Boron recovery from clay waste using Diaion CRB‐02 resin

Abstract

A two-step process for boron recovery from clay waste is proposed in the present work. The leachate obtained after the clay waste was leached with sulphuric acid solution was treated with Diaion CRB-02 - a boron-specific resin for the separation of boron from the alkaline species in the leachate. The batch studies showed that a maximum boron recovery of about 95% was obtained at a pH value of 8.0, an initial boron concentration of 50 mg L(-1), a contact time of 24 h and a temperature of 25 degrees C. Equilibrium sorption data fitted the Langmuir isotherm. Column studies were carried out using different inlet boron concentrations and flow rates at a pH value of 8.0 and a temperature of 25 degrees C. The Yoon-Nelson and Thomas models were used to describe the dynamic behaviour of the column and to determine the column kinetic parameters. By these models and graphical integration, the column capacity values were found to be 7.3-8.5 mg g(-1) and 7.1-8.5 mg g(-1), respectively, and the 50% breakthrough time values were found to be 21-155 min and 19-149 min, respectively, depending on the inlet concentration and flow rate. It was observed that about 76% of the boron in the leachate solution could be recovered at an inlet boron concentration of 250 mg L(-1), a flow rate of 2.5 mL min(-1), a pH value of 8.0 and a temperature of 25 degrees C.

Modelling of Boron Removal from Solutions Using Purolite S 108 in a Batch Reactor

“…This increase was due to the exothermic nature of adsorption . While a similar temperature effect was obtained for Diaion CR 02 resin , the reverse of the trend obtained in the present study was reported for Amberlite IR‐743 resin . The boron adsorption capacities of Purolite S 108 resin for 1, 15, 30, 45, and 60°C were found as 9.013, 8.272, 7.765, 7.338, and 7.260 mg/g, respectively.…”

“…This result was attributed to an increasing molar fraction of monoborate and polyborate anions with initial pH increase to pH 8.5 . A similar pH effect on boron removal was reported for other N ‐glucamine‐type chelating resins such as Amberlite IR‐743 and Diaion CRB 02 . The pH change of solutions with time is given in Fig.…”

“…However, the resin was in the hydroxyl form for the second, third, and fourth usages, and therefore the resin particles neutralized the acidic solution and solution pH levels increased. Owing to resin deterioration, the resin capacity decreased after the third regeneration .…”

Boron removal by coagulation using Al(OH)3 and factorial optimization of data for boron mine wastewater

“…Therefore, the aluminium hydroxide flocs showed highest removal efficiency against boric acid molecule and monoborate anion at pH 8 as related with the equilibrium by OH ions. Because OHanions compete with the boron ions at high pHs above 9 and removal efficiency decreased above pH 9 [17].…”

A new adsorbent for boron removal from aqueous solutions

“…For boron removal, the main processes that have been studied are: (1) coagulation and coprecipitation [6][7][8], (2) ion-exchange using boron-selective ion-exchange resins [9][10][11], (3) solvent extraction [12,13], (4) membrane technologies [14][15][16] and (5) adsorption on activated carbon [17][18][19][20]. Among them, the use of boronselective resins is the most efficient method, but in contrast it is not economical because of high regeneration costs and expensive resins [21,22].…”