First, I completely understand that electrolysis to produce chlorates is simple, practical, and inexpensive. I understand that electrolysis to produce chlorates was being used in the late 19th century. I'm wondering, given the (somewhat) limited distribution of electrical power at the time and the ubiquity of chlorates for the production of friction matches, if there was a practical non-electrolysis method of producing chlorates. Wikipedia talks about combining "hot metal hydroxides" (presumably molten) with chlorine gas producing the chlorate. A balanced equation can be written: 6 KOH + 3 Cl2 = 3 H2O + 5 KCl + KClO3But that doesn't mean it reacts that way. Indeed, the melting point of KOH is above the dissociation point of KClO3. :) It appears that you could, theoretically, work your way up from hypochlorite, starting with chlorine gas dissolved in water, with lots of hydrogen chloride produced and discarded: Cl2 + H2O HClO + HCl 3HClO + heat → HClO3 + 2 HCl KOH + HClO3 → KClO3 + H2OBut again, just because you can write the equations doesn't mean the reaction will happen or that it's practical. Anyway, I'm curious about how "all that perchlorate" was made back-in-the-day. If anyone has a pointer to a practical historical method, I'm all ears. My Google searches all seem to turn up the electrolysis route, to the exclusion of everything else.