ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Synthesis of a copolymer with filter aid, dihydration, and scale inhibition abilities and its application to wet phosphoric acid

Jie Xu and Pan Wang

Chuzhou University, Chuzhou, China

E-mail: jiexu997@yahoo.com

Abstract: A new type of multifunction copolymer PAMA having filter aid, dihydration, and dynamic scale inhibition properties was synthesized using acrylamide (AM) and a homemade polyoxyethylene octylphenol ether acrylic ester (AOP) as the feedstock and persulfate as the initiator in an aqueous solution. The structure of the copolymer was characterized using FTIR and ¹H NMR spectroscopy. Scanning electron microscopy and the software Matlab 7.0 were used to investigate the influence of the copolymer on filter aid and scale inhibition. The results indicated that the copolymer consists of AM and AOP. The filtration rates of the phosphogypsum slurry increased 3.8 times compared to the blank group, and the water content of the phosphogypsum cake was reduced by 10.42% with the addition of 10 ppm of PAMA. The dynamic scale inhibition rate of sodium fluorosilicate and potassium fluorosilicate can reach up to 53.5% when the experiment runs continuously for 12 h. The experiments related to mechanism indicate that PAMA has a strong adsorbability and high bridge effect on the phosphogypsum crystals. Concurrently, PAMA can efficiently improve the microstructure of a filter cake and remove the scale layer of sodium fluorosilicate and potassium fluorosilicate adhering to the wall of a stainless steel pipe, which is beneficial for increasing the filter rate, decreasing the moisture content of the filter cake, and preventing scale layer formation on the filter.

Keywords: Copolymer ; Wet phosphoric acid ; Filter aid ; Dihydration ; Dynamic scale inhibition ability 

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-018-0418-6

Chemical Papers 72 (8) 2035–2043 (2018)