The species of arsenic in secondary zinc oxide generated from fuming furnace were investigated. The results revealed that there are mainly three types of secondary zinc oxide based on three arsenic species. The main p...The species of arsenic in secondary zinc oxide generated from fuming furnace were investigated. The results revealed that there are mainly three types of secondary zinc oxide based on three arsenic species. The main phase of As is As2O3 in type Ⅰ, zinc arsenite （Zn（AsO2）2） in type Ⅱ and lead arsenate （Pb（As206）, Pb4As2O9） in type Ⅲ, respectively. Selective leaching of zinc oxide of type Ⅱ was carried out. The leaching rate of As kept at 65%-70% with 30 g/L NaOH and L/S ratio of 3 at 20 ℃ for 1 h, while the losses of Pb and Zn were both below 1%.展开更多
The feasibility of a new method for separating arsenic from arsenic-antimony-bearing dusts using Cu S was put forward,in which Sb was transformed into Sb2O4 and Sb2S3 that stayed in the roasted calcine while As was vo...The feasibility of a new method for separating arsenic from arsenic-antimony-bearing dusts using Cu S was put forward,in which Sb was transformed into Sb2O4 and Sb2S3 that stayed in the roasted calcine while As was volatilized in the form of As4O6.The factors such as roasting temperature and Cu S addition amount were studied using XRD,EPMA and SEM-EDS.Cu S has an active effect on the separation of arsenic due to the destruction of(Sb,As)2 O3 structures in the original dust and the simultaneous release of As in the form of As4O6.At a roasting temperature of 400°C and Cu S addition amount of 130%,the volatilization rates of arsenic and antimony reach 97.80 wt.%and 8.29 wt.%,respectively.Further,the high As volatile matter can be used to prepare ferric arsenate after it is oxidized,with this treatment rendering the vapor harmlessness.展开更多
The purpose of this procedure was to optimize and improve a method that used for the determination of arsenic （Ⅲ） and arsenic （Ⅴ） in biological and environmental samples. The method is based on hydride generatio...The purpose of this procedure was to optimize and improve a method that used for the determination of arsenic （Ⅲ） and arsenic （Ⅴ） in biological and environmental samples. The method is based on hydride generation and atomic absorption spectrometry. For both As （Ⅲ） and As （Ⅴ） the parameters such as NaBH4, HCI concentration, and pH were optimized. Absorption signal of As （Ⅴ） was approximately 17% of As （Ⅲ） signal. Therefore, for estimation of As （Ⅲ） and As （Ⅴ） concentrations in various samples the difference between the absorbance obtained for arsenic, without and with previous treatment of samples with potassium iodide （KI）, can be applied. The calibration graphs were linear （r〉0.99）, and the detection limits of the method based on three times the standard deviation of the blank were 0.14 and 0.64 μL^-1 for As （Ⅲ） and As （Ⅴ）, respectively. The relative standard deviation （R.S.D.） of measurements was less than 10%. As a means of checking performance method, water samples were spiked with known concentrations of both As （Ⅲ） and As （Ⅴ）, and recovery above 94% was obtained. The proposed method was applied successfully to determine inorganic As （Ⅲ） and As （Ⅴ） in various environmental and total As in biological samples.展开更多
基金Project (50874121) supported by the National Natural Science Foundation of China
文摘The species of arsenic in secondary zinc oxide generated from fuming furnace were investigated. The results revealed that there are mainly three types of secondary zinc oxide based on three arsenic species. The main phase of As is As2O3 in type Ⅰ, zinc arsenite （Zn（AsO2）2） in type Ⅱ and lead arsenate （Pb（As206）, Pb4As2O9） in type Ⅲ, respectively. Selective leaching of zinc oxide of type Ⅱ was carried out. The leaching rate of As kept at 65%-70% with 30 g/L NaOH and L/S ratio of 3 at 20 ℃ for 1 h, while the losses of Pb and Zn were both below 1%.
基金Project(51564034)supported by the National Natural Science Foundation for Distinguished Regional Scholars,ChinaProject(2015HA019)supported by the Scientific and Technological Leading Talent Program in Yunnan Province,China.
文摘The feasibility of a new method for separating arsenic from arsenic-antimony-bearing dusts using Cu S was put forward,in which Sb was transformed into Sb2O4 and Sb2S3 that stayed in the roasted calcine while As was volatilized in the form of As4O6.The factors such as roasting temperature and Cu S addition amount were studied using XRD,EPMA and SEM-EDS.Cu S has an active effect on the separation of arsenic due to the destruction of(Sb,As)2 O3 structures in the original dust and the simultaneous release of As in the form of As4O6.At a roasting temperature of 400°C and Cu S addition amount of 130%,the volatilization rates of arsenic and antimony reach 97.80 wt.%and 8.29 wt.%,respectively.Further,the high As volatile matter can be used to prepare ferric arsenate after it is oxidized,with this treatment rendering the vapor harmlessness.
文摘The purpose of this procedure was to optimize and improve a method that used for the determination of arsenic （Ⅲ） and arsenic （Ⅴ） in biological and environmental samples. The method is based on hydride generation and atomic absorption spectrometry. For both As （Ⅲ） and As （Ⅴ） the parameters such as NaBH4, HCI concentration, and pH were optimized. Absorption signal of As （Ⅴ） was approximately 17% of As （Ⅲ） signal. Therefore, for estimation of As （Ⅲ） and As （Ⅴ） concentrations in various samples the difference between the absorbance obtained for arsenic, without and with previous treatment of samples with potassium iodide （KI）, can be applied. The calibration graphs were linear （r〉0.99）, and the detection limits of the method based on three times the standard deviation of the blank were 0.14 and 0.64 μL^-1 for As （Ⅲ） and As （Ⅴ）, respectively. The relative standard deviation （R.S.D.） of measurements was less than 10%. As a means of checking performance method, water samples were spiked with known concentrations of both As （Ⅲ） and As （Ⅴ）, and recovery above 94% was obtained. The proposed method was applied successfully to determine inorganic As （Ⅲ） and As （Ⅴ） in various environmental and total As in biological samples.
