Synthesis and Scale Inhibition Performance of a New Amino Dimethylene Phosphonate

Three kind of organic phosphonates were synthesized, including dodecyl-amino dimethylene phosphonate (DAMP), octadecyl-amino dimethylene phosphonate (OAMP), and dioctyl-amino dimethylene phosphonate (DOAMP). The influential factors on organophosphorus recovery of DAMP were investigated and the ideal reaction conditions were determined: the molar ratio of formaldehyde to laurylamine was 2.5 and phosphorous acid to laurylamine was 3.5, at a reaction temperature of 105℃ and a reaction time of 3.5h, the added amount of water was 15mL and chlorhydric acid was 5mL. The structure of synthetic products were characterised and analyzed through IR spectroscopy and NMR spectroscopy. In additional, the scale inhibition performance of these synthetic products were measured, and the anti-scaling rate to calcium sulfate with DAMP and OAMP concentration of 10mg/L are 97.373% and 92.078% respectively.