Determination of Manganese Concentrations with Different Valences in Water Based on Digital Imaging Colorimetry
The industrial wastewater of electrolytic manganese containes high concentration of manganese.The method for rapid determination and calculation of different valence of manganese concentrations in water based on digital imaging colorimetry was established.In acidic conditions,trivalent manganese[Mn(Ⅲ)]and tetravalent manganese[Mn(Ⅳ)]reacted with ABTS to produce green ABTS radicals(ABTS·+),and the stoichiometric relationships were 1∶1 and 1∶2,respectively.In acidic and excessive sodium pyrophosphate complexing agent(PP)conditions,the introduction of excessive ozone would make divalent manganese[Mn(Ⅱ)]into seven valence manganese[Mn(Ⅶ)].The stoichiometric relationship between Mn(Ⅶ)and ABTS was 1∶5.The color solution was photographed by mobile phone,and the picture was imported into the software compiled by Python language to obtain the RGB value.At the same time,its efficient computing ability was used to measure and calculate manganese with different valence states.In the optimized experimental conditions,the absorbance was linearly related to the corresponding red channel(R value)in the RGB signal.The linear equation was y=-0.018x+2.46 with R2=0.991,and the detection limit was 0.03.This method has the characteristics of high detection efficiency,low cost and high accuracy,and it can be used for on-line monitoring of manganese during the discharge of electrolytic manganese wastewater.
manganese with different valenceABTS methoddigital imaging colorimetryPythonozonation
万方数据
维普
