三乙烯四胺修饰交联壳聚糖树脂的制备及其对痕量镉的吸附性能研究

以戊二醛、环氧氯丙烷为交联剂,用三乙烯四胺改性,由壳聚糖合成了一种新型的三乙烯四胺修饰交联壳聚糖微球(CRN)分离树脂,研究了不同条件下CRN对Cd2+的吸附性能。在pH6.0时,CRN能定量吸附溶液中的痕量Cd2+,其静态饱和吸附容量为31.0 mg/g。吸附在CRN上的Cd2+可用0.5 mol/L的H2SO4洗脱,用火焰原子吸收法测定洗脱液中Cd2+的含量。本法对Cd2+的检出限(3σ)为24.6 ng/mL,相对标准偏差(RSD)为2.1%(n=11,c=1.0μg/mL),加标回收率在97.3%～104.0%。该方法可用于矿渣中痕量镉的测定。     

新型固化单宁树脂的合成及其对痕量钯(Ⅱ)的吸附性能研究

报道了新型固化单宁树脂的合成方法及其对钯(Ⅱ)分离富集的研究.探讨了溶液pH值、温度、洗脱条件及干扰离子等对钯(Ⅱ)分离富集的影响.在pH＝3,温度为25℃的条件下恒温水浴振荡20 min,痕量钯(Ⅱ)可被固化单宁树脂定量富集,其静态饱和吸附容量为44.91 mg·g-1.吸附的钯(Ⅱ)可用0.2 mol·L-1硫脲与0.2 mol·L-1盐酸混合液(体积比为1∶1)完全洗脱, 用火焰原子吸收光谱法(FAAS)测定.该法对钯(Ⅱ)的检出限(3σ,n=11)为0.091 μg·mL-1,相对标准偏差为2.69%(n=7),线性范围为0.16～8.2 μg·mL-1,加标回收率在97%～100%之间.方法用于催化剂中钯(Ⅱ)的测定,结果满意.     

交联壳聚糖分离富集-火焰原子吸收法测定水样中痕量银

以甲醛、环硫氯丙烷为交联剂,由壳聚糖合成了一种新型的交联壳聚糖微球(FCCIS)分离树脂,研究了不同条件下FCCTS对Ag(Ⅰ)的吸附性能.在pH 3.6时FCCTS对Ag(Ⅰ)定量吸附,吸附在树脂上的Ag(Ⅰ)可用0.5 moL/L的氨水将其洗脱,用火焰原子吸收光谱测定.该法对Ag(Ⅰ)的检出限为61 ng/mL(3σ,n=8),相对标准偏差为2.2%(n=7,ρ=2μg/mL),线性范围为0.05～4μg/mL,加标回收率在98.8%～101.7%之间.该法已用于水样中痕量银测定.     

萃取富集-火焰原子吸收光谱法测定食品中痕量银

建立了萃取富集-火焰原子吸收法测定食品中痕量银的新方法.在硫氰酸钾、十六烷基三甲基溴化铵和氯化钠溶液体系中,银离子能被定量萃取到乙酸乙酯中,从而起到富集作用,取乙酸乙酯于火焰原子吸收光谱仪测定其中的银元素含量,提高了测定灵敏度和选择性.结果显示:银在0-200ng/mL内线性良好,r=0.999 3,测定银的灵敏度(特...     

固载硫杂杯芳烃树脂分离富集-火焰原子吸收法测定痕量银

报道了色谱301固载硫杂杯芳烃树脂分离预富集-火焰原子吸收光谱法测定痕量银的新方法。探讨了固载硫杂杯芳烃树脂对银的吸附原理与最佳条件。将含Ag 试液在pH=10、温度为23±2℃的条件下恒温震荡10min,静置10min,Ag 可被树脂定量富集被吸附的Ag 可用5mL酸性硫脲(0.15mol/LHCl 0.15mol/L硫脲)完全洗脱,洗脱液中的银用火焰原子吸收光谱法测定。该法对银的检出限为0.17μg/L(3σ,n=11);线性范围为0.006~3mg/L。对0.18mg/L的Ag 标液进行7次测定,RSD=1.53%,回收率在99.9%~105.0%之间。用于“二次资源”锌矿渣和环境水样中痕量银的测定,结果满意。     

