Zinc salts of ethyl, isopropyl and butyl Xanthates were prepared in the laboratory. The effect of these Xanthates with zinc diethyldithiocarbamate (ZDC) on the vulcanization of HAF filled NR compound has been studied at different temperatures. The rubber compounds with the three Xanthate accelerators and ZDC were cured at various temperatures from 60°C–150°C. The sheets were moulded and properties such as tensile strength, tear strength, cross-link density, elongation-at-break, compression set, heat build up, abrasion resistance, flex resistance etc. were evaluated. The properties showed that zinc Xanthate/ZDC accelerator combination has positive synergistic effect on the mechanical properties of NR compounds. The curing of HAF filled NR compound containing zinc Xanthate/ZDC is slightly slower than the curing of the corresponding gum compounds. It is seen that, by gradually increasing the amount of the accelerator, the cure time of black filled NR compound can be made equal to that of the gum compound.

The effect of sulfite interaction with galena on the mechanism of potassium isoamyl Xanthate (KIAX) synthesized adsorption onto galena surfaces has been studied in situ using electrochemical potential; FTIR spectra and SEM have been used to identify the mechanism of interaction between sulfite and galena surfaces. Activated galena with copper sulfate (10-4 M) has been investigated at pH 9.12 and potassium isoamyl Xanthate (3×10-3 M) concentration. Oxidised galena surfaces have relatively low concentration of adsorbed Xanthate and high potential (Eopt=-89 mV); adsorbed colloidal (Pb-IAX, 1,123.08 cm-1) is found even at high Xanthate concentration, colloidal lead oxide/hydroxide particles have been imaged after 10-4M lead sulfate addition at pH 9.12. The behavior of this system is consistent with ion exchange between Xanthate and hydroxide followed by oxidation to dixanthogen (X2, 1,273.56 cm-1) and diffusion of this species across the surface.

Copper oxide minerals such as malachite do not respond well to the traditional copper sulfide collectors, and require alternative flotation schemes. In many copper ore mines, significant copper oxide minerals, especially malachite, are associated with sulfide minerals. Considering that Xanthates are most widely used in the flotation of sulfide minerals as well as copper sulfide minerals and, hydroxamate has shown a good selectivity for copper oxide minerals. Use of the synergistic effect of Xanthate and hydroxamate can be an effective way to increase the flotation efficiency of copper oxide minerals along with sulfide minerals. In this work, we investigate the individual interactions of potassium amyl Xanthate (PAX) and potassium alkyl hydroxamate (HXM) with the natural malachite and explore their synergistic effects on the malachite flotation. The results of solubility of malachite in collector solutions, changes in the malachite surface potential, adsorption kinetics, adsorption densities, dynamic contact angles, FT-IR analyses, and small-scale flotations, are discussed. The results obtained demonstrate that PAX and HXM are chemically co-adsorbed on the malachite surface, and the amount of PAX adsorbed on the malachite surface is considerably increased in the mixed PAX/HXM systems because of the co-adsorption mechanism. The flotation results confirm that the mixed PAX/HXM exhibit a superior flotation performance of malachite compared to the individual system of PAX or HXM. Based on these results, the mixed PAX/HXM exhibit a remarkable synergism effect on malachite surface hydrophobicity.

In this study, we suggest proceeding to an experimental study concerning the synthesis of new organo metallic product Xanthate (KIBX) by intermittent method and their use in the processes of sulphides flotation.The adsorption of potassium isobutyl Xanthate (KIBX 3⋅10-3M) on sphalerite has been studied using electrochemical potential, FTIR technique and SEM. Non activated minerals and minerals activated with copper sulfate (10-4 M) and copper nitrate (10-4 M) have been investigated at pH 7.5. Surface species have been identified by FTIR and correlated with SEM. After copper sulfate activation, copper Xanthate exists on all of the minerals studied.Neutral pH is the most suitable for potassium isobutyl Xanthate adsorption on sphalerite.

