皖南伏岭A型花岗岩的成因——地球化学、锆石U-Pb年龄及Lu—Hf同位素特征

伏岭花岗岩体,位于江南造山带东段的皖浙相邻区,岩浆岩沿着近北东向的宁国—绩溪深大断裂断分布。笔者等对伏岭岩体鱼龙川(γ_(5)^(3-2))单元花岗岩开展了系统的全岩岩石地球化学、LA-ICPMS锆石U-Pb同位素年龄和锆石原位Lu—Hf同位素地球化学研究,结果表明,花岗岩的侵位年龄为131.8±0.9 Ma,富硅、富碱、贫钙、贫铁,具有较高的Rb、Th、U、Ga、Zr和Y含量,较低的Sr、Ba和Nb含量,稀土配分曲线呈现典型的“海鸥式”分布特征,显示强烈的负Eu异常;微量元素原始地幔标准化蛛网图显示明显的Ba、Sr、Nb的负异常。其高SiO_(2)含量和Rb/Sr值、低Ba、Sr含量具备江南造山带东段皖南地区A型花岗岩的典型特征。岩体具有同源岩浆演化特征,源区可能存在磷灰石、钛铁矿的分离结晶作用,而辉石类的分离较少。伏岭岩体主要来源于地壳中镁铁质岩石的部分熔融,其地球化学特征继承于源岩。锆石ε_(Hf)(t)变化范围较小,均在-7.0~-4.6之间,二阶段模式年龄(TDM2)为1478~1630 Ma,伏岭花岗岩可能由中元古代古老下地壳部分熔融形成。伏岭岩体的形成可能受到碰撞作用的影响,岩体形成于后碰撞期,中元古代的基底岩石被大范围的熔融,从而产生了伏岭A型花岗岩。

铜陵新桥层状菱铁矿成因的矿物学证据及成矿意义

安徽铜陵新桥矿区二叠系栖霞组底部和石炭系黄龙组—船山组之间产出层状、似层状菱铁矿矿层。开展菱铁矿矿层成因研究对于深入剖析区域层控矽卡岩型铜铁矿床成矿机制具有重要意义。本文利用粉晶X射线衍射(XRD)、扫描电镜(SEM)对菱铁矿矿石进行矿物学研究,结果发现菱铁矿矿石主要由菱铁矿、石英、伊利石和有机质等组成,菱铁矿颗粒粒径较小,表面具有成岩自生的自形石英硬模的微结构,SEM原位微区成分分析显示菱铁矿中除了主量元素铁,还含有大量的锰、锌和钙。矿石中存在两种微结构和不同成因的石英:表面具菱铁矿硬模和次生加大结构的碎屑石英;具六方双锥、单锥以及生物成因球形的自生石英。菱铁矿矿石的组成和矿物表面微结构表明其为沉积成因,非岩浆热液起源。富有机质和亚铁的沉积菱铁矿层和沉积胶状黄铁矿层协同作用,可能是铜陵地区乃至长江中下游成矿带层状铜铁矿床层控性重要制约因素,以及可能作为燕山期中酸岩浆演化的氧化性含铜成矿流体卸载成矿的地球化学还原障。

铜陵地区晚泥盆世五通组叶腊石的发现及其资源意义

叶山铁矿是铜陵新桥矿田一小型沉积—热液叠加改造型铁矿床。文章采用粉晶X射线衍射(XRD)、扫描电子显微镜(SEM)等研究手段,对叶山铁矿区内晚泥盆世五通组沉积岩进行系统矿物学研究。结果发现,五通组碎屑岩中除了常见的碎屑矿物石英、长石、伊利石和高岭石,还含有大量叶腊石,伴生一定量赤铁矿和针铁矿。XRD定量显示叶腊石含量介于7.54%~70%,且沉积层中部为叶腊石富集层位,其含量皆高于50%。微结构观察发现叶腊石多呈自形—半自形的块状、板条状形态,多环绕石英颗粒生长,甚至有的颗粒已经完全由片状叶腊石组成,但是仍具有石英棱柱状形态的假象结构。化学成分分析显示,岩石样品SiO_(2)含量较高,介于44.47%~80.23%,Al_(2)O_(3)含量介于10.49%~28.75%。根据矿物组成和化学成分特征,铜陵叶山矿区五通组沉积岩已经具有叶腊石矿石品质,矿石类型属于硅铝质叶腊石,这种叶腊石矿石是陶瓷原料、耐火材料、无碱玻璃等重要原料。矿石微结构观察和矿区地质背景综合研究显示,五通组叶腊石可能为区域中生代岩浆热作用下高岭石和石英再活化产物。该研究成果为铜陵乃至长江中下游成矿带内具备类似地质条件、寻找非金属叶腊石粘土矿物资源提供基础矿物学理论支撑。

