Stellerite-seeded facile synthesis of zeolite X with excellent aqueous Cd^(2+)and Ni^(2+)adsorption performance

Zeolite X was synthesized by a two-step hydrothermal method using natural stellerite zeolite as the silicon seed,and its adsorption performance for Cd^(2+)and Ni^(2+)ions was experimentally and comprehensively investigated.The effects of p H,zeolite X dosage,contact time,and temperature on adsorption performance for Cd^(2+)and Ni^(2+)ions over were studied.The adsorption process was endothermic and spontaneous,and followed the pseudo-second-order kinetic and the Langmuir isotherm models.The maximum adsorption capacitiesfor Cd^(2+)and Ni^(2+)ions at 298 K were 173.553 and 75.897 mg.g-1,respectively.Ion exchange and precipitation were the principal mechanisms for the removal of Cd^(2+)ions from aqueous solutions by zeolite X,followed by electrostatic adsorption.Ion exchange was the principal mechanisms for the removal of Ni^(2+)ions from aqueous solutions by zeolite X,followed by electrostatic adsorption and precipitation.The zeolite X converted from stellerite zeolite has a low n(Si/Al),abundant hydroxyl groups,and high crystallinity and purity,imparting a good adsorption performance for Cd^(2+)and Ni^(2+)ions.This study suggests that zeolite X converted from stellerite zeolite could be a useful environmentally-friendly and effective tool for the removal of Cd^(2+)and Ni^(2+)ions from aqueous solutions.

Hydrothermal synthesis of zeolites from natural stellerite

Y and P zeolites were synthesized hydrothermally from natural stellerite under different conditions and were characterized via XRD and FT IR. The results show that the higher crystallinity of Y zeolite can be obtained in hydrothermal system with low alkalinity, low Ca 2+ /Na + ratio, and high SiO 2/Al 2O 3 ratio. The lattice space of the samples decreases as crystallization time increases. P Zeolite is prompted under condition of higher alkalinity and higher Ca 2+ /Na + ratio. The intensity and number of bands in the range of 400?cm -1 ～ 900?cm -1 increases with reaction time. Bands at 680?cm -1 , 760?cm -1 and 860?cm -1 corresponding to Y zeolite appear during the crystallization stage. Most of these bands shift to higher wavenumbers when SiO 2/Al 2O 3 ratio increases generally. In the hydrothermal system with reverse condition above, bands at 600?cm -1 , 420?cm -1 ～ 470?cm -1 hardly change as the crystallization time increases and the main crystal phase of P zeolite is obtained.

Geochemical Characteristics,Genesis of Concealed Cu-rich Ore Body in the Jinchuan Deposit,Northwestern China,and Its Prospecting

The Jinchuan deposit is hosted by the olivine-rich ultramafic rock body, which is the thirdlargest magmatic sulfide Ni-Cu deposit in the world currently being exploited. Seeking new relaying resources in the deep and the border of the deposit becomes more and more important. The ore body, ore and geochemistry characteristics of the concealed Cu-rich ore body are researched. Through spatial analysis and comparison with the neighboring II1 main ore body, the mineralization rule of the concealed Cu-rich ore body is summed up. It is also implied that Cu-rich magma may exist between Nirich magma and ore pulp during liquation differentiation in deep-stage chambers, which derives from deep-mantle Hi-MgO basalt magma. It is concluded that the type of ore body has features of both magmatic liquation and late reconstruction action. It has experienced three stages： deep liquation and pulsatory injection of the Cu- and PPGE-rich magma, concentration of tectonic activation, and the later magma hydrothermal superimposition. In addition, the Pb and S isotopes indicate the magma of I6 concealed Cu-rich ore body originates predominantly from mantle; however, it is interfused by minute crust material. Finally, it is inferred that the genesis of the Cu-Ni sulfide deposit is complex and diverse, and the prospect of seeking new deep ore bodies within similar deposits is promising, especially Cu-rich ore bodies.

