Determination of sulfite in water samples by flow injection analysis with fluorescence detection

A fast,sensitive,and reliable method for the determination of sulfite（SO3^2-） in fresh water and seawater samples was developed.The proposed method was based on the reaction of o-phthalaldehyde（OPA）-sulfite-NH_3 in alkaline solution,with flow injection analysis and fluorescence detection.The experimental parameters were investigated in pure water and seawater matrixes. The detection limits（S/N = 3） were 0.006μmol/L in pure water and 0.018μmol/L in seawater for SO3^2-.The method was successfully applied to analyze SO3^2- iin the samples of rain water and flue gas desulfurization seawater.

A combination process of mineral carbonation with S02 disposal for simulated flue gas by magnesia-added seawater

The desulfurization by seawater and mineral carbonation have been paid more and more attention.In this study,the feasibility of magnesia and seawater for the integrated disposal of S02 and C02 in the simulated flue gas was investigated.The process was conducted by adding MgO in seawater to reinforce the absorption of S02 and facilitate the mineralization of C02 by calcium ions.The influences of various factors,including digestion time of magnesia,reaction temperature,and salinity were also investigated.The results show that the reaction temperature can effectively improve the carbonation reaction.After combing S02 removal process with mineral carbonation,Ca^2+removal rate has a certain degree of decrease.The best carbonation condition is to use 1.5 times artificial seawater(the concentrations of reagents are 1.5 times of seawater)at 80℃and without digestion of magnesia.The desulfurization rate is close to 100%under any condition investigated,indicating that the seawater has a sufficient desulfurization capacity with adding magnesia.This work has demonstrated that a combination of the absorption of S02 with the absorption and mineralization of C02 is feasible.