铜陵包村金(铜)矿床中胶状黄铁矿矿物学及成因解析

黄铁矿是安徽铜陵包村金(铜)矿床中主要硫化物,对热液成因的显晶质黄铁矿已有大量研究,而胶状黄铁矿研究较少且成因存在争议。本文以粉晶X射线衍射、扫描电镜(SEM)、透射电镜(TEM)以及拉曼光谱(RS)为主要研究方法和手段,对包村金(铜)矿床中胶状黄铁矿的矿物组成和微结构进行研究。包村胶状黄铁矿主要由黄铁矿组成,含有白铁矿、菱铁矿、石英、含铁白云石、高岭石和有机质。黄铁矿主要以纳米-亚微米粒径的自形、半自形的立方体为主,少量微米级他形颗粒,显著不同于胶体或非晶态的无定型黄铁矿。由黄铁矿、白铁矿和有机质组成的胶状结构中,白铁矿和有机质富集在暗色环带,黄铁矿相对富集在浅色环带,浅色和暗色交替变化主要由三者含量变化所致,与矿物粒径无关。结合铜陵地区胶状黄铁矿研究成果,我们认为铜陵地区乃至长江中下游成矿带内铜-金-铁多金属硫化物矿床相关研究文献中记载的胶状黄铁矿为铁硫化物、碳酸盐矿物、黏土矿物、石英和有机质组成的矿物集合体,是在陆源物质输入受限的半封闭海盆环境下经生物化学作用直接沉淀的纳米-亚微米黄铁矿为主的矿物集合体。虽然胶状黄铁矿经历沉积成岩作用和中生代岩浆热液叠加改造作用,但是沉积微结构、矿物成因信息仍然被有效保存。

安徽巢湖三叠系东马鞍山组鸟眼构造成因研究

鸟眼构造是碳酸盐岩地层中一种特殊的构造,指示潮上潮间带沉积环境。安徽巢湖地区三叠系东马鞍山组底部普遍发育一层鸟眼构造,但对其矿物学、地球化学特征及成因还缺乏基本的认识。通过光学显微镜、粉晶X-射线衍射(XRD)、拉曼光谱分析及LA-ICP-MS原位微区元素含量测定等方法,对东马鞍山组鸟眼构造的矿物学及元素地球化学特征进行探究。结果表明:鸟眼内部矿物组合以方解石为主,石英及黏土矿物含量较低,方解石晶粒较大且由核部到边部晶粒逐渐变小,富集Sr、REE等离子半径较大的元素;基质矿物组合以白云石为主,石英及黏土矿物含量多于鸟眼核部,有机质含量较高,主要富集Fe、Cu、Ti等离子半径较小或不易迁移的元素。这些综合信息反映了巢湖东鞍山组鸟眼构造是由成岩阶段基质白云岩化析出Ca,在沉积有机质分解聚集形成的气泡孔洞中重新沉淀形成方解石而成。

