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Incorporation of nicotinamide and tartrate mixed ligand into Co(II) coordination polymer as functional porous materials is being studied. Initial attempt by layered solution technique in water-methanol solvent system with excess amount of nicotinamide resulting in Co(II)-tartrate complex only. Other method to obtain the targeted complex of Co(II)-tartrate-nicotinamide or CoTN by direct mix technique using dimethylformamide as solvent is proposed in this paper. The reactions were performed at 80 °C in Co(II):T:N molar ratios of 1:1:2 and 1:1:4 and using several Co(II) salts, namely chloride, acetate, and nitrate. All precipitated products were characterized by infrared spectroscopy and melting point test. Experimental data shows that the proposed reaction recipes did not successfully produce the targeted Co(II)TN complex, which presumably due to the reaction may needs higher temperature and/or pressure. Thus, solvothermal method is recommended for the next attempt. Interestingly, the use of different salt of Co(II) lead to different products, which is never been reported before. Pale purple complex of Co(II)-nicotinamide was yielded from the chloride salt, whereas complexes of Co(II)-tartrate was produced from the acetate and the nitrate salts. Melting point test suggests that the Co(II)-tartrate obtained from the acetate salt is different to that of the nitrate salts. This tartrate vs nicotinamide ligand preference within the same type of metal center, due to the use of different anion of the Co(II) salt, is unprecedented and still being investigated. [ABSTRACT FROM AUTHOR]

Kaoline is one of natural clays. This layered mineral can be delaminated, i.e separation of layers of kaoline each other. To achieve the purpose, kaoline can be grafted or intercalated. In this research, kaoline was treated by both combination. Sequaence of treatments (intercalation - grafting and grafting - intercalation) were studied in this research. Propanol and sodium dodesyl benzene sulphonate (SDBS) surrfactant were used for grafting and intercalation process, respectively. Before those treatments, activation of kaoline was performed by stirring of kaoline in H2SO4 solution (0.1M). The activated kaoline was intercalated by SDBS solution (0.1M) statically followed by under stirring, then grafted by propanol statically followed by under stirring. The opposite treatment was the grafting by propanol statically followed by under stirring, then intercalated statically followed by under stirring. Characterization using FTIR spectrometry shows that the grafting treatment gave no significant difference, but intercalation treatment gave significant changing of FTIR spectra, especially related to C-H bond vibration, connected to surfactant. SEM characterization confirmed that the treatment of the intercalation - grafting provided more delaminated kaoline than the grafting - intercalation. [ABSTRACT FROM AUTHOR]

Pesticide contamination is one of earth crust problems, especially for agriculture soil. Addition of nanocarbon into liquid fertilizer is solution to remediate the polluted paddy field by adsorption and natural microbial degradation. Nano size of the carbon was conditionized by formation of dispersion system. The colloid system is needed to guarantee that the carbon can be used as part of fertilizer liquid to spray easily in the paddy field. Modification of nanocarbon using catalyst ZnO can improve catalytic degradation reaction of pesticide in agriculture soil. In this research, the nanocarbon was prepared from rice husk using hydrothermal - microwave and reflux - microwave. Purpose of this research is to study influence of both pyrolisis methods toward physical and chemical properties of nanocarbon. The pyrolisis process was performed by hydrothermal process (200°C, 5 h) or reflux process (200°C, 6 h) and followed by microwave process (800 W, 40 minutes). Weight ratio of the rice husk (> 60 mesh) and ZnCl2 as carbon activator is 50:1. No removal of ZnO after pyrolisis so that the products were ZnO - carbon composites. Nano size of the products were conditionized by formation of colloid system using each blending and stirring technique for 1 h. Chemical analysis of the rice husk was conducted by public analysis service in Department of Chemistry Brawijaya University. Result of the research showed that the rice husk contains in sequence of celulose>hemicellulose>lignin. The hydrothermal - microwave pyrolisis provided the darker product than the reflux - microwave method. FTIR spectra of the products showed that the pyrolized biomass had less both -OH and aliphatic -CH functional groups than the biomass. The double pyrolisis methods have produced the nanocarbons which have lower content of -OH and aliphatic -CH functional groups, but more M-O than the individual method. X-ray diffractograms of the composites had the patterns similar to CNT and nanocellulose difrractograms. The celulose crystalinity indexes of the composites are lower than of the biomass, indicating structure transformation of cellulose to the carbon structure. SEM images showed that the nanocomposite prepared by hydrothermal - microwave method has smaller particles than the reflux - microwave. Colloid system of the nanocomposite was more effectively formed by blending than stirring technique. UV - Vis spectra showed that the colloid of nanocarbon synthesized by hydrothermal - microwave methods had 2 peaks at 281.5 and 254 nm, otherwise by reflux - microwave provided one peak at 279 nm. [ABSTRACT FROM AUTHOR]