Discussion on the colorimetric method for measuring iron
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Hello everyone! Our unit is measuring: The iron content on the aluminum foil is measured visually and colorimetrically. Every time the iron content is measured, an iron mark must be made. I would like to ask: Can you make a photo of the iron mark with different concentrations like the one used in the textbook when I was studying? In the future, I will not do the iron mark. I will look at the photo every time to see if the concentration is OK, like a PH test paper. Please give me some suggestions. I just think it’s a waste of time and chemicals to make iron marks every time! The company also needs to make a standard solution every time when measuring chlorine on aluminum foil. It is a turbidimetric method to see the turbidity of AgCl precipitation. I also want to take photos of standard solutions with different turbidities. This can save a lot of sample testing time and medicines. Do you think it’s feasible? This post was last edited by lifanwang on 2009-3-26 17:25 ]
It’s really troublesome to do standard samples every day. You try to make a standard sample with different concentrations and compare it with the actual measurement results every day.
1. The specific final decision is in your own hands. According to your ideas, without changing the current analysis method, give it a try and give the photos to different people for judgment to test whether your method is feasible. 2. It depends on your accuracy requirements for analyzing iron and chloride ions. From Cong Tie's perspective, the accuracy is slightly higher. From the perspective of chloride ions, the accuracy is not very high, so you have to treat it differently. 3. Welcome to post frequently.
Just use photometric analysis directly.
It is not good to use photos. Firstly, the color of the photos will be more or less distorted. Secondly, the quality of the reagents used each time may also be different.
Well, yes, using spectrophotometry, simple and straightforward. First make a linear regression equation, and then call up the equation every day. All you need is readings! The maximum absorption wavelength of iron is 510nm.
In fact, there are many analysis methods that analysts have "unintentionally" figured out. You can do it yourself first, but remember to do comparative analysis. Visual inspection is related to the intensity of the light source at the time, so it is unrealistic like pH test paper.
The main reason is that the company will no longer buy spectrophotometers. Also, this analysis does not require high accuracy and is just a reference analysis.
When making micro-volumes, it is better to use constants. If the requirements for constant accuracy are not high, you can consider visual inspection and micro-volume production.
It’s a good idea, but there are the following problems: 1. Allowable error. If your test report requires accurate measurement, you must bring a standard series for each analysis ； If the allowable error is large and the operating methods, reagents, etc. remain unchanged, you can give it a try ； 2. Color cast. Regardless of whether it is a photo or a screen display, there will be a color difference from the actual solution. ； 3. Stability. If the absorbance and slope of the standard curve you measure are almost stable every time, you can try to only bring 2-3 standard points for monitoring each time. :)
The chlorine content is trace and the requirements are not precise. The results are only used as a process reference. How long does it take to detect chlorine in each shift? I wonder if there is a faster way to detect it.
Since it is a daily task, you can consider using a spectrophotometer and choose a suitable spectrophotometer. I use the 723 type spectrophotometer.