅不会影响PEX对镍离子的去除,而且会大大促进这一过程。 相似文献
18.
利用铜试剂与Cu2+生成黄棕色络合物的特效显色反应,用分光光度法测定镀镍溶液中的铜杂质.用EDTA掩蔽镍离子和铁离子,在氨碱性条件下显色,显色液pH≈9.2.以镀液底色作参比,在λ=450 nm处测定.实验表明,测定结果的相对平均偏差为2%,能够满足监控镀镍溶液中铜杂质的要求. 相似文献