A process for removing acetaldehyde efficiently and producing high-purity acetic acid stably is provided. Methanol is allowed to continuously react with carbon monoxide in a carbonylation reactor 1 in the presence of a catalyst system; the reaction mixture is continuously fed to a flasher 2 to form a volatile phase (2A) containing acetic acid and methyl iodide; the volatile phase (2A) is continuously fed to a splitter column 3 to form an overhead (3A) containing methyl iodide and acetaldehyde and a stream (3B) containing acetic acid; the volatile phase (2A) and/or the overhead (3A) is cooled by a first condenser C1, C3 at a predetermined cooling temperature; and the noncondensed gaseous component is further cooled by a second condenser C2, C4 to form a concentrate having a lower temperature and a higher acetaldehyde concentration. Acetaldehyde is efficiently removed by distilling the concentrate having a high acetaldehyde concentration.

A quaternary ammonium salt of formula wherein each of R.sup.1, R.sup.2, R.sup.3 and R.sup.4 is independently selected from an optionally substituted alkyl, alkenyl or aryl group having less than 8 carbon atoms and R.sup.5 is hydrogen or an optionally substituted hydrocarbyl group.

##STR00001##

In certain embodiments, this disclosure relates to methods of treating or preventing nephrogenic diabetes insipidus comprising administering an effective amount of a compound of Formula (I) or derivatives thereof, as described herein, to a subject in need thereof. In certain embodiments, the subject has been diagnosed with nephrogenic diabetes insipidus.

In certain embodiments, this disclosure relates to methods of treating or preventing nephrogenic diabetes insipidus comprising administering an effective amount of 1,1′-(dodecane-1,12-diyl)bis(cyclopropane-1-carboxamide), pharmaceutical salts or derivatives thereof, as described herein, to a subject in need thereof. in certain embodiments, the subject has been diagnosed with nephrogenic diabetes insipidus.

Embodiments are directed to adamantane-intercalated layered double-hydroxide (LDH) particles and the methods of producing adamantane-intercalated LDH particles. The adamantane-intercalated LDH particles have a general formula defined by [M.sub.1-xAl.sub.x(OH).sub.2](A).sub.x.mH.sub.2O, where x is from 0.14 to 0.33, m is from 0.33 to 0.50, M is chosen from Mg, Ca, Co, Ni, Cu, or Zn, and A is adamantane carboxylate. The adamantane-intercalated LDH particles further have an aspect ratio greater than 100. The aspect ratio is defined by the width of an adamantane-intercalated LDH particle divided by the thickness of the adamantane-intercalated LDH particle.

Embodiments are directed to adamantane-intercalated layered double-hydroxide (LDH) particles and the methods of producing adamantane-intercalated LDH particles. The method comprises adding to an aqueous solution a first precursor and a second precursor to form an initial mixture, where the first precursor is Al(OH).sub.3 or Al.sub.2O.sub.3, the second precursor is a hydroxide M(OH).sub.2 or an oxide MO, where M is a metal of oxidation state +2; and the initial mixture has a M/Al molar ratio of from 1 to 5. The method also comprises adding to the initial mixture an amount of adamantane to form a reaction mixture having an Al/adamantane molar ratio of from 0.5 to 2; and heating the reaction mixture to produce adamantane-intercalated LDH particles, where the adamantane-intercalated LDH particles have aspect ratios greater than 100.

In certain embodiments, this disclosure relates to methods of treating or preventing nephrogenic diabetes insipidus comprising administering an effective amount of compounds of the class of alkyl carboxylic acids, such as 1,1-(decane-1,10-diyl)bis(cyclopropane-1-carboxylic acid), pharmaceutical salts or derivatives thereof, and the class of alkyl amides, such as 1,1-(dodecane-1,12-diyl)bis(cyclopropane-1-carboxamide), pharmaceutical salts or derivatives thereof, as described herein, to a subject in need thereof. In certain embodiments, the subject has been diagnosed with nephrogenic diabetes insipidus.