甘肃临泽正北山凹凸棒石黏土矿物学及形成机制

甘肃省临泽县凹凸棒石黏土矿储量丰富,是重要的天然纳米矿物资源。本文采用X-射线衍射(XRD)、扫描电镜(SEM)以及透射电镜(TEM)等纳米矿物学的研究手段,对甘肃省临泽县正北山矿区凹凸棒石黏土矿床的矿物组成和微观形貌、结构特征进行了分析。结果表明,不同矿层的矿物成分相似,主要有石英、长石、白云石、方解石、石盐、石膏以及黏土矿物,其中黏土矿物以凹凸棒石和伊利石为主,含有少量的高岭石、绿泥石、蒙脱石以及伊蒙混层矿物。各矿层矿物含量差别较大,其中碎屑矿物石英含量介于12.35%~64.34%之间,凹凸棒石含量为10.31%~37.93%。根据主要矿物组合及含量将矿石划分为5种类型:凹凸棒石黏土、伊利石型凹凸棒石黏土、碳酸盐型凹凸棒石黏土、富石膏型凹凸棒石黏土以及石膏矿石。SEM和TEM观察发现矿层中普遍存在的凹凸棒石具有长、短纤维两种形态以及由其组成的束状和席状结构,且矿石中发育大量凹凸棒石覆盖或包裹的菱面体白云石和片状伊蒙矿物颗粒边缘外延生长的凹凸棒石微结构,表明凹凸棒石具水溶液沉淀以及前驱体转化等多种形成机制。本研究对甘肃省临泽县地区低品位凹凸棒石黏土资源的综合开发利用具有重要意义。

农药行业NaCl-KCl型废盐热处理研究

采用高温热解—溶解净化—热蒸发结晶—冷却结晶联合方法处理农药行业氯化钠-氯化钾型废盐,获得高纯度氯化钠、氯化钾再生盐,实现将危险废物变成高附加值产品的目的。通过分析废盐中无机、有机成分,考察气氛、温度、保温时间对热处理后废盐中总有机碳(TOC)残余量的影响规律及有机物热解过程,确定氯化钠-氯化钾型废盐热处理最佳工艺参数为无氧气氛、温度在500℃以上、保温时间为10 min;继而采用热蒸发结晶—冷却结晶法分离得到钠盐、钾盐,分离得到的热解碳副产物相对强度比(ID/IG)为0.973、平均孔径为4.00 nm、总孔容为0.0719 mL/g、比表面积为35.96 m^(2)/g;纯化氯化钠、氯化钾再生盐中TOC含量分别为42、189 mg/kg,有机物去除率达到99%以上。纯化钠盐有望用于氯碱工业等领域,纯化钾盐可用于制作钾肥,为废盐资源化利用以及企业解决废盐侵占库存问题提供参考。

碳酸化对白云石热分解产物联合除磷除氟的影响

本文主要研究一种新型吸附剂的制备,及其对磷、氟废水的联合处理。以白云石为原材料,经煅烧和碳酸化处理后,通过XRD、XRF、SEM、FTIR等对其产物组成、形貌等进行表征,同时探究了反应时间、初始磷和氟浓度、固液比、pH值等环境参数对联合除磷除氟的影响。结果表明:随着固液比增大,剩余氟离子浓度逐渐降低后趋于稳定;动力学结果表明氟离子的去除更加符合准二级动力学方程(R 2>0.967);溶液初始pH值对实验结果影响不显著;Langmuir等温吸附模型可以更好地描述氟离子去除过程。煅烧-碳酸化白云石(CCD)联合除磷除氟的机理为:CCD与溶液中的磷发生反应,生成羟基磷灰石,然后OH-被F-取代,转化生成氟磷灰石;同时CCD溶出的Ca 2+、Mg 2+也与F-反应生成相应的沉淀。

氯化钠型废盐中总有机碳的测定方法

氯化钠型废盐所含有的杂质有机物是影响其处理和资源化利用的主要障碍,同时由于氯离子的干扰也使得总有机碳测定、元素分析仪等难以对废盐中的有机物进行定量分析。为了精确定量分析氯化钠型废盐中有机物的含量,避免仪器损坏,作者设计一套专门装置,通过在石英玻璃管反应器中高温完全氧化有机物,使其转变为气态CO_(2),并用碱液吸收柱固定CO_(2),淋洗定容后用TOC分析仪测定溶液中的无机碳含量,从而计算出废盐中有机碳含量。结果表明:方法检出限为0.036%,相对标准偏差和相对误差均在1.5%以内,精密度和准确度较高,为废盐资源化利用研究和生产提供了可供参考的测试方法。

