氧化还原体系溶液进样对原子吸收火焰的增温作用

Temperature increasing effect of atomic absorption flame by redox system solution injection

研究了氧化还原体系溶液进样对原子吸收光谱法中空气-乙炔火焰的增温作用。应用双波长吸收法,首先采用镓(Ga)标准溶液进样,在不同乙炔流量、不同观察高度条件下对空气-乙炔火焰的温度进行测量,验证空气-乙炔火焰的温度分布情况,然后选定高氯酸、硝酸、无水乙醇、蔗糖4种试剂,以适当浓度、不同组合配制6种氧化还原体系介质的Ga标准溶液、使用其进样,在不同Ga标准溶液、乙炔流量与观察高度条件下进样,对空气-乙炔火焰温度进行测量,验证利用氧化还原体系介质溶液进样提高空气-乙炔火焰温度的可行性。结果表明,所选定试剂作为溶液介质进样增温空气-乙炔火焰是可行的,不同介质溶液进样对空气-乙炔火焰的增温效果有差异。根据实验数据确定了6种介质溶液进样、空气-乙炔火焰温度达到最高时的乙炔气流量和火焰观察高度,为使用空气-乙炔火焰原子吸收光谱法测定某些难熔元素如(Mo)、(Ba)、(Al)、(Sn)、(W)、(V)奠定了基础。

The temperature increasing effect of solution injection in redox system on air acetylene flame in atomic absorption spectrometry was studied.The gallium standard solution was used as the samples,the temperature of the air acetylene flame was measured with the conditions of different acetylene flow rates and different observation heights by using double wave length absorption method to verify the temperature distribution of the air acetylene flame.Then four reagents of perchloric acid,nitric acid,anhydrous ethanol and sucrose were selected to prepare Ga standard solutions of six redox system mediums with appropriate concentrations and different combinations.The air acetylene flame temperature was measured with various Ga standard solution,acetylene flow rates and observation heights to verify the feasibility of using redox system medium solution injection to improve the air acetylene flame temperature.The experimental results showed that it was feasible for the selected reagents to be used as solution medium to warm the air acetylene flame,and the temperature increasing effect of different medium solution injection on the air acetylene flame was different.At the same time,when sample injection with six medium solutions,according to the experimental data,the acetylene gas flow rate and flame observation height were determined when the air acetylene flame temperature reached the highest,which layed a foundation for future research on the determination of some refractory elements such as Mo,Ba,Al,Sn,W and V by air acetylene flame atomic absorption spectrometry.