【摘要】 当前,拉曼光谱通常被应用于定性研究,拉曼光谱的定量研究明显不足。通过理论分析,拉曼光谱的定量研究应当基于其相对强度来进行。据此,通过对三种不同浓度的Na2SO4溶液进行拉曼光谱分析,得到了常温常压下水溶液中SO2-4离子浓度的定量方程为:c(SO2-4)=4.779 6R(r2=0.999 4)。此外,对高温高压下硫酸根水溶液的拉曼光谱也进行了研究。光谱分析表明,温度和压力将影响拉曼谱峰强度比值与SO2-4浓度的关系。高温高压下水溶液中SO2-4浓度的定量方程为:c(SO2-4)=4.779 6(R+1.469×10-4ΔT+1.340×10-4ΔP),式中c(SO2-4)为待测溶液中SO2-4的浓度,R为拉曼谱峰强度的比值R(SO2-4/H2O),ΔT为相对于常温(23℃)时的温度差,ΔP为相对于常压(0.1MPa)时的压力差。该方程适用的温度范围为23℃≤T≤360℃,浓度范围为0.5~1.5mol·L-1,测量的相对误差为6.5%。对于具有拉曼活性的物质,拉曼光谱实验技术可以用来进行水溶液中物质浓度的定量研究。更多还原

【Abstract】 In the present work,the Raman spectra of SO2-4ions in aqueous solutions were studied.The quantitative analysis shows that there is a significant correlation between the Raman intensity ratio(R)and the SO2-4concentration.The SO2-4concentration in aqueous solution at ambient temperature and pressure can be determined by the Raman intensity according to the linear fitting equation c(SO2-4)=4.779 6R(r2=0.999 4).Furthermore,the research proves that the temperature and pressure will affect the relationship between the Raman intensity ratio and the concentration of SO2-4ions.The quantitative equation for measuring the SO2-4concentration in aqueous solution at high temperature and high pressure is c(SO2-4)=4.779 6(R+1.469×10-4ΔT+1.340×10-4ΔP),where Ris defined as the ratio of the SO2-4ions band intensity to the OH stretching single band intensity,ΔTis the temperature relative to 23 ℃,ΔPis the pressure relative to 0.1 MPa,23 ℃≤T≤390 ℃,the concentration range of the SO2-4ions is 0.5~1.5mol·L-1,and the uncertainty of the equation is 6.5%.Raman spectroscopy can be used to measure the concentration of the Raman-active species in aqueous solutions.更多还原