The thermal decomposition process ofjarosite residue and the solubility of various oxides presented in the decomposed residue in NH4C1-H20 system were studied. The results of heat decomposition ofjarosite residue show...The thermal decomposition process ofjarosite residue and the solubility of various oxides presented in the decomposed residue in NH4C1-H20 system were studied. The results of heat decomposition ofjarosite residue show that the insoluble ZnFe2O4 phase in the residue can be decomposed at temperatures ranging from 500 ℃ to 650 ℃ for 1 h. The OLI Systems software was used to study the thermodynamics of the solubility of various metal oxides existing in the decomposed residue in NH4CI-H20 system. The results show that the solubility ofZnO, PbO, CdO, CuO and Ag20 is high, while the solubility of Fe203 is less than 10-4 mol/L in the pH range from 4.0 to 9.0. The calculated data are in accordance with the experimental results.展开更多
The interaction of poly(ethylene oxide)(PEO)with the ionic surfactants,sodium dodecylsulfate(SDS)and cetyltrimethylammonium chloride(CTAC)respectively,in aqueous solutions containing a certain concentration of NH_4Cl,...The interaction of poly(ethylene oxide)(PEO)with the ionic surfactants,sodium dodecylsulfate(SDS)and cetyltrimethylammonium chloride(CTAC)respectively,in aqueous solutions containing a certain concentration of NH_4Cl, is studied by the viscosity measurement.It has been found that the ion-dipole interaction between PEO and ionic surfactants is changed considerably by the organic salt.For anionic suffactant of SDS,the addition of NH_4Cl into solution strengthens the interaction between PEO and the headgroup o...展开更多
Influence of NH_4 Cl on the initial atmospheric corrosion of zinc was investigated viaquartz crystal microbalance (QCM) in laboratory at 80%RH and 25℃. The resultsshow that NH_4 Cl can accelerate the initial corrosio...Influence of NH_4 Cl on the initial atmospheric corrosion of zinc was investigated viaquartz crystal microbalance (QCM) in laboratory at 80%RH and 25℃. The resultsshow that NH_4 Cl can accelerate the initial corrosion of zinc. Mass gain increase withthe exposure time, but mass gain in the later doesn't change obviously due to theformation of the insoluble simonkolleite on zinc surface in the presence of NH_4 Cl.Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) wasused to characterize the corrosion products. Zn_5Cl_2(OH)_8·H_2O,(NH_4)_2ZnCl_4 andZnO are the corrosion products on zinc. Brief discussion on the mechanisms of at-mospheric corrosion of zinc in the presence of NH_4 Cl was introduced.展开更多
The thermodynamic analysis of the reaction between the main phase in magnesium slag and NH_(4)Cl solutions was carried out,and the ions leaching behaviors of Ca,Mg,Fe,and Al in magnesium slag under room temperature an...The thermodynamic analysis of the reaction between the main phase in magnesium slag and NH_(4)Cl solutions was carried out,and the ions leaching behaviors of Ca,Mg,Fe,and Al in magnesium slag under room temperature and microwave conditions were compared.Meanwhile,the effects of parameters on the leaching rate of Ca and Mg were investigated under the microwave heating conditions.The experimental results show that,in 273.15-373.15 K,Ca_(2)SiO_(4),CaSiO_(3),Ca_(2)Fe_(2)O_(5),and Mg_(2)SiO_(4)might react with NH_(4)Cl solution,while MgSiO_(3),MgO,Fe_(2)O_(3),and Al_(2)O_(3)are difficult to be leached.The leaching rates of Ca and Mg are 70.29%and 24.64%,respectively,when the conditions are 300 W of microwave power,1:20 of solid-liquid ratio,400 mL of 2 mol/L NH_(4)Cl solutions,and 90 min of leaching time.In addition,in the non-isothermal stage,the leaching process of Ca is changed from chemical reaction control to diffusion control,and the leaching rate of Ca gradually increases.However,the leaching process of Mg is always controlled by chemical reaction,and the leaching rate of Mg remains unchanged after the reaction reached equilibrium.展开更多
基金Project(51090385) supported by the National Natural Science Foundation of China
文摘The thermal decomposition process ofjarosite residue and the solubility of various oxides presented in the decomposed residue in NH4C1-H20 system were studied. The results of heat decomposition ofjarosite residue show that the insoluble ZnFe2O4 phase in the residue can be decomposed at temperatures ranging from 500 ℃ to 650 ℃ for 1 h. The OLI Systems software was used to study the thermodynamics of the solubility of various metal oxides existing in the decomposed residue in NH4CI-H20 system. The results show that the solubility ofZnO, PbO, CdO, CuO and Ag20 is high, while the solubility of Fe203 is less than 10-4 mol/L in the pH range from 4.0 to 9.0. The calculated data are in accordance with the experimental results.
文摘The interaction of poly(ethylene oxide)(PEO)with the ionic surfactants,sodium dodecylsulfate(SDS)and cetyltrimethylammonium chloride(CTAC)respectively,in aqueous solutions containing a certain concentration of NH_4Cl, is studied by the viscosity measurement.It has been found that the ion-dipole interaction between PEO and ionic surfactants is changed considerably by the organic salt.For anionic suffactant of SDS,the addition of NH_4Cl into solution strengthens the interaction between PEO and the headgroup o...
文摘Influence of NH_4 Cl on the initial atmospheric corrosion of zinc was investigated viaquartz crystal microbalance (QCM) in laboratory at 80%RH and 25℃. The resultsshow that NH_4 Cl can accelerate the initial corrosion of zinc. Mass gain increase withthe exposure time, but mass gain in the later doesn't change obviously due to theformation of the insoluble simonkolleite on zinc surface in the presence of NH_4 Cl.Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) wasused to characterize the corrosion products. Zn_5Cl_2(OH)_8·H_2O,(NH_4)_2ZnCl_4 andZnO are the corrosion products on zinc. Brief discussion on the mechanisms of at-mospheric corrosion of zinc in the presence of NH_4 Cl was introduced.
基金Funded by the National Key Research and Development Program of China(No.2023YFC2908002)。
文摘The thermodynamic analysis of the reaction between the main phase in magnesium slag and NH_(4)Cl solutions was carried out,and the ions leaching behaviors of Ca,Mg,Fe,and Al in magnesium slag under room temperature and microwave conditions were compared.Meanwhile,the effects of parameters on the leaching rate of Ca and Mg were investigated under the microwave heating conditions.The experimental results show that,in 273.15-373.15 K,Ca_(2)SiO_(4),CaSiO_(3),Ca_(2)Fe_(2)O_(5),and Mg_(2)SiO_(4)might react with NH_(4)Cl solution,while MgSiO_(3),MgO,Fe_(2)O_(3),and Al_(2)O_(3)are difficult to be leached.The leaching rates of Ca and Mg are 70.29%and 24.64%,respectively,when the conditions are 300 W of microwave power,1:20 of solid-liquid ratio,400 mL of 2 mol/L NH_(4)Cl solutions,and 90 min of leaching time.In addition,in the non-isothermal stage,the leaching process of Ca is changed from chemical reaction control to diffusion control,and the leaching rate of Ca gradually increases.However,the leaching process of Mg is always controlled by chemical reaction,and the leaching rate of Mg remains unchanged after the reaction reached equilibrium.