Study of Cu-rich phase precipitation in austenitic antibacterial stainless steel

Cu precipitation behaviors in two Cu-bearing austenitic antibacterial stainless steels,type 304 and type 317L,were systematically studied by using relatively simple methods for materials analysis,including micro-hardness,electrical resistivity,electrochemical impedance spectroscopy,X-ray diffraction and differential scanning calorimetry.The results indicated that after aging at elevated temperature,the micro-hardness, electrical resistivity,electrochemical impedance and lattice constant of the steel were all varied at different degrees due to the precipitation and growth of Cu-rich phases.The results also showed that the heat evolution during the process of Cu precipitation could be sensitively detected by means of differential scanning calorimetry,obtainning the starting temperature,peak temperature,peak area of the Cu-rich precipitation,and even the activation energy by calculation.The results confirmed that the Cu-rich phased precipitation in the Cu-bearing austenitic antibacterial stainless steel should be a thermal activation process controlled by Cu diffusion.All the materials analysis methods used in this study can be more simple and effective for application in R & D of the Cu-bearing antibacterial stainless steels.

BEHAVIOUR OF Co_5Cr_3Si_2 PHASE IN Cu-RICH ALLOYS CONTAINING Co,Cr AND Si

The major phases in the Cu-rich alloys containing Co,Cr and Si are α-Cu(a solid solution of Co,Cr and Si in Cu),χ-phase(Co_5Cr_3Si_2)and Co_2Si.In comparison with reference sample,it has been detected that the crystal structure of Co_5Cr_3Si_2 is cubic,α-Mn type with a=0.8694 nm.The melting temperature of χ-phase and the alloy are higher than that of the pure Cu,namely,1535 and 1389 K respectively.During ageing treatment,the Co_2Si phase precipitates out from α-Cu and χ-phase simultaneously,but the hardening effect is mainly contributed by the precipitation from α-Cu.

天然沸石对氨氮的吸附作用及其影响因素

通过实验研究天然沸石对氨氮的吸附作用及其影响因素。结果表明,沸石对氨氮的吸附过程遵循准二级动力学模型;沸石对氨氮的等温吸附可用Langmuir和Freundlich等温模型拟合,相关系数R2达到极显著相关(P<0.01);随着天然沸石粒径与投加量的减小,沸石对氨氮的吸附量显著增加;在pH值中性时,去除效果最好;温度升高有利于沸石对氨氮的吸附。

酸处理红辉沸石-碱-铝酸钠-水的水热反应体系中A型沸石的合成

以酸处理红辉沸石为原料 ,采用水热反应晶化合成工艺 ,合成出了质量较高的 4A沸石产品 .在大量实验基础上 ,利用X射线衍射分析、扫描电镜观察等系统地研究了反应混合物的钠硅比 [n(Na2 O) /n(SiO2 ) ]和水钠比 [n(H2 O) /n(Na2 O) ] ,以及晶化时间和晶化温度对酸处理红辉沸石 -碱 -铝酸钠 -水的水热反应体系中A型沸石晶化合成的影响 .确定了最佳工艺技术参数 :硅铝比 [n(SiO2 ) /n(Al2 O3) ]为 2 ,钠硅比 [n(Na2 O) /n(SiO2 ) ]为 1.1,水钠比 [n(H2 O) /n(Na2 O) ]为 45 ,晶化时间大于 6h ,晶化温度为 10

沸石改性及其去除水中氨氮的实验研究

通过实验研究了沸石改性条件及其对水中氨氮吸附去除的影响。结果表明，加热改性与无机酸改性不能显著提高沸石对氨氮的吸附量。利用NaOH改性的最佳浓度为1mol／L，此条件下对氨氮吸附量可提高到650．68mg／kg，为天然沸石的2．82倍。利用无机盐改性时，对氨氮吸附效果最好的是NaCl改性沸石，其次为KCl改性沸石与CaCl2改性沸石。随着NaCl溶液浓度和改性时间的增加，改性沸石对氨氮的吸附量显著增加，可达天然沸石的3～4倍；在NaCl浓度为150g／L与改性时间为18h条件下，改性沸石对氨氮吸附量可达887．35mg／kg，为天然沸石的3．84倍。

