抑制剂对红柱石与粉石英浮选分离效果研究

文章以油酸钠作为捕收剂,研究了磷酸氢二钠、柠檬酸和硅酸钠等抑制剂对红柱石和粉石英浮选分离效果的影响。结果表明:以油酸钠为捕收剂时,最佳的浮选条件为油酸钠浓度为3.3伊10-3mol/L,pH=8.5,磷酸氢二钠浓度为4.7伊10-3mol/L,两种矿物的浮选回收率差可达到最大值,为47.86%。红外光谱分析表明,油酸钠对红柱石有物理、化学两种吸附,对粉石英仅有物理吸附,因而对红柱石捕收能力更强,抑制剂磷酸氢二钠对粉石英表面起解吸作用,能有效地分离抑制粉石英起浮,从而实现两者的分离。     

组合捕收剂浮选菱锌矿的分子头基尺寸响应

通过单矿物浮选、动电位测试以及荧光探针检测对比研究了不同头基尺寸捕收剂组合油酸钠/十二胺和油酸钠/溴代十六烷基吡啶在菱锌矿表面的吸附特性及其对矿物浮选行为的影响。单一捕收剂体系浮选试验结果表明,3种捕收剂体系下,随着捕收剂浓度增加,矿物浮选回收率均呈现先增加后下降的趋势,油酸钠、溴代十六烷基吡啶、十二胺分别在pH值为5.8、8.4和10.1处达到最大回收率,3种捕收剂对菱锌矿的捕收能力顺序为油酸钠>溴代十六烷基吡啶>十二胺。混合捕收剂体系中,固定油酸钠浓度为2×10^-4 mol/L,加入适量的十二胺可以大幅促进矿物浮选,而加入溴代十六烷基吡啶几乎没有影响。动电位测试结果表明,在pH=6时经2×10^-4 mol/L 油酸钠溶液处理的菱锌矿表面电位为-30.5 mV,随着十二胺用量增加,已吸附油酸钠的菱锌矿表面电位逐渐上升,在十二胺浓度2×10^-4 mol/L时其表面动电位升高到接近菱锌矿在纯水中的动电位值22.3 mV,这是由于十二胺阳离子在已吸附了油酸钠阴离子的菱锌矿表面发生吸附; 而溴代十六烷基吡啶的加入对菱锌矿表面电位几乎没有影响,说明溴代十六烷基吡啶阳离子基本没有在矿物表面吸附,这与浮选试验结果一致。矿物表面微极性测试结果验证了上述推论,在此基础上给出了两种组合捕收剂在菱锌矿表面的吸附模型。     

磨矿介质对长石和石英浮选行为的影响及机理分析

研究了长石和石英在湿式磨矿条件下,分别选用十二胺和油酸钠作为捕收剂,锆球和铁球作为磨矿介质时的浮选行为;并通过检测矿浆中典型金属离子浓度和矿物动电位,借助于矿物表面X-射线光电子能谱(XPS)检测,剖析磨矿介质对矿物浮选影响的机理。研究表明,采用十二胺作为捕收剂时,无论是铁球湿磨还是锆球湿磨,长石的回收率都高于石英;采用油酸钠作为捕收剂时,锆球湿磨长石和石英均不浮,铁球湿磨长石和石英的可浮性存在一定差异。矿浆中典型金属离子浓度、矿物动电位和矿物表面XPS的检测结果表明,锆球湿磨长石和石英矿浆中金属离子浓度高,不利于阴离子捕收剂浮选;铁球湿磨时,长石和石英零电点对应的p H值比锆球湿磨高,在两种矿物表面均检测出铁的羟基络合物,这不利于阳离子捕收剂浮选,而有利于阴离子捕收剂浮选。     

微细粒石英对萤石浮选特性的影响研究

通过萤石和石英的纯矿物浮选试验、二者质量比为1∶1的人工混合矿浮选试验、表面电位分析和药剂吸附量测定,系统地研究了油酸钠浮选体系中微细粒石英对萤石浮选效果的影响。结果表明,在pH=6时,石英颗粒表面荷负电,萤石颗粒表面荷正电,二者易发生异相凝聚,降低油酸钠在萤石颗粒表面的吸附,造成浮选指标下降;氟硅酸钠能够有效抑制石英;六偏磷酸钠通过调节矿物表面电位,可改善萤石-石英体系分散程度,提高浮选指标。萤石与石英的人工混合矿矿浆在六偏磷酸钠、氟硅酸钠和油酸钠浓度分别为3×10~(-5)、2×10~(-5)和6×10~(-5)mol/L时,浮选精矿萤石品位达97.10%、回收率为60.80%。     

