مرکز منطقه ای اطلاع رساني علوم و فناوري - Filtrations of tincal wastes in SO

Abstract :

Boron ores are used in the production of various boron compounds. One of the most important of them is borax obtained from tincal. One of the most important problems in refined borax production is to separate tincal from the clay minerals which is in colloidal state in aqueous solution and cannot be filtered. For this reason, a lot of coagulants are used and this causes some increase in the cost. On the other hand, there is considerably losing of borax during these processes. For this purpose, CO_2 has been used in previous studies, But sufficiently coagulation has not been provided. Filtration time has been for a long time. In this study, in order to disappear the colloidal state, SO_2 has been used instead of a coagulant. The temperature and stirring time have been chosen as parameters in this work. Since the sample was having to broken into small pieces structure, particle size was not investigated as a parameter. Thus, it has been resulted that the colloidal state may disappear and various boron minerals may be dissolved, and in water aqueous media boron loses become minimum. Also, by using this method, it has been examined that without becoming necessary to use a coagulant it can be obtained a more rapid filtration with minimum boron lose. As a result, in a 60-min experiment at 50 ºC, 99. 5% of B_2O_3 contents waste was recovered. In addition, about 84% CaO in the waste was dissolved in the leaching solution.