Making Nitric Acid Without Distillation?

After making sulfuric acid by diaphragm electrolysis more than a year ago, I've had a few requests to try making nitric acid by the same process, and have decided to give it a go in this video.

By electrolysing a solution of potassium nitrate, we slowly generate nitric acid on the anode, as a result of the electrostatic attraction between the anode and the nitrate ion, and the formation of hydrogen ions on the anode surface. Using a semi-permeable diaphragm between the two electrodes, we can isolate the nitric acid we generate, and collect it after running the cell for a day or two.

Sadly, testing the current setup for this length of time only yields about 250mL pf nitric acid at a very low concentration (0.7M at best), which is not particularly useful when compared with the concentrated stuff, in fact, to dissolve copper metal I first had to concentrate the acid by a factor of 3.

In order to be a viable production method, some changes must be made to the process. Possibly, changing the volumes of the chambers, lengthening the run time, or adding a second diaphragm to prevent the reduction of nitrate ions on the cathode may improve the yield, but maybe I'll try that in another video.

Видео Making Nitric Acid Without Distillation? канала Scrap Science