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This work reports the synthesis of an innovative multifunctional carbon nitride based adsorbent and its successful application for the removal of crystal violet (CV) and methylene blue (MB) from wastewater. The functionalized graphitic carbon nitride (f/g-CN) adsorbent was produced by the pyrolysis of melamine followed by thermal alkali treatment to introduce OH, NH

Polyacrylonitrile nanoparticles grafted on ethylene diamine functionalized partially reduced graphene oxide (PAN-PRGO) was prepared via in situ emulsion polymerization and was further modified to contain amidoxime, amdinoethylene diamine, and carboxylic groups on the surface of the graphene nanosheets via partial hydrolysis of the nitrile groups on the polymer chains of the composite using (4% NaOH, 20 min) (HPAN-PRGO). The properties and morphologies of the prepared composites were compared through FTIR, UV–Vis, Raman spectra, XRD, SEM, TEM, and XPS analysis. The results revealed that polyacrylonitrile nanoparticles were grafted on the surface of the aminated graphene oxide nanosheets via the reaction between the free amino groups of the ethylene diamine modified graphene oxide nanosheets and nitrile groups of acylonitrile (AN). The obtained HPAN-PRGO composite was evaluated for its chelating property with Hg(II) ions. The effect of initial pH, initial concentration of the Hg(II), adsorbent dose, and contact time on the extraction of Hg(II) ions using HPAN-PRGO were investigated. The adsorption experiments indicated that HPAN-PRGO exhibits higher affinity toward Hg(II). The maximum uptake capacity for the extraction of Hg(II) ions on HPAN-PRGO was 324.0 mg/g at pH 5. The HPAN-PRGO shows a 100% removal of Hg(II) at concentrations up to 50 ppm, and the adsorption is exceptionally rapid showing more than 80.0% removal within 15 min and 100.0% of qe within 1.5 h at 800 ppm concentration. The Langmuir isotherm model and pseudo-second-order kinetic model have showed good fitness with the practical data. The XPS analysis of HPAN-PRGO before and after adsorption revealed the chelation adsorption mechanism between mercury and amine, amide, amidoxime, and carboxylic groups. After six adsorption–desorption cycles, the HPAN-PRGO could retain more than 90.0% of its original adsorption capacity. These results confirmed that HPAN-PRGO has exceptional performance for the removal of Hg(II) from wastewater.

A novel chelating adsorbent, based on the functionalization of activated carbon (AC) derived from water hyacinth (WH) with melamine thiourea (MT) to form melamine thiourea-modified activated carbon (MT-MAC), is used for the effective removal of Hg

The preparation of new complexes containing 2-amino-4,6-mercaptotriazine (HAT) [Zn(AT)2(H2O)2], [Zn(bpy)(AT)Cl(H2O)], [Zn(PPh3)2(AT)Cl(H2O)] and cis-[Mo2O5(AT)2] is reported. The structures of these complexes are discussed using IR, NMR, UV–Vis, and EI-mass spectra, elemental analysis, molar conductivity and thermal measurements. HAT coordinates to the central metal ions through the deprotonated cyclic-N(1) and amino-N(2) or mercapto-S(6) atoms (AT−) in mononegative bidentate manner. The stoichiometries and the formation constants of Zn(II) complexes in solution were calculated using Job's method. The anticancer activities of some of the complexes were examined against The human breast cancer MDA-MB231 cell line. The IC50 values for cell growth proliferation were ranged from 24.57 ± 0.2 to 49.89 ± 0.4 μM, while that for the standard reference drug, cisplatin, was 8.72 ± 0.5 μM.

The purpose of this work was to incorporate amine and thiol groups onto the surface of activated carbon (MT-MAC) derived from water hyacinth through amidation reaction between the amino groups of melamine thiourea (MT) and the carboxyl groups of activated carbon (OAC) in presence of dicyclohexylcarbodiimide as a coupling agent. The prepared MT-MAC exhibited extensive potential for the extraction of toxic metal ions Hg(II), Pb(II) and Cd(II) from wastewater. The prepared MT-MAC was characterized by different techniques like BET, SEM, XPS, and FTIR analysis. The results displayed that the total pore volume and surface area of OAC were found to be 864.52 m2 g-1 and 0.5216 m3 g-1, respectively and decreased up on modification with melamine thiourea to 493.78 m2 g-1 and0.2916 m3 g-1.FTIR spectra confirmed the incorporation of amine and thiol groups on the surface of OAC by the appearance of new peaks at 1625 cm-1 and 3332 cm-1 corresponding to the C=O stretching vibration of the NHCO (amide), and N-H stretching vibration, respectively. XPS displayed two new peaks due to S2p and N1s in the MT-MAC survey scan. The MT-MAC adsorbent showed high capacities for the removal of Hg(II) ( 292.6 mg.g-1), Pb(II) (237.4 mg.-1) and Cd(II) (97.9 mg.g-1) from aqueous solution at pH 5.5, agitation time 60 min and 298 K.The experimental sorption data could be fitted well with Langmuir isotherm model suggesting a monolayer adsorption behavior. Chemisorption mechanism via melaminethiourea groups grafted on the surface of activated carbon is suggested based on the excellent agreement of the kinetic data with pseudo–second-order model. The MT-MAC exhibited high stability over three adsorption-desorption cycles. The results also revealed that MT-MAC is a promising adsorbent for the extraction of Hg(II), Pb(II) and Cd(II) ions from polluted water.

