• Journal of the Korean Ceramic Society
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• v.32 no.10
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• pp.1147-1161
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• 1995

When ceramic membrance was made from metal salt solution in place of metal akoxide solution, crack free and good adhesion to supporter was optimized for sol stability and good adhesion force. A starting sol was prepared from aluminum oxychloride aqueous solutjion in order to inhibit the grain growthof Al2O3 during heat treatment. The crack free dip coating can't be achieved in 1mol/ι zirconium oxychloride solution because of the high viscosity which interferes with the hydration copolymerization between Al3+ ion and Zr4+ ion. Thus Al2O3-ZrO2 sol stability and viscosity for dip coating was effective when 0.01 mol/ι zirconium oxychloride was added. The minimizing of crack and achieving better adhesion to the supporter wa obtained by microwave drying, surfactant addition and ultrasonic dip coating in wet atmosphere. The result seems to minimize the capillary force and improve the adhesive ability to supporter during the process. Where the average pore size of Al2O3-ZrO2 ultrafilter ceramic membrane measured 17 Å by the BET method and observed γ-Al2O3 phase with tetragonal zirconia after firing at 700℃.

• Journal of the Korean Electrochemical Society
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• v.11 no.2
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• pp.95-99
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• 2008

This study has made the electrode that is coated zirconium oxide on the titanium by ESD(Electrostatic spray deposition) coating methode. It has investigated the effects of the etching method of a Ti substrate as the preparation, making of zirconium oxide film and electrochemical characteristics of the electrode that is etched on the titanium. The HCl etching develops a fine and homogeneous roughness on the Ti substrate. Fabrication and material properties of the metal oxide electrode, which is known to be so effective to generate ozone and hypochlorous acid (HOCl) as power oxidant, were studied. A proper metal oxide material is focus zirconium oxide through reference. A coating method to enhance the fabrication reproducibility of the zirconium oxide electrode was used ESD coating method by zirconium oxychloride. Zirconium oxide films on the Ti substrate were tested using SEM, XRD, Cyclic voltammetry.

• Textile Coloration and Finishing
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• v.5 no.1
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• pp.10-18
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• 1993

Epoxy compound was synthesized from bisphellol-A with epichlorophydrine. Epoxy compound and siloxane were emulsified conjugative one or another. The water repellency of silk fabrics was also highly improved by the treatment of epoxy-siloxane mixed emulsions containing stannic chloride and zirconium oxychloride. The maximum wrinkle recovery was obtained from the fabrics treated under the condition 2.5%-epoxy-siloxane emulsion at 16$0^{\circ}C$. The breaking elongation, the reflectance, the tensile strength and the bending properties of silk fabrics were not degraded severely by the treatment of epoxy-siloxane emulsion.

• Applied Chemistry for Engineering
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• v.23 no.1
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• pp.8-13
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• 2012

The experiments have been performed to obtain zinc complex compound with smaller particle size, which is used as a charge control agent in manufacturing toner. Metallic salts and polyhydric alcohols have been studied to investigate their effects on the formation of different sizes of zinc complex-compound particle. Reactants such as zinc chloride and 3,5-di-tert-butyl salicylic acid have been used to form the complex compound. Polyethylene glycol (PEG-300), glycerin and ethylene glycol have been added into the zinc chloride solution beforehand to lower the reaction rate in the formation of zinc complex-compound. Zirconium (IV) oxychloride octahydrate has been mixed in the zinc chloride solution beforehand to restrain crystals from growing. When PEG-300 and zirconium (IV) oxychloride octahydrate are used to lower the reaction rate and to restrain the particle size from growing, the average particle size of zinc complex compound decreases from 5.28 to 1.84 ${\mu}m$, which is 34.9% of 5.28 ${\mu}m$.

