Separation of heavy metal from water samples--The study of the synthesis of complex compounds of heavy metal with dithiocarbamates.

The toxicity and persistence of heavy metal (HM) ions may cause several problems to marine organisms and human beings. For this reason, it is growing the interest in the chemistry of sulphur donor ligands such as dithiocarbamates (DDTC), due to their applications particularly in analytical chemistry sciences. The aim of this work has been the study of heavy metal complexes with DDTC and their application in separation techniques for the preconcentration and/or removing of heavy metals from the water solutions or the water ecosystems prior to their analysis. The HM-DDTC complexes were prepared and characterized by elemental analysis, FTIR and UV-Vis spectroscopic methods. The elemental analysis and the yield of the synthesis (97.5-99.9%) revealed a good purity of the complexes. High values of complex formation yields of HM-DDTC complexes is an important parameter for quantitatively removing/and or preconcentration of heavy metal ions from water solution even at low concentration of heavy metals. Significant differences founded between the characteristic parameters of UV/Vis (λmax and ϵmax) and FTIR absorption spectra of the parent DDTC and HM-DDTC complexes revealed the complex formation. The presence of the peaks at the visible spectral zone is important to M(nd(10-m))-L electron charge transfer of the new complexes. The (C=N) (1450-1500 cm(-1)) and the un-splitting (C-S) band (950-1002 cm(-1)) in HM-DDTC FTIR spectra are important to the identification of their bidentate mode (HM[S2CNC4H10]2). The total CHCl3 extraction of trace level heavy metals from water samples after their complex formation with DDTC is reported in this article.

First survey of atmospheric heavy metal deposition in Kosovo using moss biomonitoring.

Bryophytes act as bioindicators and bioaccumulators of metal deposition in the environment. The atmospheric deposition of Cd, Cr, Cu, Fe, Hg, Ni, Mn, Pb, and Zn in Kosovo was investigated by using carpet-forming moss species (Pseudocleropodium purum and Hypnum cupressiforme) as bioindicators. This research is part of the European moss survey coordinated by the ICP Vegetation, an International Cooperative Programme reporting on the effects of air pollution on vegetation to the UNECE Convention on Long-range Transboundary Air Pollution. Sampling was performed during the summer of 2011 at 25 sampling sites homogenously distributed over Kosovo. Unwashed, dried samples were digested by using wet digestion in Teflon tubes. The concentrations of metal elements were determined by atomic absorption spectrometry (AAS) equipped with flame and/or furnace systems. The heavy metal concentration in mosses reflected local emission sources. The data obtained in this study were compared with those of similar studies in neighboring countries and Europe (2010-2014 survey). The geographical distribution maps of the elements over the sampled territory were constructed using geographic information system (GIS) technology. The concentrations of Cr, Ni, Pb, and Zn were higher than the respective median values of Europe, suggesting that the zones with heavy vehicular traffic and industry emission input are important emitters of these elements. Selected zones are highly polluted particularly by Cd, Pb, Hg, and Ni. The statistical analyses revealed that a strong correlation exists between the Pb and Cd content in mosses, and the degree of pollution in the studied sites was assessed.

4-Nitro-phenyl 2-bromo-2-methyl-propano-ate.

In the title compound, C(10)H(10)BrNO(4), the planes of the carboxyl-ate and nitro groups are rotated by 60.53 (13) and 6.4 (3)°, respectively, to the benzene ring. In the crystal, inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into zigzag chains parallel to the c axis.

3-Benzyl-3-hy-droxy-2-phenyl-3H-indole 1-oxide.

The asymmetric unit of the title compound, C(21)H(17)NO(2), contains two crystallographically independent mol-ecules of similar geometry. The indole ring systems form dihedral angles of 8.30 (5) and 9.58 (5)° with the attached phenyl rings, and 56.96 (5) and 57.68 (5)° with the aromatic rings of the respective benzyl groups. The mol-ecular conformations are stabilized by intra-molecular C-H⋯O hydrogen bonds. In the crystal structure, centrosymmetrically related pairs of mol-ecules are linked into dimers through pairs of inter-molecular O-H⋯O hydrogen bonds, generating 12-membered rings with R(2) (2)(12) motifs. The dimers are further linked into a three-dimensional network by C-H⋯O inter-actions.

1-[2-(2,4-Dichloro-phenyl)-pent-yl]-1H-1,2,4-triazole.

The title compound, C(13)H(15)Cl(2)N(3), also known as penconazole, crystallizes as a racemate. The dihedral angle between the benzene and triazole rings is 24.96 (13)°. In the crystal structure, mol-ecules are linked into chains running parallel to the c axis by inter-molecular C-H⋯N hydrogen-bonding inter-actions.

2,2-Diphenyl-benzo[c]quinoline-1-ox-yl.

In the title compound, C(25)H(18)NO, a stable phenanthridinic nitroxide, the ring containing the nitroxide function assumes a twist-boat conformation and the dihedral angle formed by adjacent benzene rings is 21.78 (5)°. The phenyl substituents at position 2 are approximately orthogonal to each other, forming a dihedral angle of 81.04 (4)°. The crystal structure is stabilized by an intra-molecular C-H⋯O hydrogen bond and by C-H⋯π inter-actions.