• Bulletin of the Korean Chemical Society
• /
• 제31권5호
• /
• pp.1377-1380
• /
• 2010

• 한국환경보건학회지
• /
• 제24권3호
• /
• pp.1-5
• /
• 1998

A spectrophotometric method was developed for the acidic solution stripped after an extraction of 0.5 to 2.5 ppm of Lead(II) from 50 mL of $Na_2S_2O_3$ solution into chloroform as the ion-pairs formed between their thiosulfate complexes and alkylamine, Aliquat336. Pb(II) in the stripped solution forms an complex with DDTC in pH 7.3 buffer solution, and was developed in yellow by copper replacement. The ydlow-colored solution have the maximum absorbance at 435 nm in the measurement of absorbance by UV-Visible spectrophotometer. The interference ions such as Fe(III), Hg (II), Al(III), Co, Cu, Ni, Zn, Ca, Sn, have great effects on the extraction, but they were overcomed by the usage of adequate masking agents before an extraction. At last, a good result was obtained in applying this method to synthetic water.

• 응용화학
• /
• 제15권2호
• /
• pp.113-116
• /
• 2011

A sensitive and selective determination method of Fe(II) ion by luminol-H₂O₂ system using a chelating reagent has been presented. A metal ion-chelating ligand complex such as Fe(II)-diethylenetriamine pentaacetic acid (DTPA) produced higher chemiluminescence (CL) intensity as well as longer lifetime in luminol-H₂O₂ system than metal exist as free ions. Furthermore, the catalytic activity of Cu(II) and Pb (II) complexes with chelating reagents in luminol-H₂O₂ system was lost since chelating reagents act as a masking agent although free Cu(II) and Pb(II) ions have high catalytic activity. On the optimized conditions, the calibration curve of Fe(II) ion was linear over the range from 1.0×10^-7 to 2.0×10^-5 M with correlation coefficient of 0.996. The detection limit was calculated to be 4.0×10^-8 M.

• 폴리머
• /
• 제27권4호
• /
• pp.330-339
• /
• 2003

폴리(스티렌-co-디비닐벤젠) 수지 페닐고리의 클로로메틸화를 통해 메틸렌티올기를 도입한 수지 (I), 폴리(스티렌-co-메틸 메타아크릴레이트-co-디비닐벤젠) 공중합체의 페닐고리와 에스터기에 클로로메틸화 반응을 거쳐 각각 메틸렌티올기를 도입하여 중금속 이온들과의 배위결합에 필요한공간개념을 배려한 수지(II) 및 폴리(스티렌-co-디비닐벤젠) 수지의 페닐고리를 클로로설폰화한 후, 소디움하이드로술파이드로 티오설폰산화한 수지 (III) 등 3가지 종류의 티올계 구상형 수지들을 합성하였다. 이어, 이들 킬레이트 수지들에 대한 중금속 이온의 흡착경향을 평가한 결과, 티올기 함유 I형 킬레이트 수지는 Hg$^{2＋}$에 대해서만 선택적 흡착성을 보였고, 티올기 함유 II형 킬레이트 수지는 Hg$^{2＋}$에 대한 흡착성능이 보다 향상되었으며, Cu$^{2＋}$, Pb$^{2＋}$, C$d^{2＋}$ 및 Cr$^{3+}$ 등의 몇몇 중금속 이온들에 대해서도 약간의 흡착능을 보였다. 다른 한편으로, 친수성의 티오설폰산기 함유 III형 킬레이트 수지는 효율적 흡착체로서 Hg$^{2＋}$, Cu$^{2＋}$, Ni$^{2＋}$, Co$^{2＋}$ 및 Cr$^{3+}$ 등의 중금속 이온들은 물론, 특히 C$d^{2＋}$ 및 Pb$^{2＋}$에 높은 흡착능을 보였다.