纳米矿物材料净化甲醛污染的研究进展

甲醛(HCHO)是主要的室内空气污染物之一,对眼睛、鼻腔、呼吸道粘膜组织具有很强的刺激性和毒性。目前,吸附法和非均相催化法是应用最广泛的甲醛净化技术。合成吸附剂如活性炭及其各种改性产品存在甲醛吸附选择性差、合成方法复杂且成本较高等问题。贵金属或过渡金属等合成催化剂虽然对甲醛具有降解效率高、不产生毒副产物等优势,但贵金属价格昂贵,过渡金属催化剂也常需热源才能完全降解甲醛,这限制了其广泛应用。随着对纳米矿物材料环境属性的认识不断加深,纳米矿物材料凭借其天然多孔结构、化学稳定性高、表面酸碱性质可调、资源丰富、价格低廉、处理简单等特性,在甲醛净化中具有潜在的优势。然而,不同种类的纳米矿物材料结构与性质也存在差异,因此其对甲醛的吸附或催化反应活性与作用机制也各不相同。天然硅酸盐类纳米矿物材料如海泡石、凹凸棒石、蒙脱石等由于表面具有酸性位点和较高的表面积,对强极性甲醛分子具有一定的吸附能力。然而,未经处理的天然环境中矿物材料存在吸附选择性差、杂质含量多、孔隙少、表面活性官能团数量少等问题,需要对其进行改性处理。目前,天然纳米矿物吸附剂的改性方法主要有酸处理、焙烧活化和引入有机官能团等。酸、热改性可改善纳米矿物如凹凸棒石、硅藻土的表面酸性,增加其孔隙和孔道开放度,从而增大比表面积。在矿物表面引入氨基等有机官能团可将对甲醛的物理吸附转化为化学吸附,并将甲醛矿化为亚胺类物质。合成纳米矿物吸附剂如沸石分子筛具有孔道结构可调、表面积大等特点,也被广泛应用于甲醛的吸附处理,但是甲醛与水汽存在竞争性吸附,且其抗水性能差,这限制了该类材料的进一步应用。相比于吸附法处理甲醛,非均相催化法如光催化、催化氧化可直接将甲醛转化为二氧化碳和水,具有更加广阔的应用前景。羟基磷灰石、水钠锰矿等纳米矿物对甲醛具有一定催化氧化作用,通过掺杂金属元素、调控其结构与形貌可进一步提高其对甲醛的催化氧化能力。纳米黏土矿物如凹凸棒石、海泡石可作为载体与贵金属、过渡金属、纳米二氧化钛等活性组分复合,从而改善活性组分的分散性,提供反应羟基等活性位点,显著提升复合矿物材料的催化性能,在低温乃至室温下就可将甲醛完全降解。本文综述了各种纳米矿物材料在吸附和非均相催化降解室内空气和部分水体中甲醛的研究进展,系统比较了纳米矿物材料对甲醛的吸附、催化性能、反应机理,指出了该材料目前研究存在的问题,并对其今后的发展趋势进行了展望。

添加铁氧化物对水稻土产甲烷微生物EPS性能的影响

近年来的研究报道表明,结晶型铁氧化物对于水稻田土壤中温室气体甲烷产生过程具有促进作用,而胞外聚合物(extracellular polymeric substance,EPS)通常在微生物铁氧化物交互作用过程中扮演重要的角色。文章以针铁矿和赤铁矿为代表,利用化学分析、三维荧光光谱和红外光谱对铁氧化物强化水稻土微生物厌氧产甲烷过程中EPS产生及性能变化进行了分析表征。结果表明:针铁矿和赤铁矿的加入提升了产甲烷速率和底物消耗速率;化学分析表明EPS主要组成为多糖、蛋白质及少量腐殖酸;光谱分析结果表明EPS中存在类色氨酸、腐殖酸和富里酸等物质,其峰强与产甲烷速率和底物消耗速率呈现正相关线性关系;EPS电子接受能力主要来源于腐殖酸和富里酸。研究结果对于认识EPS在水稻田土壤微生物同铁氧化物直接的交互作用以及温室气体排放过程具有一定的参考价值。

