Black Citric Acid Polymer (PN) Capacity as Raw Material for Cationic Exchanger Realization

The molecular structure of black citric acid polymer (PN) and their hydracids acids functions allowed without doubt their capacities to be potential raw materials for realizing a cationic exchanger. So, the objective of this publication was to study this capacity after activation with sodium hydroxide (NaOH) solution. Two black citric acid polymers PN-2-crispy and PN-3-soft were synthesized whose PN equivalent contents and acidity were evaluated by NaOH-0.05N measuring-out and by Boehm titration. After NaOH-activation which efficacy depends on the PN-size after sieving, two activated-PN were obtained such as PN-2-Na and PN-3-Na whose Na+ contents were determined by HCl-0,049N titration. Then, exchange cationic tests with CaCO3 solution were carried out on these activated-PN and the Ca2+ contents of treated solution and Ca2+ on used PN-2-Na, PN-3-Na was followed by EDTA-complexometric titration. Also, Na+ and Ca2+ on used activated-PN were measuring-out by HCl titration. Results showed clearly that PN once activated with NaOH could carried out cationic exchange and the PN-3-Na was largely active all the time than the PN-2-Na. A global mechanism evolution of these PN-cationic exchange was proposed and also its global kinetic study was done by following-up the [Ca2+] concentration of treated solution. Results showed that these PN-cationic exchange was second order related with [Ca2+] concentration of treated solution and the speed constant of PN-2-Na was inferior to the speed constant of PN-3-Na confirming its Ca2+ retention capacity