BACKGROUND AND OBJECTIVES: The increase in industrial effluent discharges from sectors such as smelting, electroplating, pharmaceuticals, and ceramics has led to a rise in heavy metal presence in ecosystems, posing a growing environmental risk. In the search for increasingly efficient materials, there has been growing interest in using adsorbents derived from both biological sources and industrial waste, due to their low cost, availability, and effectiveness in removing heavy metals from aqueous environments. The objective of this study was to assess the potential of a modified adsorbent resin, synthesized from mineral coal waste originating in Cesar, Colombia, for the removal of cadmium and lead from aqueous solutions as a sustainable remediation strategy.METHODS: The coal waste was chemically modified using sodium hydroxide and carbon disulfide to synthesize the adsorbent resin. Batch adsorption experiments were conducted at potential of hydrogen levels ranging from 3 to 8 to evaluate the removal performance. The influence of potential of hydrogen on adsorption efficiency was investigated, and the experimental data were subjected to a comparative modeling approach. Adsorption equilibrium was assessed using the Freundlich, Langmuir, and Langmuir–Freundlich isotherms, while kinetic behavior was interpreted through pseudo-first- and second-order models.FINDINGS: The results demonstrated that the removal efficiencies varied with potential of hydrogen, reaching maximum values when it was adjusted to 6, with 98 percent for lead and 97 percent for cadmium. The adsorption process followed the Freundlich isotherm, suggesting a multilayer adsorption mechanism, and the pseudo-second-order kinetics indicated that chemisorption was the dominant mechanism.CONCLUSION: This study highlighted the potential of modified mineral coal waste as an effective adsorbent for the removal of cadmium and lead, offering a promising alternative for the treatment of industrial wastewater. In addition to its high performance, this strategy contributes to the valorization of solid waste from coal mining, promoting a circular economy and reducing the environmental impact associated with its disposal.

For the first time formation of well-defined poly n-vinylpyrrolidone/n-TiO2 nanocomposite by Xanthate-mediated radical polymerization was accomplished. The synthesis of polymer nanocomposite materials has been intensively studied due to their extraordinary properties and wide-spread potential applications. For this purpose, first 2‐, propionic acid-O-ethyl Xanthate, as a RAFT agent, was synthesized by the reaction of 2-bromopropionic acid with potassium O-ethyl Xanthate with acetone as the solvent. A carboxylic group in the RAFT agent was attached to the n-TiO2 surface by metalation reaction. Then, RAFT polymerization of n-vinylpyrrolidone (NVP) was subsequently conducted to graft poly(n-vinylpyrrolidone) (PNVP) onto the exterior surface of n-TiO2 nanoparticles, forming a novel core–, shell nanostructure with a mesoporous core and a polymeric nanoshell. The viscosimetry data and 1H NMR spectra were used to calculate the molecular weight of the polymer. The obtained results showed a good agreement withthe methods used. A significant enhancement in the stability of the composites was obtained as demonstrated by the TGA results. The SEM and TEM results showed that the polymer was formed on the surface of the particles. The XRD pattern of the nanoparticles of n-TiO2 presented the amorphous structure of the crystal morphology of the composites. The FTIR and UV–, visible spectroscopy results proved that the PNVP chains were grafted onto the n-TiO2 nanoparticles by surface RAFT polymerization.