红辉沸石合成A型分子筛的红外光谱研究

以天然红辉沸石合成了 A型分子筛 ,通过 XRD、IR光谱研究了其晶化过程。发现在 10 0 0— 95 0 cm-1、75 0— 60 0 cm-1、5 60 cm-1、4 60 cm-1处的红外吸收峰随结晶度有规律的变化 。

红辉沸石合成P型沸石试验研究

以广西资源红辉沸石为原料进行合成P型沸石的最佳工艺流程及相关技术参数研究 ,提出工艺流程为红辉沸石 (酸处理 )→水热反应→晶化→洗涤、过滤→烘干→P型沸石产品 ,最佳工艺技术参数为硅铝摩尔比 [n(SiO2 ) /n(Al2 O3) ]3～ 4 ,碱度 4～ 5mol/LNaOH ,晶化温度 95～ 10 0℃ ,晶化时间 6～ 8h。

红辉沸石合成Y型和P型分子筛的IR研究

首次以天然红辉沸石水热合成了 Y 型、P 型分子筛,以 IR 研究了水热合成体系中分子筛结构的演变及晶相分布规律。研究表明,在高 H_2O/Na_2O、低Ca^(2+)/Na^+体系中,主晶相为 Y 型分子筛,在低 H_2O/Na_2O、高 Ca^(2+)/Na^+体系中,主晶相为 P 型分子筛。

“酸处理红辉沸石-碱-铝酸钠-水”水热反应体系P型沸石的合成

用X射线衍射等测试方法研究“酸处理红辉沸石 碱 铝酸钠 水”水热反应体系混合物的硅铝的量比(n(SiO2 ) /n(Al2 O3) )、钠硅的量比 (n(Na2 O) /n(SiO2 ) )、水钠的量比 (n(H2 O) /n(Na2 O) )以及晶化温度和晶化时间对P型沸石合成的影响 ;确定以酸处理红辉沸石为原料合成P型沸石的工艺流程和技术参数 .工艺流程为 :酸处理红辉沸石→水热反应→晶化合成→过滤、洗涤→烘干→P型沸石产品 ;最佳技术参数为 :n(SiO2 ) /n(Al2 O3) =3～ 4 ;n(Na2 O) /n(SiO2 ) =1 0～ 1.2 ;n(H2 O) /n(Na2 O) =2 8～ 3 7;θ =95～ 10 0℃ ;t=6～ 8h .

红辉沸石吸附性能及其在肥料中应用

以不同粒度改型红辉沸石作为复合化肥的添加剂,探讨了其对肥料中有益组分钾元素的吸附行为。结果显示,改型红辉沸石的添加量为10%、粒度为74μm时,能较好地吸附和实现固定钾,使钾缓慢释放,延长肥料的肥效,同时肥料不结块,可提高成球率,降低成本,有利于贮藏,改善土壤环境。

红辉沸石对重金属铅离子的吸附性能

研究了红辉沸石对重金属铅离子的吸附性能：当pH值在4～5时，红辉沸石具有较好的吸附能力，其对铅的饱和吸附容量达0．831mg／g．同时使用氯化钠和氯化铵对沸石进行改性，并用红外光谱法进行表征，证明处理后的红辉沸石结构上产生了明显的变化，有利于提高其吸附性能，其对铅的饱和吸附容量可达1．091mg／g．

