(1. 北京科技大學(xué) 土木與環(huán)境工程學(xué)院，北京 100083；
2. 中國(guó)科學(xué)院 過(guò)程工程研究所，北京 100190)
摘 要: 對(duì)浮選脫硅后在850 ℃下煅燒3 h的菱鎂礦精礦進(jìn)行浮選試驗(yàn)，分別以油酸鈉和十二胺為捕收劑，水玻璃和六偏磷酸鈉為調(diào)整劑研究了含鈣雜質(zhì)的可選性。通過(guò)ζ電位測(cè)定分析了浮選機(jī)理。結(jié)果表明：以十二胺和水玻璃為捕收劑和活化劑進(jìn)行的反浮選，可以得到MgO品位和回收率分別為76.48%和79.75%，CaO含量為0.24%的MgO與Mg(OH)2混合物精礦。煅燒后的白云石表面因包裹了氫氧化鈣薄膜而吸附了水玻璃水解產(chǎn)物H2SiO3和SiO32−聚合成的膠粒被活化，活化的煅燒白云石再次吸附十二胺，表面變得疏水而上浮。運(yùn)用Material Studio軟件模擬了十二胺對(duì)經(jīng)活化后的煅燒白云石的吸附，比較了六偏磷酸鈉與水玻璃兩種調(diào)整劑的優(yōu)劣。
關(guān)鍵字: 菱鎂礦；煅燒；ζ電位；分子動(dòng)力學(xué)
（1. School of Civil and Environment Engineering, University of Science and Technology Beijing, Beijing 100083, China;
2. Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China）
Abstract:The rough magnesite concentrate, which has been reduced silica with flotation, was separated with a flotation flowsheet again after being calcined at 850 ℃ for 3 h. The separability of dolomite from magnesite was studied, and modifier and collector were sodium silicate, sodium hexametaphosphate and sodium oleate, laurylamine. The flotation mechanism was analyzed through the zeta potential. The results show that MgO and Mg(OH)2 mixed concentrates with MgO grade, recovery and CaO content of 76.48%, 79.75% and 0.24%, respectively, are obtained in the reverse flotation tests using laurylamine and sodium silicate as collector and activator. The dolomite wrapped by calcium hydroxide adsorbed colloidal particle consists of H2SiO3 and SiO32−, H2SiO3 and SiO32− are the product of sodium silicate. Subsequently, the surface of dolomite becomes hydrophobic after adsorbing laurylamine. And using the software Material Studio to simulate the adsorption, when sodium hexametaphosphate and sodium silicate are used as adjustment agent.
Key words: magnesite; calcine; ζ potential; molecular mechanics
