Utilization of DTAB as a collector for the reverse flotation separation of quartz from fluorapatite

Reverse flotation desilication is an indispensable step for obtaining high-grade fluorapatite. In this work, dodecyltrimethylammoni- um bromide (DTAB) is recommended as an efficient collector for the reverse flotation separation of quartz from fluorapatite. Its collectivity for quartz and selectivity for fluorapatite were also compared with figures corresponding to the conventional collector dodecylamine hydrochlor- ide (DAC) via microflotation experiments. The adsorption behaviors of DTAB and DAC on minerals were systematically investigated with surface chemical analyses, such as contact angle determination, zeta potential detection, and adsorption density measurement. The results re- vealed that compared to DAC, DTAB displayed a similar and strong collectivity for quartz, and it showed a better selectivity (or worse col- lectivity) for fluorapatite, resulting in a high-efficiency separation of the two minerals. The surface chemical analysis results showed that the adsorption ability of DTAB on the quartz surface was as strong as that of DAC, whereas the adsorption amount of DTAB on the fluorapatite surface was much lower than that of DAC, which is associated with the flotation performance. During the floatation separation of the actual ore, 8wt% fluorapatite with a higher grade can be obtained using DTAB in contrast to DAC. Therefore, DTAB is a promising collector for the high-efficiency purification and sustainable utilization of valuable fluorapatite recourses.

丁基钠黄药对斑铜矿浮选的吸附动力学和热力学研究（英文）

本文通过吸附动力学和热力学研究不同pH条件下丁基钠黄药(NaBX)在斑铜矿表面的吸附对浮选的影响.浮选试验表明在pH值为9时,斑铜矿在NaBX溶液(4×10^-5 mol/L)中的浮选效果最佳.通过吸附动力学试验表明NaBX在斑铜矿的吸附符合第二动力学方程,属于多分子层的Freundlich模型,最大吸附速率常数为0.30 g/(10^-6mol·min),最大平衡吸附量为2.70×10^-6 mol/g.通过热力学计算的结果表明吸附过程是自发的化学吸附过程,并通过红外光谱分析了表面产物为黄原酸铜、黄原酸铁和双黄药.

Platinum-group element geochemistry of Cenozoic basalts from the North China Craton: Implications for mantle heterogeneity

42 新生代(主要中新世) 从北方中国 Craton 的 Jining， Chifeng， Fansi， Xiyang，和 Zuoquan 区域的暗岩样品(NCC 暗岩此后) 为铂组元素(PGE，包括的 O，红外， Ru， Rh，磅，和 Pd ) 被分析。他们中的大多数是碱的暗岩和 tholeiites，所有几乎不他们显示很少外壳的污染。NCC 暗岩的全部的 PGE 内容从 0.1 ～ 0.9 ppb 变化，原始披风的比那些低的大部分 23.5 珍视 ppb。这些暗岩的原始使披风正常化的 PGE 模式定义积极斜坡和 Pd/Ir 比率从 1.2 ～ 25 变化。以 PGE 内容和 Pd/Ir 比率，他们相当类似于海中央山脉暗岩。在 PGE 之间没有明显的否定关联，显示在 magmatic 期间的橄榄石，辉石，或硫化物的部分结晶化处理对在 NCC 暗岩的 MgO， Ni，和 Cu 不能是为观察 PGE 变化的控制因素。NCC 暗岩的观察 Pd/Ir 变化要求异构的披风采购的 non-chondritic 的参与。基于 Sr-Nd-Pb-Hf 同位素的 systematics 和不兼容元素的签名，一混合部分在岩流圈的顶从 asthenospheric 橄榄岩和围住的披风 eclogites 融化为这些 NCC 暗岩的起源被建议。eclogites 的透镜从再循环的大陆人外壳的 upwelling 被导出在期间向西从 600 km 断绝地区的和平的板的 subduction。这些暗岩的 PGE 地球化学提供独立证据支持这个结论和观察 Pd/Ir 变化可以在拍的 peridotitic 的比例反映变化， eclogitic 融化。