http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Zinc ferrite 의 수소 환원에 관한 연구 (1)
박평주 대한금속재료학회(대한금속학회) 1972 대한금속·재료학회지 Vol.10 No.1
Zinc ferrite의 還元 過程을 究明하기 爲하여 zinc ferrite를 水素로 還元시키고, 이때 還元되는 量은 thermal balance로 測定하였다. zinc ferrite는 700∼900℃ 수소압력 30∼55×10^(-3)mmHg 일 때 처음에는 다음과 같이 Fe₃O₄와 Zn(g)로 還元된다. 3ZnFe₂O₄+4H₂=2Fe₃O₄+3Zn+4H₂O. 이 還元反應에 要하는 活性化 energy는 17.4㎉/㏖이다. zinc ferrite를 眞空中에서(10^(-4)mmHg) 700∼950℃로 維持하며 熱分解시키면 Fe₃O₄와 Zn(g)로 分解된다. 이 分解反應이 zinc ferrite還元時의 律速反應이라고 生覺된다. Synthetic zinc ferrite was reduced with hydrogen by the use of thermal balance, in order to understand the course of the reduction. At the initiation of the reaction, zinc ferrite is reduced to Fe₃O₄ and Zn(g) as following equation at 700-900℃ and under 30∼55×10^(-3)mmHg of hydrogen pressure. 3ZnFe₂O₄+4H₂=2Fe₃O₄+3Zn+4H₂O. Activation energy associated with the reaction was determined to be 17.4㎉/㏖. Zinc ferrite decomposes to Fe₃O₄ and Zn(g) at 700∼950℃ under the pressure of 10^(-4)mmHg. And this decomposition process is considered to be a predominant factor in the reduction of zinc ferrite.
박평주,이응조 대한금속재료학회(대한금속학회) 1966 대한금속·재료학회지 Vol.4 No.2
The reduction of synthetic zinc-ferrite and pure zinc oxide pellets in a stream of 20% H₂and 80% N₂were studied at temperature from 900℃ to 1100℃. The result of the study leads to the conclusion that the reduction rate of ZnO in the zinc-ferrite is slower in the first stage and faster in the second stage than that of pure ZnO. The lagging of the reduction rate of ZnO in the zinc-ferrite in the first stage is caused by the result that almost no reduction of ZnO takes place until iron oxide has been completely reduced to Fe. At temperature of 1100℃, the reduction rate of ZnO in the zinc-ferrite was nearly as high as that of pure ZnO. In this experiment, the activation energy for reduction of pure zinc oxide by H₂gas was 26.8 kcal.
Zn-Pb alloy dust 와 Sb2O3 에 의한 황산아연액 중 Co2+ 의 제법에 관한 연구
박평주,이강능 대한금속재료학회(대한금속학회) 1982 대한금속·재료학회지 Vol.20 No.7
Co^(2+) ion in zinc electrolyte is deterious to the electrowinning of zinc. for it lowers the current efficiency of the electrolyte; therefore it should be removed until it's concentration becomes tower than 1㎎/ℓ. In this experiment, a study on the precipitation of Co^(2+) ion in zinc electrolyte was carried out by using Zn-Pb alloy dust and Sb₂O₃as additives. Co^(2+) ion is precipitated by electrochemical reaction mechanism; Sb₂O₃plays an important role by acting as anodes after it is precipitated as Sb on the surface of Zn-Pb alloy dust while Zn acts as cathodes, and Pb lowers the resolving-rate of the precipitated Co. In these experiments the optimum condition of the reaction is as follows ; stirring speed : 250 rpm. temperature : 95℃, Pb content in Zn-Pb alloy dust : 1.35%, amount of Zn-Pb alloy dust : 3g/ℓ, amount of Sb₂O₃: 5㎎/ℓ, pH ; 4, and at the optimum condition, Co^(2+) ion concentration is lowered from 30㎎/ℓ to 0.2㎎/ℓ after two hours of reaction.
Zinc ferrite 의 수소환원에 관한 연구 (2)
박평주 대한금속재료학회(대한금속학회) 1972 대한금속·재료학회지 Vol.10 No.2
Zinc ferrite를 水素로 還元시킬 때의 還元反應機構를 알기 위하여 우선 Zinc ferrite를 眞空중에서 熱分解시켜 본 다음 熱天秤을 使用하여 溫度와 水素壓力을 變化시켜 주며 還元 實驗을 하였다. 이 結果들은 酸化亞鉛 및 酸化鐵의 還元結果와 比較하였다. Zinc ferrite는 高溫 眞空中에서 쉽게 分解하여 亞鉛蒸氣와 Fe₃O₄로 된다. 또 이 眞空중으로 水素를 流入시키면 이 反應은 促進되고 이때 生成되는 Fe₃O₄는 FeO를 거쳐 金屬 鐵로 還元된다. Zinc ferrite의 還元初期단계에서의 還元 反應速度는 다음과 같이 나타낼 수 있다. 1-(1-Y)^(1/3)=K_0·P^(0.92)_(H2) t/ρ·r_0 또 Zinc ferrite의 熱分解와 水素還元에 要하는 活性化에너지는 각각 22 ㎉/㏖과 17.2∼17.4 ㎉/㏖ 이었다. In order to evaluate the reaction kinetics of zinc ferrites reduced by hydrogen, the studies were made on the thermal decomposition of synthetic zinc ferrites in vacuum and on the process of hydrogen reduction at various temperatures and pressures by thermal balance method, so that the parameters of the equation of reducing processes were determined. The results were discussed with the comparison of the rate of zinc and iron oxides. Zinc ferrites were easily decomposed into gaseous zinc and solid magnetite in vacuum at elevated temperatures, then by introduction of hydrogen to the vacuum, the decomposition was followed with the reduction of magnetite into the ferrous oxide, and finally the reaction completed by the formation of metallic iron. The rate of reduction of zinc ferrite at the initial stage may be expressed as follows: 1-(1-Y)^(1/3)=K_0P^(0.92)_(H2) t/ρ·r_0 The activation energies were calculated as 22 ㎉/㏖ for the thermal decomposition, and 17.2 to 17.4 ㎉/㏖ for the hydrogen reduction, respectively.
유동배소로상의 소결융착에 미치는 아연정광중의 Pb, Cu 의 영향에 관한 연구
박평주,백귀종 대한금속재료학회(대한금속학회) 1984 대한금속·재료학회지 Vol.22 No.11
A study on the effect of Pb and Cu in zinc ore is executed for a preventive measures of the fluidized bed agglomeration during the roasting of zinc concentrate. The more the contents of Pb and Cu in zinc concentrate increase, the more the amount of agglomeration increases. Especially, when the contents of Cu in zinc concentrate is over 2.5wt%, the roasting process is very hard. The more the roasting temperature increase, the more the amount cf agglomeration increases during the roasting of the concentrate (Pb 1.5%, Cu 0.7%), and the sorts of compound in agglomerating calcine get to be different. Namely, at 850-950℃, the agglomerating calcine contains ZnO, ZnO·Fe₂O₃,CuSO₄, 2PbO·PbSO₄4PbO·PbSO₄and 2PbO·SiO₂, etc.. At 800℃, 4PbO·PbSO₄is not contained, but at 750℃, ZnO, ZnO·Fe₂O₃, CuSO₄and PbSO₄are contained. When air blowing increases, the agglomeration decreases. In the effect for the change of particle size, when the size decreases, wt.% of bed agglomerating calcine decreases. In these experimental results for the preventive measures of the fluidized bed agglomeration, Pb and Cu in zinc concentrate must decrease less than 0.5%, 0.2% respectively, and air blowing must occasionally increase.