Advanced Materials Research Vols. 233-235

Abstract: Catalytic oxidation of cyclohexane to cyclohexanone and cyclohexanol using hydrogen peroxide over ferrous sulfate catalyst at atmospheric condition was studied. Effect of the solvent volume, catalyst amount, hydrogen peroxide volume, reaction temperature, reaction time on reaction was investigated. Results showed that using 10 mL of acetone, 0.02 g of a ferrous sulfate and 0.5 mL of hydrogen peroxide at thereaction temperature of 80 °C for 8 h, the conversion of cyclohexane was 35.35%, the total selectivity of cyclohexanone and cyclohexanol was 94.06%.

Abstract: For the poor anti-pilling performance of bamboo pulp knitted fabrics, the anti-pilling finishing process of bamboo pulp knitted fabrics by cellulase was investigated in this paper. The optimal finishing conditions obtained by using the factorial and orthogonal test are concentration of cellulase 8 % (owf), pH value 5, temperature 50and time 30min. After finishing, the anti-pilling property of bamboo pulp knitted fabrics has been greatly improved with the pilling grades increased from 2 to 3, and a partial improvement of the fabric appearance and hand feeling has been also achieved.

Abstract: The residual rich SiO₂ slag was obtained for magnesium was leached from the boron mud by sulfuric acid. The SiO₂ was leached from the residual slag by sodium hydroxide solution. The effect of the leaching temperature and the leaching time, the ratio of the sodium hydroxide solution to slag and the concentration of the sodium hydroxide solution on the leaching efficiency of SiO₂ in the residual slag were also studied. The reasonable technical condition as follow : the leaching temperature is 130°C, the leaching time is 6 min, the concentration of the sodium hydroxide solution is 19mol·L^-1, the ratio of the sodium hydroxide solution to slag is 2.5:1. The SiO₂ leached rate can be stabilized about 85% under this condition. Silicon dioxide was produced by double carbonating the sodium silicate solution and its percentage purity is above 99%.

Abstract: A novel method via electroless silver coating on nickel powders was reported., which introduced reduction reaction using hydrazine as the reducing agent, had some advantages such as inhibiting the substitution reaction and reducing consumption of nickel powders. In the process of dispersion, PVP acted as the dispersant and prevented the nickel powders from agglomerating.The Zeta potential of slurry which determined the dispersibility and the reaction condition was tested.The investigation shows that the grain size of Ag-Ni bimetallic powders is similar to the nickel powders, bimetallic powders possesses fine dispersibility and a continuous silver film is formed on the surface of nickel powders by two-times coating. Morphology of Ag-Ni bimetallic powders, composition of the coated-surface are respectively characterized by SEM and EDX.

Abstract: In this paper, wool fabric was dyed by Shikonin. The optimum conditions of dyeing wool fabric with Shikonin were obtained by the orthogonal and single factor analysis experiments. The specific process conditions are as follows: liquor ratio 1:40; dye concentration 80ml/L; pH 4; temperature 80; time 60min. The results indicated that fastness to washing and to rubbing of wool fabrics dyed with Shikonin was good and has reached more than three level.

Abstract: On the basis of wholly analyzing the mechanism of the heat transfer in the regenerative heating furnace，the physical and mathematical 3-d model was set up to describe the heat transfer and combustion in the furnace. Then the CFD software was used to simulate the combusting process of the whole furnace. At last, the flow and the temperature profile in the whole furnace were deeply studied and the flow character and the temperature distribution law in the furnace were revealed in detail. The conclusions here were helpful to the reasonable design and optimization controlling of such furnaces.

Abstract: The starch is oxidized to dialdehyde starch by sodium periodate and condensed with urea to generate shrimp feed adhesive. The experimental result shows: Blend 38g starch to 150ml H₂O, concoct 15g sodium periodate to PH 1~1.5, heat it for 2 hours within 35～40°C, flush it 4 times and filter it to obtain dialdehyde starch with 15% dialdehyde; Blend the dialdehyde starch to 200ml H2O, and stir it uniformly, concoct it to PH 8.5~9 with alkali, heat it up to 95～98°C, add 7g urea first, 30 minutes’ reaction later, add another 3g urea. After1 hour’s reaction, concoct it to PH 4~5 with acid. After 1~2 hours’ polycondensation, concoct it to PH 7~8 with alkali, and a liquid adhesive is formed. The shrimp feed could be insoluble for 2 hours in water when added 1% adhesive.

Abstract: In order to reduce the silicon content to the maximum allowed value for the production of high-purity titanium dioxide, a hydrometallurgical process on the desiliconization during alkaline leaching of titanium slag under atmospheric pressure was studied. The effect of leaching temperature, initial NaOH concentration, leaching time and mass ratio of alkali to slag, on the efficiency of silicon removal were investigated. The results show that when the mass concentration of NaOH is 30%, mass ratio of alkali to slag 3:1, the leaching temperature 120°C and the retention time about 120min, the content of silicon in solid is reduced to 0.45%. Simultaneously, the content of aluminum is reduced to 1.62%, without affecting the content of titanium. The kinetics on the desiliconization during alkaline leaching of titanium slag was carried out. The results show that under the leaching parameters mentioned above, the apparent activation energy is calculated to be 45.43kJ/mol.

Abstract: The Mg(OH)₂-based peroxide bleaching process of Nigra poplar CTMP pulp was confirmed. The optimal bleaching condition were as follows: 4% H₂O₂,1% Mg(OH)₂, 15% pulp consistency, the reaction temperature was 80°C and the suitable reaction time was 2 hours. The Mg(OH)₂-based bleaching process shows significant benefits over sodium hydroxide process. In contrast, magnesium hydroxide bleaching generates higher pulp yield and lower effluent COD at the same chemical dosage. The study shows peroxide bleaching of CTMP pulp with magnesium hydroxide as alkali source is to be an option for the high-yield pulp bleaching.

Abstract: The solubility data of 2,4-dinitrotoluent (2,4-DNT) in mixed solvents of water and nitric acid with nitric acid mass fraction vary from 0.1 to 0.5 were determined at 283.15-323.15K by the equilibrium method. It indicates that the solubility increases with the increase of temperature and decreases with the decrease of mass fraction of nitric acid. The experimental data were correlated with λ-h equation, Apelblat equation and C.L.Yaws equation, average relative deviations of which between the calculated values and the experimental values of 25 data points in 5 systems were 3.666%, 2.737% and 3.121% respectively. The results show that three equations could well correlate the solubility data of 2,4-DNT in above electrolyte systems and the accuracy of the correlation can satisfy the engineering requirement.