Three iso-alkyldithiocarbonates (Xanthates), as sodium salts, C3H7OCS2Na (I), C4H9OCS2Na (II) and C5H11OCS2Na (III) were synthesized, by the reaction between CS2 and the corresponding iso-alcohol in the presence of NaOH. These compounds were examined for inhibition of cresolase activity of mushroom tyrosinase (MT) from a commercial source of Agricus bisporus.4- [(4-methylphenyl) azo] -phenol (MePAPh) were used as synthetic substrate for the enzyme for the cresolase reaction. Lineweaver-Burk plots showed different patterns of mixed and competitive inhibition for the three Xanthates. For cresolase activity, I and II showed a mixed inhibition pattern but III showed a competitive inhibition pattern. These new synthesized compounds are potent inhibitors of MT with Ki values of 9.8, 7.2 and 6.1 microM for cresolase inhibitory activity, for compound-I, -compound-II and compound-III, respectively. Both substrate and inhibitor can be bound to the enzyme with negative cooperativity between the binding sites (a>1) and this negative cooperativity increases with increasing length of the aliphatic tail in these compounds in cresolase activity. The cresolase inhibition is related to the chelating of the copper ions at the active site by a negative head group (S-) of the anion Xanthate, which leads to similar values of Ki for all three Xanthates.

In the present study, the aim is to synthesize and introduce the combination of methoxy amido Xanthate MAX and then label it with 99mTc radionuclide as a novel diagnostic agent for single-photon computed tomography (SPECT) imaging. A chelator-designed ligand was synthesized from a blend of chloroacetamide and Xanthate in certain proportions. After that MAX ligand labeling process was performed by directly milking 99mTc from the generator (99Mo / 99mTc). Thus, tin chloride was employed as a reducing agent, and the effect of parameters such as additives like ascorbic acid, changing the concentration of the cheating agent, and pH were evaluated to optimize the labeling conditions. The product was then identified by infrared spectroscopy (FTIR) and magnetic resonance imaging (NMR). Labeling of the complex at laboratory temperature was determined to be 93%. The new 99mTc-MAX radiopharmaceutical with a radionuclide and radiochemical purity of over 90% can be used as an encouraging diagnostic agent in clinics and preclinical studies, which will be addressed in future studies.

Seven reported Xanthate ligands and their new Fe (II) complexes of formulaNa [Fe (R-OCSS)3], where R is ethyl-, propyl-, butyl-, pentyl-, Hexyl-, heptyl- and octyl-Xanthate have been synthesized.They have been characterized using elemental analysis, molar conductance, FT-IR, UV-Vis and 1H NMR spectroscopic techniques and melting-, decomposition-points for ligands and complexes respectively. All the ligands and their Fe (II) complexes have been evaluated for their antimicrobial activity against four gram-positive bacteria, four gram-negative bacteria and three fungi by agar disc diffusion technique. The MIC values of the compounds exhibited significant antifungal activity but showed lower antibacterial activity. The iron (II) complexes are found to possess higher antimicrobial activity than their counterpart ligands thus improving its antimicrobial efficacy.Hydrocarbon chain length of the ligands coordinated to Fe (II) centers seemed to be important for their antifungal as well as antibacterial activities.

Corn stalk can be used as a potential adsorbent because of its abundance, cost-effectiveness, and accessible functional groups that allow chemical modifications. This study aims to synthesize cellulose Xanthate alginate beads (ACX beads) from corn stalks to remove methylene blue from aqueous solutions. ACX beads with various doses of porogen CaCO3 were printed using the ionic gelation method, and then characterized using FTIR, optical microscopy, and SEM-EDX. The results of the FTIR analysis reported changes in the C-S, C=S, and S-C-S vibrations that indicated the Xanthate formation. Furthermore, as the porogen dose increased, the OH intensity decreased. The high intensity of the OH group results in a high swelling process. The results of the optical microscopy analysis showed that the porogen made the ACX beads spherical. SEM-EDX analysis showed that the higher the porogen dose, the rougher the surface morphology of the ACX beads and the larger the pore diameter. The maximum adsorption capacity was obtained on ACX beads without porogen with a contact time of 360 hours. The study reveals that the kinetic adsorption followed a pseudo-second-order kinetic model proposed chemical adsorption. The larger the porogen, the more crosslinks between the divalent cations and alginate or cellulose that are formed, inhibiting the bond between the ACX beads and water and methylene blue, thereby reducing the swelling process and the adsorption capacity of the ACX beads. In addition, the pore size that is too large does not match the size of the methylene blue molecule.