Hankel reaction

Hankel reaction disproportionation of potassium benzoate to potassium terephthalic acid... 

In 1977, the German firm Hankel patented the use of synthetic zeolites as a partial replacement for phosphates. The sodium aluminum silicates as zeolites have a particular lattice structure capable of absorbing heavy metal cations through ion exchange process. The role of zeolites that were added to TPS was to soften water by rapid reaction with calcium at normal temperature [4]. 

Hankel, M., Balint-Kurti, G.G., and Gray, S.K. (2000) Quantum mechanical calculation of product state distributions for the 0( D)- -H2 —t OH H reaction on the ground electronic state surface. J. Cham. Phys. 113, 9658-9667. 

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