JIANG Tao, YIN Lu, ZHU Lei, et al. Preparation of borax from boron concentrate by sodium-roasting and leaching[J]. CIESC Journal, 2014, (2): 737-743.DOI: 10.3969/j.issn.0438-1157.2014.02.052.
a sodium-roasting and water-leaching process were employed for the preparation of borax from boron concentrate
using Na2CO3 as sodium treatment reagent. The effects of Na2CO3 content
roasting temperature and holding time on leaching rate of B2O3 were investigated. Phase compositions and morphologies of roasted products and borax were analyzed by XRD and SEM. The results indicate that the optimal processing parameters are fivefold theoretical amount of Na2CO3
molding pressure of 5 MPa
roasting temperature of 850℃and holding time of 3 h. Under these conditions
activation and alkaline hydrolysis of boron mineral are completed synchronously
which make transformation of MgBO2(OH) into soluble Na3BO3 and Na2B4O7. The leaching rate of B2O3 in roasted products reaches 91.05%. Well-crystallized borax is obtained from leached filtrate after treatments of removing impurity