Amberlite ira 67

Hydrochloric acid (Guaranteed Reagent) was redistilled in a sealed vessel to remove the exogenous B. The cesium carbonate (spectroscopic pure) was of 99.994% purity. High-purity graphite was added to a mixture of ethanol solution (80%) to obtain the final solution corresponding to 13 mg/g graphite. The isotopic reference standard used in this study was NIST SRM 951 boric acid (Gaithersburg, MD, USA). A solution of mannitol of 1.82% (w/v) and Cs₂CO₃ solution containing 12.3 mg/mL of Cs⁺ was also prepared. Sodium carbonate, ammonia hydroxide, and sodium chloride were of the analytical grade reagent. Borax and boric acid were of Guaranteed grade Reagent.
The resins, B specific resin Amberlite IRA 743, strong cation exchange resin Dowex 50W X8, and weakly anion exchange resin Amberlite IRA 67, were purchased from Sigma-Aldrich Co. LLC, China.
High purity water with a B blank less than 0.008 μg was redistilled by subboiling distillation and passed through a resin column filled with B specific resin (Amberlite IRA 743), which was used to prepare the standard solution and working solution.
An inductively coupled plasma optical emission spectrometer (ICP-OES, Vista MPX, Varian, USA) with a 40 MHz radio frequency generator and a charge coupled device detector (Vista Chip) was used to detect B.

The adsorbents were produced by Sigma-Aldrich (Saint Louis, MO, USA) and consisted of a strong-base anion exchanger (Amberlite IRA958, chloride form), weak-base anion exchanger (Amberlite IRA-67, free base), and hydrophobic polyaromatic resin (Amberlite XAD4, 20–60 mesh). The resins were first soaked in deionized water (6 parts water to 1 part resin) for 3 h. The wash was repeated until the conductivity of the solution was less than 1 µS/cm, which required three washes for each resin. The washed resins were then dried in an oven at 50 °C for 48 h before the experiments.