纳米二氧化钛对痕量铅的吸附性能研究

提出了纳米TiO2分离富集, 火焰原子吸收光谱法测定水样中痕量铅的新方法.考察了铅在纳米TiO2上的吸附动力学、最佳酸度和吸附容量.实验结果表明：在最佳实验条件下,纳米TiO2能定量、快速地吸附水中的痕量Pb^2＋,其静态吸附容量为17.90 mg/g.吸附在纳米TiO2上的Pb^2＋可用0.1 mol/L HNO3＋0.1 mol/L CH3COOH完全洗脱.对Pb2＋的检出限为2.57 ng/mL, 相对标准偏差为2.5% （n=11, ρ=0.10 μg/mL）,加标回收率在94.5%～102.5%之间.可用于实际水样中铅的测定.     

固载硫杂杯芳烃树脂分离富集-火焰原子吸收法测定痕置银

报道了色谱301固载硫杂杯芳烃树脂分离预富集-火焰原子吸收光谱法测定痕量银的新方法。探讨了固载硫杂杯芳烃树脂对银的吸附原理与最佳条件。将含Ag^＋试液在pH=10、温度为23±2℃的条件下恒温震荡10min，静置10min，Ag^＋可被树脂定量富集被吸附的Ag^＋可用5mL酸性硫脲（0．15mol／L HCl＋0．15mol／L硫脲）完全洗脱，洗脱液中的银用火焰原子吸收光谱法测定。该法对银的检出限为0．17μg／L（3σ，n=11）；线性范围为0．006—3mg／L。对0．18mg／L的Ag^＋标液进行7次测定，RSD=1．53％。回收率在99．9％-105．0％之间。用于“二次资源”锌矿渣和环境水样中痕量银的测定，结果满意。     

纳米SiO_2分离富集-火焰原子吸收法测定水中痕量银

研究了纳米SiO_2分离富集-火焰原子吸收法测定水中痕量银的新方法.考察了溶液pH、吸附时间、洗脱条件和干扰离子等因素对Ag~+分离富集的影响,确定了纳米SiO_2对Ag~+吸附的最佳条件.结果表明:在pH 4.1时,纳米SiO_2能定量吸附银,吸附在纳米SiO_2上的Ag~+可用0.5 mol/L HCl+0.5 mol/L硫脲定量洗脱.该法对银的检出限为0.77 ng/mL(3σ,n=11);线性范围为0.005～1.5μg/mL,对0.5μg/mL的Ag~+标液进行7次测定,RSD为3.6%,回收率在94.0%～101.5%之间;方法可用于环境水样中痕量银的测定.     

火焰原子吸收光谱法测定水痕量银

测定银的方法有高温石墨炉原子吸收光谱法和巯基棉富集高碘酸钾吸光光度法[1] ,但前者受仪器设置的限制 ,不易普及 ,后者由于水中银含量很低 ,往往受灵敏度的限制 ,需要富集 ,必须向水样中加入许多试剂 ,操作比较复杂 ,易造成误差。本文采用加热浓缩[2 ] 火焰原子吸收光谱法 ,操作简便、快速 ,精确度和准确度都比较理想 ,适用天然水样的测定。1　试验部分1.1　仪器与试剂ＷＦＸ 1Ｆ2Ｂ2型原子吸收分光光度计 (北京瑞利分析仪器公司 )银标准溶液 :1.0 μｇ·ｍｌ- 1水为离子交换水1.2　试验方法1.2 .1　操作方法取水样 2 0 0ｍｌ及 0 ,0 .5 ,…     