油酸钠在红柱石与粉石英表面的吸附机理

本文通过Zeta电位测定、红外光谱分析等手段,研究了油酸钠在红柱石、粉石英表面的吸附机理及pH值对吸附的影响。结果表明,离子-分子缔合物是浮选过程中的重要活性组分。Zeta电位以及红外光谱分析表明,油酸钠对红柱石和粉石英均有吸附作用,其对红柱石吸附作用较强,存在化学吸附,对粉石英的吸附较弱,从而可以实现二者的浮选分离,浮选条件为油酸钠的浓度为3×10~(-3) mol/L,pH值=9。     

阳离子-阴离子组合捕收剂浮选分离白钨矿和方解石

通过纯矿物浮选试验、红外光谱分析、表面张力测定以及动电位测试研究了阳离子捕收剂十二胺(DDA)和阴离子捕收剂油酸钠(NaOL)及其组合捕收剂在白钨矿和方解石浮选分离中的作用及机理。结果表明,当pH值为7左右,DDA和NaOL组合捕收剂总用量为1.5×10^-4 mol/L、组合比为9∶1时,白钨矿回收率达到95%,比单独使用DDA、NaOL以及DDA和NaOL组合比为1∶9时明显提高;在该比例下预先加入2.0×10^-3 mol/L的酸化水玻璃,白钨矿回收率仍然达到90%,而方解石回收率由80%下降到了40%,这可以实现白钨矿和方解石的浮选分离。     

十二胺和十二烷基磺酸钠在长石石英表面的吸附

采用浮选试验、ζ-电位和FTIR光谱分析,研究了十二胺(阳离子捕收剂,DDA)和十二烷基磺酸钠(阴离子捕收剂,SDS)作捕收剂在长石石英表面的吸附。浮选结果表明,pH值在2附近时,长石和石英的浮游差最大,混合捕收剂能增大二者的浮游差,有利于长石的优先浮选。在单一捕收剂中长石和石英ζ-电位均整体向正或负方向移动,在混合捕收剂溶液中,二者ζ-电位在碱性介质中正移幅度较酸性介质明显。FTIR光谱结果表明,pH值为2时,DDA在长石和石英表面均只存在物理吸附;SDS在长石表面既存在物理吸附,还与Al-O形成化学吸附,而在石英表面仅存在物理吸附;混合捕收剂在长石表面既有物理吸附,还存在氢键作用,而在石英表面仅存在物理吸附。     

阴离子捕收剂浮选一水硬铝石溶液化学机理

利用激光动电位测定一水硬铝石的等电点为pH =6 2。用阴离子捕收剂十二烷基磺酸钠和油酸钠浮选一水硬铝石 ,十二烷基磺酸钠与一水硬铝石以静电作用为主 ,并发生半胶束吸附 ,最佳浮选范围为pH <6 2 ;而油酸钠浮选一水硬铝石时为化学吸附 ,当油酸钠浓度为 1× 10 - 4 mol L时 ,一水硬铝石最佳浮选范围为pH =5～ 9。溶液化学计算得到的油酸钠浮选一水硬铝石的pH值上限和下限与试验结果一致。红外光谱分析证明油酸钠在一水硬铝石表面发生了化学吸附     

浮选法对非晶微硅粉提纯效果的研究

为确定效果最优的纳米石英浮选工艺条件,采用浮选法对微硅粉分离提纯,考察了捕收剂用量、不同金属阳离子活化剂种类、矿浆pH值、搅拌强度、引入纳米气泡等条件对纳米石英提纯效果的影响。结果表明:在浮选机转速为2000 r/min、矿浆pH值为12、捕收剂(油酸钠)用量为1.5 g/L、活化剂(CaCl₂)用量为5×10^-3mol/L条件下,纳米石英的回收率可达到70.2%,品位可达93.45%。将纳米气泡发生器与浮选机联合使用组成矿浆循环系统,使矿浆中充满纳米气泡,在相同试验条件下,纳米石英回收率比使用去离子水时提高了9.7个百分点,表明引入纳米气泡提高了气泡和微细矿物颗粒间的碰撞和附着概率,对浮选效果有一定的改善。     

用十二胺和油酸浮选菱锌矿的吸附研究

用Zeta电位、接触角、微量浮选和漫反射FT-IR光谱测量了在不同pH值下不同浓度的硫化钠、十二胺(DDA)和油酸(OA)与菱锌矿的作用.浮选结果表明,在十二胺浓度1.6·10-3mol/L和pH 11.5时,浮选回收率和接触角分别提高到94%和115°,研究发现,最佳硫化钠用量为2.6·10-2mol/L.Zeta电位测量显示,纯菱锌矿晶体表面经DDA处理后只有较少的负电荷.在油酸浓度1.1·10-3 mol/L和pH 10时,油酸浮选的回收率和接触角分别提高到93%和105°.油酸处理菱锌矿表面后,矿物的Zeta电位显示比较负的电荷.用DDA调整后,菱锌矿的FT-IR光谱证实DDA在菱锌矿表面上的吸附,光谱测量表明,硫化钠处理后,该矿物表面部分变为ZnS层.该光谱还证实油酸处理后在菱锌矿表面上形成了锌的油酸盐(油酸锌).用阳离子和阴离子捕收剂的结果比较表明,两种情况下硫化钠不同的吸附密度揭示了在菱锌矿表面上具有不同程度的疏水性.     