• Bulletin of the Korean Chemical Society
• /
• 제34권12호
• /
• pp.3615-3620
• /
• 2013

Two novel copper(II) bromide complexes with pyridine containing Schiff base ligands, $Cu(pmed)Br_2$ and $Cu(pmed)Br_2$ where pmed = N'-((pyridin-2-yl)methylene)ethane-1,2-diamine (pmed) and dpmed = N,N-diethyl-N'-((pyridin-2-yl)methylene)ethane-1,2-diamine (dpmed) were synthesized and characterized using X-ray single crystal structure analysis, optical and magnetic susceptibility measurements. Crystal structural analysis of $Cu(pmed)Br_2$ showed that the copper(II) ion has a distorted square-pyramidal geometry with the trigonality index of ${\tau}=0.35$ and two intermolecular hydrogen bonds, which result in the formation of two dimensional networks in the ab plane. On the other hand, $Cu(pmed)Br_2$ displayed a near square-pyramidal geometry with the value of ${\tau}=0.06$. In both compounds, the NNN Schiff base and one Br atom occupy the basal plane, whereas the fifth apical position is occupied by the other Br atom at a greater Cu-Br apical distance. The reported complexes show $g_{\mid}$ > $g_{\perp}$ > 2.0023 with a $d_{x2-y2}$ ground state and a penta-coordinated square pyramidal geometry. Variable temperature magnetic susceptibility measurements showed that the developed copper(II) complexes follow the Curie-Weiss law, that is there are no magnetic interactions between the copper(II) ions since the Cu--Cu distance is too far for magnetic contact.

• Bulletin of the Korean Chemical Society
• /
• 제27권11호
• /
• pp.1757-1762
• /
• 2006

A solvent sublation using salphen as a ligand was studied and applied for the determination of trace Ni(II), Co(II) and Cu(II) in water samples. The fundamental study was investigated by a solvent extraction process because the solvent sublation was done by extracting the floated analytes into an organic solvent from the aqueous solution. The salphen complexes of Ni(II), Co(II) and Cu(II) ions were formed in an alkaline solution of more than pH 8 and then they were extracted into m-xylene. It was known that the each metallic ion formed 1 : 1 complex with the salphen and the logarithmic values of extraction constants for the complexes were 3.3 5.1 as an average value. Based on the preliminary study, the procedure was fixed for the separation and concentration of the analytes in samples. Various conditions such as the pH of solutions, the influence of $NaClO_4$, the bubbling rate and time of $N_2$ gas, and the type of organic solvent were optimized. The metal-salphen complexes could be extracted into m-xylene from the solution of more than pH 8, but the pH could be shifted to acidic solution of pH 6 by the addition of $NaClO_4$. In addition, the solvent sublation efficiency of the analytes was increased by adding $NaClO_4$. The recovery of 97-115% was obtained in the spiked samples in which given amounts of 0.3 mg/L Ni(II), 0.8 mg/L Co(II) and 0.04 mg/L Cu(II) were added.

• 대한화학회지
• /
• 제52권2호
• /
• pp.148-154
• /
• 2008

2-Propylpiperidine-1-carbodithioate(PPCD)I 로 수식화한 octadecyl로 결합된 실리카 막 디스크로 구리(II) 이온의 잔유양의 추출과 간단하고 빠르게 원자흡수분광법(AAS)으로의 정량법을 소개한다. 추출효율과 흐름속도, pH, 형 태, 벗김 산의 가장 적은 양에 대해 연구되었다. Anthraquinone 유도체의 2 mg로 수식한 막디스크의 최대 용량은 425 μg Cu2+ 이었다. 제안한 방법의 검출한계는 7 ng/ml이다. 이 방법은 다른 시료와 온천수 시료로부터 Cu2+의 회수에 적용하 였다.