The syntheses of new zinc(II), palladium(II), platinum(II) and silver(I) complexes of indol-3-acetic acid (HIAA) as a primary chelate and N,N- (2,2’-bipyridyl; bpy) or P- (triphenylphosphine; PPh3) as secondary chelate are reported. The molecular structures of these complexes are discussed based on spectral {IR, NMR (1H, 13C, 31P), UV–Vis, and EI and maldi-mass}, elemental analysis, molar conductivity and TGA measurements. HIAA coordinates the metal ions through the two O-atoms of -COO-, deprotonated O = C-O- or carbonyl O-atom (HO-C = O) in a mononegative bidentate, mononegative monodentate or neutral monodentate fashion, respectively. In case of the binuclear Ag(I) complex, HIAA behaves as mononegative bidentate ligand, binding two Ag(I) ions through both carbonyl O- and deprotonated -O- atoms. The dissociation constant (pKa) of HIAA was determined and the stoichiometry of the complexes in solution was established using the molar ratio and Job’s methods. The anticancer activity of some of the complexes was examined against the human ovarian cancer (VC-8-BRCA and VC-8) cell lines. The DNA-binding properties of the water-soluble complexes were investigated using UV-vis spectroscopy. The complexes may undergo intercalative CT-DNA binding in view of their hypochromism. The binding constants (Kb) of the complexes with CT-DNA show high-to-moderate binding abilities.HighlightNew Zn(II), Pd(II), Pt(II) and Ag(I) complexes of indole-3-acetic acid (HIAA) are reported.The structure of the complexes has been discussed based on physico-chemical measurements.In vitro anticancer activities the complexes against human ovarian cancer (VC-8-BRCA & VC-8) cell lines have been tested.DNA-binding properties of some of the complexes have been studied New Zn(II), Pd(II), Pt(II) and Ag(I) complexes of indole-3-acetic acid (HIAA) are reported. The structure of the complexes has been discussed based on physico-chemical measurements. In vitro anticancer activities the complexes against human ovarian cancer (VC-8-BRCA & VC-8) cell lines have been tested. DNA-binding properties of some of the complexes have been studied

Here, a highly sensitive and selective copper ion (Cu2+) fluorescence sensor is reported. The Hematoporphyrin functionalized Graphene Oxide (HP-GO) fluorescence sensor were synthesized via esterification reaction between Graphene Oxide and Hematoporphyrin (HP). The HP-GO sensor was fully characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), Scanning Electrom Microscopy (SEM), UV–Vis spectroscopy, Transmission Electron Microscopy (TEM), Fluor meter spectroscopy, X-Ray photoelectron spectroscopy(XPS), and Raman spectroscopy measurements. The HP-GO sensor advertised two linear regions over the range of 0–1.18 × 103 nM and 3.93 × 103 to 47.27 nM of copper (II) with detection limit of 54 nM in the aqueous solution. The selectivity of HP-GO for Cu2+ is much higher than that of other metal ions due to the presence of aza macrocyclic ring on the surface of HP-GO which has a high binding affinity with Cu2+. Additionally, the HP-GO shows wide pH viable range (pH 6–10). The effect of other metal ions on the fluorescence intensity of the HP-GO was also studied and other metal ions show a low interference response in the detection of Cu2+. HP-GO sensor manifests advantages of high reproducibility (The quenched fluorescence of HP/GO-Cu can be recovered by EDTA), attractive long term fluorescence stability (>21 days) in water, also remarkable selectivity regarding number of metal ions (Na+, K+, Ca2+, Fe3+, Fe2+, Al3+, Pb2+, Mn2+, Mg2+, Co2+, Ni2+, Cr6+, Cd2+, Hg2+, and Zn2+), low toxicity and can detect Cu2+ in real water samples which acquire well for its promising in environmental applications.

A novel chelating adsorbent, based on the chemical modification of graphene oxide by functionalization amidinothiourea to form 2-imino-4-thiobiuret-partially reduced graphene oxide (IT-PRGO), is used for the effective extraction of the toxic metal ions Hg(II), Cu(II), Pb(II), Cr(VI), and As(V) from wastewater. FTIR and Raman spectroscopy, XRD, and XPS confirm the successful incorporation of the amidinothiourea groups within the partially reduced GO nanosheets through nucleophilic substitution reactions with the acyl chloride groups in the chemically modified GO. The IT-PRGO adsorbent shows exceptional selectivity for the extraction of Hg(II) with a capacity of 624 mg/g, placing it among the top of carbon-based materials known for the high capacity of Hg(II) removal from aqueous solutions. The maximum sorption capacities for As(V), Cu(II), Cr(VI), and Pb(II) are 19.0, 37.0, 63.0, and 101.5 mg/g, respectively. The IT-PRGO displays a 100% removal of Hg(II) at concentrations up to 100 ppm with 90%, 95%, and 100% removal within 15, 30, and 90 min, respectively, at 50 ppm concentration. In a mixture of six heavy metal ions containing 10 ppm of each ion, the IT-PRGO shows a removal of 3% Zn(II), 4% Ni(II), 9% Cd(II), 21% Cu(II), 63% Pb(II), and 100% Hg(II). A monolayer adsorption behavior is suggested based on the excellent agreement of the experimental sorption isotherms with the Langmuir model. The sorption kinetics can be fitted well to a pseudo-second-order kinetic model which suggests a chemisorption mechanism via the amidinothiourea groups grafted on the reduced graphene oxide nanosheets. Desorption studies demonstrate that the IT-PRGO is easily regenerated with the desorption of the metal ions Hg(II), Cu(II), Pb(II), Cr(VI), and As(V) reaching 96%, 100%, 100%, 96%, and 100%, respectively, from their maximum sorption capacities using different eluents. The IT-PRGO is proposed as a top performing remediation adsorbent for the extraction of heavy metals from waste and polluted water.