Study on Decoloration of Acidic Scarlet GR by Pyrolusite Oxidation under an Acid Condition

Decoloration of acidic scarlet GR by pyrolusite is studied in this paper. The effects of pH in solution, dosage and granularity of pyrolusite, reaction temperature, and vibration speed on decoloration efficiency are discussed. According to experiment results, the decoloration efficiency may exceed 95% for 40 mg/L GR solution by pyrolusite, pH is most important among all factors which impact the decoloration of acidic scarlet GR. Dosage and granularity of pyrolusite, reaction temperature, and vibration speed have a little benitfit on decoloration. The high decoloration efficiency and low removal efficiency of COD as well as FT-IR spectra of products between pyrolusite and acidic scarlet GR indicate that acidic scarlet GR undergoes the redox reaction on the interface of mineral and its chromophore is oxidated and decolored, but it is not removed thoroughly by oxidation.

Structural Evolvement of Heating Treatment of Mg/AI-LDH and Preparation of Mineral Mesoporous Materials

Although hydrotalcite, or layered double hydroxides （LDHs）, is not a common mineral, it is an important material that can be easily synthesized in laboratory. In this study, structural evolvement and BET surface area changes of heat treated Mg/AI-LDH is evaluated by XRD, TEM and N2-BET analyses. The results indicate that the magnesium-aluminum LDH with carbonate as interlayer anion, periclase-like oxides was formed at temperatures of 400-800℃. Meanwhile, 2-3 nanometer mesoporous were formed during decomposition of LDH. However, the heat treated samples still preserve the morphology of the original LDH plates. Periclase-like formed from LDH heat treatment may re-hydrolyze and recover the structure of LDH. However, crystallinity of the recovered LDH is lower than that of the original LDH. This heat treatment will result in formation of （Mg, Al）-oxide nano-crystals and nanopores among the nano-crystals. When heating temperature exceeds 1000, the periclase-like （Mg, Al）-oxide is transformed into a composite with periclase （MgO） and spinel phases. The periclase can be re-hydrolyzed and dissolved in HCl solution. After acid treatment, the sample with a high surface area is composed of spinel nano-crystals and nanopores among them. Our results will provide a new and economic way to synthesize mesoporous materials through pathways of phase transformation of precursor materials with different composition.

铜陵叶山铁矿赤铁矿微尺度矿物学研究及地质意义

铜陵隆起区内广泛分布着铜-铁-金多金属矿床,也存在众多小型铁矿,其中叶山铁矿是典型代表之一。矿体主要产于石炭系黄龙组内,具有层控特征,铁矿化以镜铁矿/赤铁矿为主。为了深入探讨该铁矿的形成机制及与沉积环境的关系,本文对该矿中不同产状的赤铁矿进行了详细野外地质观察和显微结构分析,并将赤铁矿划分为3类(Hem 1、Hem 2、Hem 3)。激光剥蚀电感耦合等离子体质谱(LA-ICP-MS)分析表明Hem 1具有高Si、Al、Ti的特征,微量元素V、Cr、Co、Ni、Cu、Zn、Sr、Ba、Sn、Pb含量相对较高,Co/Ni比值小于1。Hem 1酸不溶物的扫描电镜(SEM)观察显示石英粒径为2～600μm,表面有风成的断面、孔洞、长条状"V"型凹痕等微结构和形貌,同时粘附有纳米硅质小球,表明石英为潮间带环境下的碎屑。以上结果表明该区黄龙组地层存在沉积赤铁矿型铁质建造,发生重结晶作用。Hem 2和Hem 3在主量元素上以低Ti含量,Si、Al、Mn含量变化大为特征;化学组成及元素相关性图解表明Hem 2、Hem 3并非单一成因,可分为两类:高W,低Mn、Si、Co/Ni比值(<1. 5)为沉积-热液叠加改造成因(Hem 2_(SH)、Hem 3_(SH));低W,高Mn、Si、Co/Ni比值(> 1. 5)为热液成因(Hem 2_H、Hem 3_H)。因此,微量元素含量上,Hem 2_(SH)与其共生磁铁矿差异大,Hem 2_H与其共生磁铁矿差异小; Hem 2_(SH)/(Hem 3_(SH))相对Hem 2_H/(Hem 3_H)显示亏损(W元素除外); Hem 2_(SH)、Hem 3_(SH)、Hem 2_H和Hem 3_H各自之间的波动变化,反映了热液改造过程元素的继承性和热液组分演化过程及其对前驱体的叠加影响,但元素相关性图解排除了Hem 1作为Hem 2_(SH)、Hem 3_(SH)前驱体的可能。综上分析结果表明:叶山铁矿可能属于沉积-热液叠加改造型矿床,黄龙组地层存在以菱铁矿为主的沉积铁建造并提供了该矿床的主要成矿物质,受到燕山期岩浆活动驱动的热液流体叠加改造。赤铁矿的多成因特征不仅为认识叶山铁矿的富集过程提供了重要依据,同时也为进一步了解铜陵地区热液改造型铁矿与黄龙组同生沉积环境之间的关系提供了重要启示。