New energy vehicle:an opportunity for rare earth magnets

<正>Extracted from Securities Guide 1.Popularity of new energy vehicles—an irresistible market trend1.1 Progress of new energy vehicles Chinese Premier Li Keqiang said recently on a visit to Xi'an BYD Autos that new energy vehicles,especially new energy bus,can lessen environment and noise pollution.He encouraged the use of new     

China rare earth market review

正November 1~10,2014Chinese rare earth market was still inactive.Demand for rare earth products was weak.Consumers took a wait-and-see attitude for lower price.As it was an off season for rare earth products,it was expected that prices of rare earth could continue turbulence at the bottom in short terms.Due to a sharp drop,demand for rare earth from downstream recovered.Affected by new energy vehicles,wind powder and energy-efficient appliances,production of rare earth permanent     

China rare earth market review

正August 1~10,2014 There was some good news in rare earth industry recently.Restructuring plans of rare earth groups led by Baotou IronSteel Group and Xiamen Tungsten Group respectively have been approved by MIIT.And rare earth storage policy,which had been expected for a very long time,has been launched officially.Pushed by the good news,rare earth price started to rebound since August 5.Price of didymium oxide and dysprosium oxide rose about 1% to 2%,averagely.About 10% of     

China rare earth market review

正July 1~10,2014Due to weak demand from downstream industry and slow transactions,rare earth market remained weak and price of rare earth products continued to decline.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,     

注浆加固技术在十三矿-685 m进风大巷中的应用

针对煤矿开采深度不断向深部延伸,掘进巷道受深部高应力的影响越来越大,巷道围岩整体稳定性差,矿山压力显现越剧烈现象,一般锚网喷加锚索支护无法从根本上控制巷道的变形。总结了平煤股份十三矿-685 m进风大巷注浆加固技术,依据对巷道掘进之后变形监测数据的采集,对巷道变形机理进行分析研究,并对注浆时段进行了合理选择,在对巷道的注浆工艺进行了充分论证的基础上,对巷道进行了注浆。注浆后效果表明:巷道滞后注浆时间段的选择非常重要,巷道在恰当的时间内进行注浆加固施工,能有效控制巷道的变形,巷道注浆后变形量明显减小,岩体的稳定性明显增强,减少了巷道日常维修工作,降低了矿井的生产成本,保障了矿井的安全生产。     

Brief news

正China Minmetals Rare Earth Construction of Jianghua Separation Plant is set to complete at the yearend Civil works of Jianghua Separation Plant have been finished and the company is installing and debugging equipments now.It is estimated that construction of Jianghua Separation Plant will be     

Brief news

正Total transactions of rare earth in Rare Earth Ex-change Center of Hunan South Rare and Precious Metal Exchange neared 40 billion yuan from January to October From the opening in January of this year to the end of October,the total transaction of rare earth products in Rare Earth Exchange Center of Hunan South Rare and Precious Metal Exchange neared40 billion yuan.There are 16 varieties including dysprosium oxide and terbium oxide traded on the exchange center,one of the largest trading platforms for rare earth oxides in China.     

Theoretical basis for optimal collector concentrations and pulp pH values during flotation of sulfide-free minerals

A hypothesis that associates optimal conditions of mineral flotation with a zero charge of their surface is put forward. This hypothesis serves as a basis for a methodology to obtain and verify quantitative physical-chemical models for a minimal necessary concentration of a collector during flotation of sulfide-free minerals. These models may be of use for upgrading engineering processes of flotation and as a job for the concentration plant automation systems. __________ Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 89–99, March–April, 2006.     

Annual Report analysis of Chinese rare earth-related listed companies in 2013

<正>Chinese rare earth-related listed companies have published their 2013 annual reports.It can be understood from their reports that production and operation activities of Chinese rare earth-related companies were still heavily affected by macro economy and industrial policies.They basically followed the steps of national economy.In 2013,world economy recovered slowly but the economy     

Market opportunities and challenges for rare earth polishing powder

正1.Status of rare earth polishing powder Rare earth polishing powder with high content of cerium oxide began to replace iron oxide for glass polishing and became one of the key materials in glass polishing process since 1940.Compared with traditional iron oxide,rare earth polishing powder has many advantages,such as fast polishing rate,high polishing quality and long service life.It can achieve good surface quality and improve operation conditions.For example,in lens polishing,the polishing work that cerium