痕量银的液膜富集与原子吸收法测定

研究了分离与富集痕量银的液条件,摸索出一种新的液膜体系ＴＯＡＮ２０５煤油０－ＮＨ３．Ｈ２Ｏ,提出了最佳富集条件。经５次提取分离,富集倍数可达８２倍。回收率在９８％以上。与火焰原子回收法相结合可测ｎｇ／ｍｌ级的Ａｇ＾＋此法用于富集地质标样中的痕量银,相对标准偏差为２．４％（ｎ＝１０）     

负载硫杂杯芳烃树脂微柱分离富集-火焰原子吸收法测定痕量金

建立了大孔径树脂D101负载硫杂杯芳烃树脂微柱分离富集-火焰原子吸收光谱法测定痕量金的新方法。探讨了负载硫杂杯芳烃树脂对金的吸附原理与最佳条件。该法对金的检出限为0.23 ng/mL(3σ,n=11),线性范围为0.01~1μg/mL。对0.2μg/mL的Au 标液进行5次测定,RSD=2.1%,加标回收率在98.4%~103.3%之间。方法用于矿渣样中痕量金的分析。     

Synthesis of amidinothioureido-silica gel and its application to flame atomic absorption spectrometric determination of silver, gold and palladium with on-line preconcentration and separation

A simple and highly selective flow injection (FI) on-line preconcentration and separation flame atomic absorption spectrometric (FAAS) method was developed for the determinations of trace amounts of silver, gold and palladium. The selective preconcentration of the noble metals was achieved in a wide range of sample acidity (0.1-6 M HNO₃ or HCl) on a microcolumn packed with amidinothioureido-silica gel (ATuSG). The analytes retained on the column were effectively eluted with 5.0% thiourea solution. The analytical procedure was optimized for sample acidity, elution, interferences, flow rate of sampling and eluting, and concentration of sample. Common co-existing cations and anions did not interfere with the preconcentration and determination of the three metals. At a sample loading flow rate of 4.5 ml min⁻¹ with 60 s preconcentration, detection limits (3σ) of 1.1 ng ml⁻¹ Ag, 13 ng ml⁻¹ Au and 17 ng ml⁻¹ Pd were obtained. The precisions (R.S.D., n=11) were 1.2% for Ag, 1.2% for Au and 1.7% for Pd, respectively. The detection limits can be further improved by increasing sample volume. The analytical results obtained by the proposed method for a number of standard reference materials were in good agreement with the certified values.     

A solid phase extraction using a chelate resin immobilizing carboxymethylated pentaethylenehexamine for separation and preconcentration of trace elements in water samples

A chelate resin immobilizing carboxymethylated pentaethylenehexamine (CM-PEHA resin) was prepared, and the potential for the separation and preconcentration of trace elements in water samples was evaluated through the adsorption/elution test for 62 elements. The CM-PEHA resin could quantitatively recover various elements, including Ag, Cd, Co, Cu, Fe, Ni, Pb, Ti, U, and Zn, and rare earth elements over a wide pH range, and also Mn at pH above 5 and V and Mo at pH below 7. This resin could also effectively remove major elements, such as alkali and alkaline earth elements, under acidic and neutral conditions. Solid phase extraction using the CM-PEHA resin was applicable to the determination of 10 trace elements, Cd, Co, Cu, Fe, Mn, Mo, Ni, Pb, V, and Zn, in certified reference materials (EnviroMAT EU-L-1 wastewater and ES-L-1 ground water) and treated wastewater and all elements except for Mn in surface seawater using inductively coupled plasma atomic emission spectrometry. The detection limits, defined as 3 times the standard deviation for the procedural blank using 500 mL of purified water (50-fold preconcentration, n = 8), ranged from 0.003 μg L⁻¹ (Mn) to 0.28 μg L⁻¹ (Zn) as the concentration in 500 mL of solution.     