Genesis of Strata-bound Sulfide Orebodies in the Tongling Polymetallic Mineralization Cluster, SE China: Evidence from Colloform Pyrite

Colloform pyrite(CPy)is widely distributed in the Tongling mineralization cluster of the Middle-Lower Yangtze River Mineralization Belt(MLYRMB),China.There have many debates as to whether such CPy is associated with Late Mesozoic igneous or Carboniferous sedimentation.CPy from the Xinqiao deposit,a representative of the stratabound sulfide deposits in the MLYRMB,was studied by powder X-ray diffraction(XRD),field-emission scanning electron microscopy(SEM),and high-resolution transmission electron microscopy(TEM).The results show that CPy mainly comprises pyrite,pyrrhotite,quartz,and illite.Pyrite in CPy shows cubic,globule,and xenomorphic morphologies.No octahedral or pyritohedron was observed.Most of the quartz crystals display xenomorphic morphology,where pyrite mold are popular on the surface.Organic matter(OM),which is usually bound to illite,is an important component in CPy.Morphological investigations which exhibit detrital features of quartz and clay minerals indicate that they were derived from continental weathering.Specially,some hexagonal pyrrhotite nanoparticles which show mackinawite morphology are coexisted with OM.The results indicate that the transformation process of sulfides possibly is mackinawite(the precursor)—hexagonal pyrrhotite-pyrite.Thus,compositional and micro-textural characteristics of CPy in Xinqiao deposit suggest it to be a sedimentary origin rather than a hydrothermal origin which is associated with Yanshanian magmatism.Moreover,the coexistence of CPy and stratabound sulfide orebodies in the MLYRMB suggests a causal link between the two.It is considered that CPy might have served as a Cu mineralization geochemical barrier for the Cu-bearing ore-forming fluids,which originated from the Mesozoic magma in the MLYRMB.

Distribution of Palygorskite in the Lingtai Profile of Chinese Loess Plateau:Its Paleoclimatic Implications

Palygorskite is a typical indicator mineral of the arid and strong evaporation environment. Distribution of palygorskite in loess-red clay sequences may act as an important indicator for reconstruction of the paleoenvironment and paleoclimate. In this paper, field emission scanning electron microscope and high-resolution transmission electron microscope observations on the red clay-loess-paleosol of the Renjiapo profile at Lingtai, Gansu Province indicate that palygorskite occurs widely in red clay sequences formed before 3.6 Ma, but no occurrence has been found in eolian sediments since 3.2 Ma. Micromorphological features and microstructure of palygorskite show that it is an autogenic mineral formed during pedogenesis, and transformed from iilite-montmorilionite under the pore water action. In the Lingtai profile, the disappearance horizon of palygorskite is consistent with those of increasing magnetic susceptibility, dust flux and depositional rate. The distribution of palygorskite in the profile indicates that the interval of around 3.6 Ma was an important transformation period of the East Asian paleomonsoon, when changes took place in the East Asia paleoclimate pattern, i.e. a high-frequency strong fluctuation alternative evolution of the environment. Therefore, palygorskite is a key indicator mineral of the East Asian paleomonsoon evolution of that time.

