Best way to raise pH without alkali metal? [closed]








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I have a process that requires pH~14-14.5 to work. I’ve been achieving this with concentrated NaOH solutions, but the Na cations are later causing side reactions which are detrimental. Is there any organic base/non-alkali base that has the solubility in water and pKa to reach these pH values? 




**Tetramethylammonium hydroxide**


This is a strong base like NaOH. 


See [Behavior of Polyethylene Oxide Based Nonionic Surfactants
in Silicon Processing Using Alkaline Solutions](http://jes.ecsdl.org/content/142/2/621.full.pdf+html) *J. Electrochem. Soc.* 1995 volume 142, 621-627: 



> 
> alkaline cleaning solutions based on quarternary ammonium hydroxides such as choline ($pK\_b = 0.1$) and tetramethyl ammonium hydroxide ($pK\_b = 0$) 
> 
> 
> 


and [Ceramic Nanomaterials and Nanotechnology II](https://books.google.com/books?id=Gb9RAAAAMAAJ&q=%22tetramethylammonium%20hydroxide%22%20complete%20dissociation&dq=%22tetramethylammonium%20hydroxide%22%20complete%20dissociation&hl=en&sa=X&ved=0ahUKEwjb9rnMnPLZAhVNyGMKHUjvCO8Q6AEISDAI) which says: 



> 
> In this research, tetramethylammonium hydroxide (TMAH) was used, instead of KOH, to adjust pH of the precursor solution to 14.0 
> 
> 
> 


Also, [TETRAMETHYLAMMONIUM HYDROXIDE](http://pubs.rsc.org/-/content/articlepdf/1905/ct/ct9058700955) *Journal of the Chemical Society* (1905): 



> 
> An estimation of the strength of the base by means of the velocity
>  of saponification of methyl acetate in N/80 solution showed that it was
>  somewhat weaker than sodium hydroxide. The velocity constants obtained at 25 [degrees] were 0.0106 and 0.0115 respectively, so that if the
>  strength of sodium hydroxide is represented as 100, that of tetramethylammonium
>  hydroxide, under the above conditions, will be represented by 92.
> 
> 
> 


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Water solutions of [amines can get to pH+ 12](https://www2.chemistry.msu.edu/faculty/reusch/virttxtjml/amine1.htm) or so. [Piperidine, $\ce{(CH2)5NH}$](https://en.wikipedia.org/wiki/Piperidine), is about pH 11.


To get much higher pH+ requires somewhat exotic fluorinated organic chemicals, such as [$\ce{9-COO-Me-fluorene}$, $\ce{(4-Me-C6F4)2CHCN}$ or $\ce{(4-Me-C6F4)(C6F5)CHCN}$.](https://www.chemistryworld.com/Pictures/web/c/r/a/Bronsted-table_smaller.jpg) See [Paenurk *et al*, *A unified view to Brønsted acidity scales: do we need solvated protons?*](http://pubs.rsc.org/en/Content/ArticleLanding/2017/SC/c7sc01424d#!divAbstract) and download the PDF for an interesting explanation.


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