CL-7402萃淋树脂分离富集铅的研究及其应用

通过静态和动态实验,研究了CL-7402萃淋树脂吸附铅的性能和减压微色谱柱分离富集铅的最佳条件。实验表明,此萃淋树脂吸附快,吸附容量大。在减压条件下,以1mol/LHBr为上柱介质,2mol/LHNO3为洗脱液,可使铅与铜、铁等金属离子快速分离。采用三溴偶氮胂光度法测定样品中的铅。     

Development of a flow system for the determination of low concentrations of silver using Moringa oleifera seeds as biosorbent and flame atomic absorption spectrometry

In this study a method for the determination of low concentrations of silver in waters using solid-phase extraction with a flow injection analysis system and detection by flame atomic absorption spectrometry (FAAS) was developed. Moringa oleifera seeds were used as a biosorbent material. Chemical and flow variables of the on-line preconcentration system such as sample pH and flow rate, preconcentration time, eluent concentration and sorbent mass were studied. The optimum preconcentration conditions were obtained using sample pH in the range of 6.0-8.0, preconcentration time of 4 min at a flow rate of 3.5 mL min^− 1, 0.5 mol L^− 1 HNO₃ eluent at a flow rate of 4.5 mL min^− 1 and 35 mg of sorbent mass. With the optimized conditions, the preconcentration factor, precision, detection limit and sample throughput were estimated as 35 (for preconcentration of 14 mL sample), 3.8% (5.0 μg L^− 1, n = 7), 0.22 μg L^− 1 and 12 samples per hour, respectively. The developed method was successfully applied to mineral water and tap water, and accuracy was assessed through analysis of a certified reference material for water (APS-1071 NIST) and recovery tests, with recovery ranging from 94 to 101%.     

中孔分子筛P1 23-SH分离富集-火焰原子吸收光谱法测定礼花弹中银

制备了中孔分子筛P123-SH,并对其用于吸附银离子的条件进行了探索。试验发现在温度为(20±1)℃,介质pH值为3.6时,振荡吸附10 min,吸附容量为15.97 mg·g~(-1),吸附率可达98.5%。吸附在中孔分子筛P123-SH上的银离子可用0.2 mol·L~(-1)盐酸-0.1 mol·L~(-1)硫脲溶液5 mL完全洗脱回收,用火焰原子吸收光谱法测定洗脱液中痕量银的含量。银的质量浓度在0.008～0.24 mg·L~(-1)范围内与其吸光度呈线性关系,方法的检出限(3σ)为0.64μg·L~(-1)。方法用于礼花弹样品中银含量的测定,加标回收率在97.5%～115.0%之间,相对标准偏差(n=7)为2.4%。     

Determination of trace amounts of vanadium by UV-vis spectrophotometric after separation and preconcentration with modified natural clinoptilolite as a new sorbent

Natural clinoptilolite was used as a sorbent material for solid phase extraction and preconcentration of vanadium. The clinoptilolite was first saturated with a cation such as nickel(II) and then modified with benzyldimethyltetradecyleammonium chloride (BDTA) for increasing sorption of 4-(2-pyridylazo)resorcinol (PAR). Vanadium–PAR complex was quantitatively retained on the sorbent by the column method at the pH range 6.2–7.0 at a flow rate of 1 mL min⁻¹. It was removed from the column with 5.0 mL of dimethylformamide solution at a flow rate of 0.8 mL min⁻¹ and determined by UV–vis spectrophotometry at λ_max = 550 nm. 0.031 μg of vanadium can be concentrated from 450 mL of aqueous sample (where detection limit as 0.07 ng mL⁻¹ with preconcentration factor of 90). Relative standard deviation for eight replicate determination of 5.0 μg of vanadium in final solution is 2.1%. The interference of number of anions and cations has been studied in detail to optimize the conditions and method was successfully applied for determination of all vanadium as V(IV) form in standard samples.     

二苯硫脲纤维分离富集原子吸收法测定地质样品中痕量金

采用自行研究合成的二苯硫脲纤维素分离富集，并用火焰原子吸收法测定了地质样品中痕量金，系统研究了题示方法的各种条件，该法简便快速，测定准确，经济实用，具有推广价值。