Previously, I wrote about Te Kiri Gold, an extortionately priced product whose desperate users were told could cure cancer and suchlike. The product in question is no more than electrolysed salt water. I sardonically mused that such a product could be made from the reject stream of the reverse osmosis brine electrodialysis process, such as the one used in a chlor-alkali process designed by a team that I was involved with for an undergraduate project. Because of the low production cost and the attractive pricing, our generic Te Kiri Gold would generate a tremendous amount of revenue!
Recently Stuff.co.nz shared an article about another type of magic water, sold here in good ol’ New Zealand under the label of NZ Water Purifier Ltd. This magic water is different; while TKG was a solution of sodium hypochorite, NZ Water Purifier Ltd is a solution of dissolved chlorine dioxide. Chlorine dioxide should not be consumed by humans, let alone anything living. Funnily enough, it can also be produced by the chlor-alkali process!
During my undergrad project, another team also designed a chlor-alkali plant. They targeted it for use in the pulp and paper industry. A Kraft pulping plant is the perfect companion for a chlor-alkali plant since both the chlorine and NaOH are consumed on-site. Sodium hydroxide is used during the cooking and bleaching operations, while the chlorine is reacted with NaOH to produce sodium chlorate (famous for causing trousers to explode), which is reacted with hydrochloric acid to produce chlorine dioxide, which is the bleaching agent used. Judging from the leading photo in the article (higher res at the original article at Newsroom.co.nz), sodium chlorite and HCl are sold in separate bottles* to mix together at home, or you can buy it pre-mixed for convenience.
Economically, how does this compare to TKG? We can’t use electrodialysis dilutate to produce NZ Water Purifier Ltd because the membrane cell requires highly concentrated brine (250 g/L as opposed to 32 g/L). So instead, lets just dump it back into the ocean and re-purpose the plant to make chlorine dioxide.
I’m not exactly sure about the amount of chlorine dixoide that can be produced, but from a crude analysis of the molar ratios in the chemical reaction equations I think there is a 2:1 ratio of sodium chlorate:chlorine. Thus we are limited by the amount of NaOH produced. There is then a 1:1 ratio of Chlorate:chlorine dioxide. Let’s say that from 90,000 t/y of NaOH, we can make 152,000 t/y of chlorine dioxide. (Note that I’ve ignored the production of HCl, which could be achieved from the remaining chlorine that isn’t used to make sodium chlorate. It becomes chlorine again during the reaction to produce chlorine dioxide anyway). Let’s assume we sell the solution at 25 wt%, then we are making 608,000 t/y of solution. Assuming a density of 1 kg/m³, and $190/L, we have a revenue of $116 million/y. Thus, we can conclude that a plant making Te Kiri Gold was a much better investment at $260 million/y in revenue.
Unlike TKG, this is not a kiwi product. In fact, NZ Water Purifier Ltd is already so infamous, that it has it’s own RationalWiki page (under the name, MMS). Consuming chlorine dioxide is a terrible idea, with some very unpleasant health effects. Beyond the usual aspirations of curing cancer, MMS has lately been marketed to parents of autistic children as a way to “detoxify” them. This is no doubt connected to the anti-vaccination movement, which has demonised autistic people as being “damaged” by vaccines. The level of ableist prejudice among the anti-vaccination and alternative medicine communities is outrageous. It only serves to increase the contempt that I have for them.
Fortunately, Medsafe has issued a warning over the product. Even better, the government has introduced the Natural Health and Supplementary Products Bill, which regulates the manufacture, sale, and export of “natural” health products and creates new offences for deceptive behaviour and harming human health. It’s currently at the committee stage prior to the third reading. Let’s get the bill passed and close NZ Water Purifier Ltd down.
*The concentrations of sodium chlorite and HCl are unclear. Are they weight percent, or per weight of water? Either way, it looks like sodium chlorite is in excess when the solutions are mixed. The pre-mix is given as 3000 ppm, is this weight, volume or molar? What a bunch of scientifically illiterate bastards.