• Journal of the Korean Ceramic Society
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• v.51 no.5
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• pp.466-471
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• 2014

Hydrous zirconia particles were prepared from $ZrOCl_2$ aqueous solution using an electro-dialysis [ED] process. For the preparation of $(Zr,Y)(OH)_4$ precipitates, 3 mol% $YCl_3$ was added into $ZrOCl_2$ aqueous solution. During the hydrolysis of 0.5 mol/L $(Zr,Y)OCl_2$ solution at $90^{\circ}C$ a slurry solution was obtained. The ED process was used for the removal of chlorine from the slurry solution. Two kinds of slurry solution were sampled at the beginning and end of the ED process. The morphology of hydrous zirconia particles in the solution was observed using an inverted optical microscope and an FE-SEM. The hydrous zirconia particles were nano-crystalline, and easily coagulated with drying. Yttrium stabilized zirconia [YSZ] powder could be obtained by the calcination of $(Zr,Y)(OH)_4$ precipitates prepared from a $(Zr,Y)OCl_2$ solution by the ED process. The coagulated dry powders were shaped and sintered at $1500^{\circ}C$ for 2 h. The sintered body showed a dense microstructure with uniform grain morphology.

• Bulletin of the Korean Chemical Society
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• v.26 no.11
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• pp.1749-1756
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• 2005

The $NiSO_4$ supported on FeO-promoted $ZrO_2$ catalysts were prepared by the impregnation method. FeOpromoted $ZrO_2$ was prepared by the coprecipitation method using a mixed aqueous solution of zirconium oxychloride and iron nitrate solution followed by adding an aqueous ammonia solution. The addition of nickel sulfate (or FeO) to $ZrO_2$ shifted the phase transition of $ZrO_2$ (from amorphous to tetragonal) to higher temperatures because of the interaction between nickel sulfate (or FeO) and $ZrO_2$. 10-$NiSO_4$/5-FeO-$ZrO_2$ containing 10 wt % $NiSO_4$ and 5 mol % FeO, and calcined at 500 ${^{\circ}C}$ exhibited a maximum catalytic activity for ethylene dimerization. $NiSO_4$/FeO-$ZrO_2$ catalysts was very effective for ethylene dimerization even at room temperature, but FeO-$ZrO_2$ without $NiSO_4$ did not exhibit any catalytic activity at all. The catalytic activities were correlated with the acidity of catalysts measured by the ammonia chemisorption method. The addition of FeO up to 5 mol % enhanced the acidity, surface area, thermal property, and catalytic activities of catalysts gradually, due to the interaction between FeO and $ZrO_2$ and due to consequent formation of Fe-O-Zr bond.

• Bulletin of the Korean Chemical Society
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• v.27 no.12
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• pp.1989-1996
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• 2006

The $NiSO_4/CeO_2-ZrO_2 $catalysts containing different nickel sulfate and $CeO_2$ contents were prepared by the impregnation method, where support, $CeO_2-ZrO_2$was prepared by the coprecipitation method using a mixed aqueous solution of zirconium oxychloride and cerium nitrate solution followed by adding an aqueous ammonia solution. No diffraction line of nickel sulfate was observed up to 20 wt %, indicating good dispersion of nickel sulfate on the surface of $CeO_2-ZrO_2$. The addition of nickel sulfate (or $CeO_2$) to $ZrO_2$ shifted the phase transition of $ZrO_2$ from amorphous to tetragonal to higher temperatures because of the interaction between nickel sulfate (or $CeO_2$) and $ZrO_2$. A catalyst (10-$NiSO_4/1-CeO_2-ZrO_2$) containing 10 wt % $NiSO_4$ and 1 mole % $CeO_2$, and calcined at $600{^{\circ}C}$ exhibited a maximum catalytic activity for ethylene dimerization. The catalytic activities were correlated with the acidity of catalysts measured by the ammonia chemisorption method. The role of $CeO_2$was to form a thermally stable solid solution with zirconia and consequently to give high surface area, thermal stability and acidity of the sample.

• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.1006-1014
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• 1996

A series of catalysts, $NiO-ZrO_2/WO_3$, for ethylene dimerization were prepared by coprecipitation from a solution of nickel chloride - zirconium oxychloride mixture followed by dry impregnation with an aqueous solution of ammonium metatungstate and calcination in air. On the basis of the results obtained from x-ray diffraction and DSC, the addition of NiO and $WO_3$ to $ZrO_2$ shifted the transition of $ZrO_2$ from amorphous to a tetragonal phase toward higher temperatures due to the interaction between NiO(or $WO_3$) and $ZrO_2$. $NiO-ZrO_2$ without $WO_3$ was inactive for the ethylene dimerization, but $NiO-ZrO_2/WO_3$ was found to be very active even at room temperature. The high catalytic activity of $NiO-ZrO_2/WO_3$ was closely correlated with the increase of acid strength by the inductive effect of $WO_3$.