Algae Star Polymers With Poly(Gamma-Amino Acid) As Arms For Phosphate Scale Inhibition

Calcium phosphate scaling is a big concern in water-processing industry. Many phosphate based scale inhibitors have been reported to mitigate the mineral scaling problems, but their efficiency is low. Furthermore, they are not economic and environmentally friendly. Present work aims to synthesize novel star-shaped antiscalant with dendrite structure having.amino acid arms attached to the algae surface. Their potential in phosphate scale inhibition has also been potentiated by immobilizing calcium on the synthesized star polymers; as Ca2+ ions have strong affinity/compatibility for PO(4)(3-)ions. The as-synthesized anti-scalants were characterized by the Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), Elemental analysis (EA) and scanning electron microscope-Energy dispersive X-ray spectroscopy (SEM-EDX). The scale inhibition experiments were performed by titrimetric and colorimetric studies as a function of time, temperature and pH. The morphological and elemental compositional changes in the scale structure after the treatment with the as-synthesized anti-scalants was also studied as a function of pH or temperature by X-ray diffraction (XRD) and SEM-EDX. Results obtained show that the addition of the synthesized anti-scalants decreases the size of the Ca-PO4 complex crystallites, which are non-adherent and irregular in shapes (flower and cascade). Additionally, the dendrimer inhibited Ca-PO4 deposit formation for more than 25 days of complexing with Ca2+ ions by lowering the super-saturation concentration. Dendrimers reduced maximum 68% Ca2+ ions and 76% PO43- ions in the solution.