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In modern chemistry, - pH meter, ion electrode, AES, HPLC, etc. replacing titration - HPLC replacing recrystallisation - IR and NMR replacing melting point analysis, derivative analysis, functional group analysis

In other words, are the techniques that being replacing only being used inside school and teaching labs?

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It is true that modern techniques make it faster to elucidate the identity of compounds and isolate them from the reaction mixture, however to call the traditional methods like titration, recrystallization, or column chromatography (basis of HPLC) outdated is far too broad. You could probably get away with calling them outdated if all you wanted to do was to characterize compounds/final product. But when you're in synthesis, you still need the 'traditional' methods to prepare larger amounts of intermediate.

For example, HPLC is only able to separate small amounts of compounds (possibly enough for characterization) and if you wanted enough to go to the next step of your reaction (or if you wanted to make a lot), HPLC would be a highly inefficient way of doing this. Recrystallization, Distillation, and/or Column Chromatography (depending on the compound) would be much better for this purpose.

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As someone working in the analytical industrie, I can tell you that these techniques are far from outdate. This has several reasons:

If you're working in the pharmaceutical analysis, and therefor working with the so called Pharmacopoeias (USP, JP, BP, PhEur) many methods are still based on the classical working techniques. Heavy metals are still often tested as Sulfites, a lot of titration methods are used (Karl-Fischer for water, hydroxyl value...), dry matter, ash testing... This is also due to the limitations of pharmacies, who have to test themselfes and don't own the big and expensive instruments. On another side, this is due to the enormous efforts that neds to be done to update this compendias.

This leads to the next points: costs. A lot of these modern and trustworthy machines are expensive and require a lot of know-how. Not every company can or wants to invest this much money in the analytical equipment, if a technician can do a lot of this cheeper by himself. Please don't think that you can buy a GC/HPLC/NMR..., just put it in place and it works reliable the next 20 years. You have to maintain it, qualify and calibrate it quite often... This also costs a lot of money and time and if you don`t use it 24/7, this will raise the costs per analysis quite a lot.

I will update this further, after work.

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