富铜红辉沸石在新疆哈密三岔口铜矿床的发现与矿物学特征

沸石类矿物因其具有特殊的离子交换与吸附性能,因而较早尝试性地应用于一些工业技术领域。随着研究逐步深入,沸石矿物物理化学已经成为当今矿物学科中的一个研究热点。然而同有色金属密切共生的红辉沸石的产出及对其矿床矿物学研究的报道在国内外却为数不多。最近作者在新疆东天山三岔口铜矿考察中发现一种橙红色矿物,经扫描电镜、化学成分、差热-热重、X射线衍射物相鉴定等分析,确认系一种富铜红辉沸石,在新疆地区尚未有见报道。其晶体化学式为(Na2,Ca)Al2Si7O18.7H2O。该矿物同前人资料相比,地质产状虽很相似,但含铜量w(CuO)高达1.02%,超出微含量的范围,Na、Mg含量高而Si低。

广西资源车田红辉沸石特征的初步研究

红辉沸石属斜方晶系，a=1．36，b=1．81，c=1．78nm，V=4.394nm3。化学成分分析结果（％）：SiO258．76，Al2O314.13，CaO8．80，K2O0．11，Na2O0．18，Fe2O30．44，H2O+16．87，H2O1．25。计算的化学式为：（K0.017Na0.042Ca1.13）1.189［Al1.997，Si7.05，O18」·6．75H2O。Si／Al=3．53.N。=1．501，Nβ=1．495，Nγ=1．488。D=2.13g／cm3（实测）。钾离子（K+）交换量9．34～13·08mg／g，氨离子（NH4+）交换量92.76～130．26mmol／100g。佛石晶体呈透明一半透明，为乳白色、瓷白色。单晶体呈板状、板柱状，集合体呈放射状、束状。单晶体长度可达30cm以上，但通常为5～15cm。红辉沸石呈脉状产出在断裂带中，矿体中沸石含量达95％以上，矿石的白度为91．7。它是一种质量较好、用途较广的极为罕见的沸石矿，也是国内外目前唯一具有工业意义的红辉沸石矿床。

红辉沸石的热稳定性研究

红辉沸石是辉沸石族中的一个矿物种 ,属斜方晶系。其化学组成主要为 Si O2 和 Al2 O3,其次为 Ca O。 X射线衍射分析和红外光谱分析研究不同温度下热处理的红辉沸石相变和晶体结构变化特征。研究表明 ,红辉沸石的热稳定性较差 ,其热稳定温度低于 30 0℃ ,结构完全破坏温度为 5 0 0℃。

广西车田红辉沸石的特征及应用研究

在了解红辉沸石矿床地质特征的基础上 ,研究红辉沸石的矿物学特征 ,探索其作为吸附剂在农业上的应用和作为高分子材料增强添加剂的应用。红辉沸石作为化肥添加剂 ,在肥料贮存过程中能吸附有益组份 ,使其在使用后缓慢释放 ,延长了肥料的肥效 ,同时改善了肥料的粒度 ,提高成球率。作为聚丙烯的添加剂能有效地增强其性能、降低成本。

广西资源红辉沸石合成4A沸石的工艺研究

初步研究表明 ,经适当预处理 ,广西资源红辉沸石可作为合成 4 A沸石的优质硅源。通过反复实验 ,探索出了经济有效的原料预处理与 4 A沸石合成工艺流程及相关技术参数 ,既为该地红辉沸石的高层次开发利用开创了新途径 ,又为 4

红辉沸石的耐酸性研究

红辉沸石是辉沸石族矿物中的一种,属正交晶系,化学成分主要为SiO2和Al2O3,其次为CaO。利用化学成分分析和X射线衍射分析等测试手段,深入研究了不同浓度酸处理红辉沸石的主要化学成分及晶体结构变化特征,进而揭示了红辉沸石的耐酸性。研究表明,红辉沸石的耐酸性较差,其酸稳定浓度为约5%,结构完全破坏酸浓度为15%。酸处理后可成为非晶质的高硅质矿物材料。