FRI-LCR-P-1-CT(R)-03
SYSTEMATIC STUDY ON THE PH RANGES AND BUFFERING CAPACITY OF MIXTURES OF TRISODIUM ORTHOPHOSPHATE OR TETRASODIUM PYROPHOSPHATE WITH POTASSIUM DIHYDROGEN ORTHOPHOSPHATE
Abstract
This study presents valuable systematic data on the pH ranges and potential buffering properties of two phosphate systems composed of alkaline components and anhydrous potassium dihydrogen orthophosphate (KH2PO4) as the acidic counterpart. The alkaline components investigated were trisodium orthophosphate dodecahydrate (Na3PO4.12H2O) and tetrasodium pyrophosphate decahydrate (Na4P2O7.10H2O). The experimental work was carried out in two stages: (i) determination of pH ranges, and (ii) evaluation of buffering capacity. All measurements were performed in quintuplicate using a high-precision pH meter. The full set of results, including raw data, is provided in order to serve as a useful reference for future studies. Detailed descriptions of the procedures and calculations are also included to facilitate reproducibility and to guide further research in this field. Finally, the proposed phosphate mixtures are suggested as reliable pH buffers for technological and biotechnological applications, with particular relevance for metallic surface phosphating.
Keywords
Na3PO4.12H2O, Na4P2O7.10H2O, KH2PO4, pH ranges, Buffering Capacity
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