• 공업화학
• /
• 제32권5호
• /
• pp.589-598
• /
• 2021

The purpose of this study was to analyze the efficiency with which phosphorylated spent coffee grounds (PSCG) remove cationic Cu(II) ions from an aqueous solution. The pHpzc of the SCG was 6.43, but it was lowered to 3.96 in the PSCG, confirming that an acidic functional group was attached to the surface of the PSCG. According to FT-IR analysis, phosphorylation of the SCG added P=O, P-O-C (aromatic), P=OOH, and P-O-P groups to the surface of the adsorbent, and the peaks of the carboxyl and OH groups were high and broad. Also, the specific surface area, mesopore range, and ion exchange capacity increased significantly by phosphorylation. The adsorption kinetics and isothermal experiments showed that Cu(II) adsorption using SCG and PSCG was explained by PSO and Langmuir models. The maximum Langmuir adsorption capacity of SCG and PSCG was 42.23 and 162.36 mg/g, respectively. The adsorption process of both SCG and PSCG was close to physical adsorption and endothermic reaction in which the adsorption efficiency increased with temperature. PSCG was very effective in adsorbing Cu(II) in aqueous solution, which has great advantages in terms of recycling resources and adsorbing heavy metals using waste materials.

• Environmental Engineering Research
• /
• 제18권1호
• /
• pp.45-53
• /
• 2013

Biocarrier beads with dead biomass, Bacillus drentensis, immobilized in polymer polysulfone were synthesized to remove heavy metals from wastewater. To identify the sorption mechanisms and theoretical nature of underlying processes, a series of batch experiments were carried out to quantify the biosorption of Pb(II) and Cu(II) by the biocarrier beads. The parameters obtained from the thermodynamic analysis revealed that the biosorption of Pb(II) and Cu(II) by biomass immobilized in biocarrier beads was a spontaneous, irreversible, and physically-occurring adsorption phenomenon. Comparing batch experimental data to various adsorption isotherms confirmed that Koble-Corrigan and Langmuir isotherms well represented the biosorption equilibrium and the system likely occurred through monolayer sorption onto a homogeneous surface. The maximum adsorption capacities of the biocarrier beads for Pb(II) and Cu(II) were calculated as 0.3332 and 0.5598 mg/g, respectively. For the entire biosorption process, pseudo-second-order and Ritchie second-order kinetic models were observed to provide better descriptions for the biosorption kinetic data. Application of the intra-particle diffusion model showed that the intraparticle diffusion was not the rate-limiting step for the biosorption phenomena. Overall, the dead biomass immobilized in polysulfone biocarrier beads effectively removed metal ions and could be applied as a biosorbent in wastewater treatment.

• 대한화학회지
• /
• 제53권1호
• /
• pp.27-33
• /
• 2009

실제 시료에 들어있는 흔적량 Cd(II)를 2-mercaptobenzothiazole이 내포되어 있는 미세결정 p-dichlorobenzene에 예비농축시킨 후 정량하는 감도좋은 방법을 개발하였다. 시료 용액의 pH, 킬레이트제 2-mercaptobenzothiazole의 양, 흡착제 p-dichlorobenzene-2-MBT의 양 그리고 시료 용액의 흐름속도 등 여러 실험조 건을 최적화하였다. 여러 공존이온에 대한 방해효과를 조사하였는데 다른 이온들보다 Cu(II)가 비교적 심하게 방해를 하였다. 그러나 Cu(II)에 의한 방해는 시료용액의 tartrate 이온의 농도를 0.01 M이 되게 하든지 또는 0.20 g의 p-dichlorobenzene에 내포된 2-mercaptobenzothiazole의 양을 0.08 g에서 0.12 g이 되게 하면 충분히 없앨 수 있었다. 이 방법에 의해 얻어진 직선 감응범위, 상관계수($R^2$) 및 검출한계는 각각 0.5-30 ng $mL^{-1}$, 0.9962, 및 0.39 ng $mL^{-1}$로서, p-dichlorobenzene을 흡착제 매질로 이용하여 매우 좋은 결과를 얻었다. 이 방법을 실제 시료에 적용할 수 있을지를 확인하기 위해 수용액 시료(폐수, 시냇물, 그리고 저수지물)와 플라스틱 시료에 응용하였다. 회수율은 93-104% 정도였으며, ICP-MS를 이용하여 얻은 값과 이 방법으로 얻은 값은 F 시험법에 의하면 95% 신뢰수준에서 차이가 없는 것으로 나타났다. 실험 결과들로부터 이 방법은 여러 실제 시료에 들어있는 Cd(II)을 농축 정량하는데 응용할 수 있음을 알 수 있었다.