Dehydration technology of bischofite by butanol complexation distillation

The dehydration technology of bischofite by butanol complexation distillation was studied by such methods as X-ray diffraction and elementary analysis. The results show that the dehydration efficiency improves with the increase of the amount of butanol during the continuous distillation dehydration process; the first four coordinated water molecules in bischofite can be more easily taken away than the last two coordinated water molecules, especially the last one; the ultrasonic pretreatment of the bischofite butanol solution is beneficial to deep dehydration of bischofite and high utilization efficiency of butanol; the dewatering rate of bischofite increases when prolonging the ultrasonic pretreatment time; the dewatering rate reaches 90.25% when ultrasonic pretreatment time is 15 min and the total amount of butanol reaches 10 times of original butanol. However, dewatering rate is only 84.86% when there is no ultrasonic pretreatment. The single butanol complexation dehydration technology cannot take all coordinated water molecules in bischofite away.