Magnetic susceptibility of the Xifeng section and its paleoclimate significance

Magnetic susceptibility (MS) is one of the most important indicators of the East- Asia summer monsoon. Presented in this study is a high resolution magnetic susceptibility record from the Xifeng section, which consists of Quaternary loess-paleosol sequence and Pliocene red clay. Variations in magnetic susceptibility are well correlated with the δ18O record in deep-sea sediments and the eolian flux of Greenland. The climatic evolution in the Xifeng section shows that since the Late Tertiary, the driving force of the East-Asia paleo-monsoon is correlated with solar radiation on a 10-ka time scale .

Aluminum Ion Occupancy in the Structure of Synthetic Saponites

Saponite has been widely used in a number of industrial fields because of the higher surface acidity and thermal stability when compared with other clay minerals (Alexander and Dubois, 2000; Casagrande et al., 2005). Due to its limited natural resource, synthesis of saponite has attracted much attention during the last two decades (Vogels et al., 2005; Bisio et al., 2008). The main aim of this study is to investigate occupancy of Al ions and its effect on the structure of synthetic saponites.

Rare Earth Element Geochemistry Characteristics of Laowan Gold Deposit in Henan Province: Trace to Source of Ore-Forming Materials

The compositions of REE in quartz and pyrite from main mineralized stage of the Laowan gold deposit in Henan province and that of quartz from Laowan granite were determined by Inductively Coupled Plasma-Mass-Spectrometry （ICP-MS）. The REE of deposit ore of the Laowan gold deposit, wall-rock and Laowan granite also were studied to trace the source of metallogenic materials in Laowan gold deposit in detail. The range of ∑ REE in quartz and pyrite from gold deposit is 4.18 × 10^-6 - 30.91 × 10^-6, average of 13.39 × 10^-6, 6.68 × 10^-6 of the Laowan granite quartz, obviously lower to REE concentration of deposit, granite and wall-rock. The value of （La/ Yb）N and （La/Sm）N of ore minerals from the gold deposit is 13.23 and 4.17 respectively. The differences in REE parameters, such as δEu, δCe and diffusion degree in REE from light to heavy, among deposit ore minerals and granite mineral are weak. Especially, there are no differences between the chondrite-normalised REE curves of minerals from gold deposit and those of quartzs in Laowan granite, no similarity to wall-rock＇, which shows that ore-forming hydrothermal fluid mainly came from magma fluid resulting from the Laowan granite magma, metamorphic fluid in few. The results also show that REE characteristics of ore minerals in deposit are effective for disclosing oreforming fluid quality comparing with deposit ore＇REE compositions.

Removal of Cu(Ⅱ) From Aqueous Solutions Using Colloidal Pyrite Calcined Under Inert Atmosphere

A natural colloidal pyrite calcined in N2 atmosphere was utilized to remove Cu(II) from aqueous solutions in present work. Effect of calcination temperature, initial solution pH, reaction time, initial Cu(II) concentration, sorption temperature, foreign ions and the dissolved oxygen (DO) on Cu(II) removal was investigated. The results showed that colloidal pyrite calcined at 500-550°C (CCPy) has a most promising potential for Cu(II) removal. The increase of pH, initial Cu(II) concentration and reaction time benefited the improvement of Cu(II) removal efficiency. The isothermal adsorption data of CCPy was well described by Langmuir isotherms and the thermodynamic parameters (ΔG<0, ΔH>0), indicating the endothermic nature of Cu(II) sorption on CCPy. The presence of most common ions in acid mine drainage and DO just had little influence on the Cu(II) uptake. The observation implied that CCPy is a low-cost, abundant material for Cu removal from Cu waters.