水浴法对工业级氢氧化镁的改性研究          下载免费PDF全文

郑小刚  李长红  李海民 《盐湖研究》2010,18(3)

水浴加热条件下,表面活性剂SDS、SLS和PEG10000的复配体改性工业级Mg(OH)2,得到了中位径(D50)1.55μm、分散性好的改性Mg(OH)2。水浴法改性Mg(OH)2的工艺条件为氢氧化镁浓度1.50 mol/L、表面活性剂用量2.50%、矿化剂氯化镁用量3.50%、水浴温度80℃、水浴时间6.0 h、搅拌速度850 r/min。  相似文献   

金属镁生产工艺进展   总被引：8，自引：0，他引：8       下载免费PDF全文

韩继龙  孙庆国 《盐湖研究》2008,16(4)

简要介绍了工业上镁的生产方法——热还原法和电解法;对热还原法和电解法的优缺点进行了讨论;概述了皮江法和电解法在改进方面所取得的新进展。  相似文献   

硫酸钾镁肥浮选尾矿热浸-冷结晶法提取七水硫酸镁工艺研究   总被引：3，自引：3，他引：0       下载免费PDF全文

李海民  雷光远  陈育刚  何勇峰 《盐湖研究》2012,20(2):44-51

以国投新疆罗布泊钾盐有限责任公司(简称国投罗钾)提供的硫酸钾镁肥浮选尾矿和氯化镁饱和卤水为原料,探索出了一条以硫酸钾镁肥浮选尾矿为原料,以氯化镁饱和溶液为浸取介质,通过中温溶浸、冷却结晶(包括盐田冷析)等工艺方法制取七水硫酸镁的工艺路线,给出了各工序的工艺技术条件及主要技术指标。  相似文献   

氯氧镁水泥及其制品的开发研究   总被引：3，自引：0，他引：3  

童义平 《盐湖研究》1996,4(1):68-72

讨论了氯氧镁水泥（简称镁水泥）及其制品的最新研究成果。作为一种新材料，该材料是有轻质、高强、无毒、阻燃等优点。对该材料的研究主要集中在对它的抗水性的改进方面和压制板的开发上。并且认为无论是制作室内装饰板，还是作为耐盐卤材料方面，镁水泥均有广阔的应用前景。  相似文献   

Carbone organique total (COT) et magnésium (Mg2+) : deux traceurs complémentaires du temps de séjour dans l'aquifère karstique     

Christelle Batiot  Christophe Emblanch  Bernard Blavoux 《Comptes Rendus Geoscience》2003,335(2):205-214

The Total Organic Carbon (TOC) is an interesting tracer of fast infiltration within karstic systems [3,7]. Regular sampling on several aquifers, from the experimental site of Vaucluse, made it possible to demonstrate the high sensitivity of this tracer compared with other commonly used chemical and isotopic tracers in karstic hydrogeology. The complementarity of magnesium, indicator of the residence time of water within the system, and TOC appears as a relevant tool in order to characterize the behaviour of the aquifer, to differentiate the water types which participate to the karstic flow (fast infiltration, unsaturated zone, saturated zone) and then, to evaluate their vulnerability.  相似文献   

Elemental composition of calcites in late Quaternary pedogenic calcretes from Gujarat, western India     

Aniruddha S. Khadkikar 《Journal of Asian Earth Sciences》2005,25(6):893-902

Pedogenic calcretes commonly exhibit clotted micrite, circum-granular calcite (grain coats) and microspar/spar veins. The three calcite-types with different dimensions were analyzed for their magnesium content to determine the relationship between crystal elongation and magnesium incorporation. The results show a very low MgO content for grain coats and microspars and high values for clotted micrite indicating that the ideal kinetic model does not hold true and several variables govern the end composition of calcites. The magnesium concentrations of meteoric calcites are genetically linked to the evolutionary history of the soil and climate. Grain coats, which are elongated calcites, contain the least amount of Mg and is related to the initial stages of pedogenesis wherein the limiting factor is the Mg/Ca ratio of the parent fluid. Lower magnesium contents arise due to smaller quantities of Mg being released during incipient weathering. Micrite morphology and composition is controlled by the greater availability of Mg ions through weathering, higher pCO₂ in soil due to increased time-dependent soil respiration, which causes a rise in calcite precipitation rates and clay authigenesis. This in turn exerts a physical control on morphology by occluding pore space and providing numerous nuclei for calcite precipitation. The wide variability in spar cements is inherently controlled by inhomogeneties in parent fluid compositions with lower-than-micrite values on account of slower precipitation rates.  相似文献   

氢氧化镁阻燃剂的研究现状   总被引：6，自引：0，他引：6       下载免费PDF全文

闫修川  李召好  李法强  马培华 《盐湖研究》2005,13(3):58-61

通过分析氢氧化镁作为阻燃剂的优缺点,评述了现阶段对氢氧化镁的改性应用,并提出了今后氢氧化镁阻燃剂的发展趋势。  相似文献   

纳米氢氧化镁的制备   总被引：1，自引：0，他引：1       下载免费PDF全文

胡章文  汪兵  单承湘  陶庭先 《盐湖研究》2005,13(4):47-50

以氯化镁和氢氧化钠为原料,添加表面活性剂,直接利用表面活性剂在固/液界面的“双亲性”使其吸附在新生成的氢氧化镁微粒上,制备纳米氢氧化镁。并采用X-射线和透射电镜等对样品进行表征,结果表明样品晶型发育完善,样品为片状、粒径为85 nm、粒度均匀且分散性好的纳米氢氧化镁粉体。  相似文献   

CO₂-driven cation leaching after tropical forest clearing     

Daniel Markewitz  Ricardo de O. Figueiredo  Eric A. Davidson 《Journal of Geochemical Exploration》2006,88(1-3):214

The objective of this study was to investigate the role of dissolved CO₂ (H₂CO₃*) as a mechanism of cation removal from surface soils under secondary land uses in the tropics. Soil leachate columns were prepared with 0–10 cm soils from mature and secondary forest, and managed pastures, and extracted with H₂CO₃* from deionized water equilibrated with 0%, 0.5%, 1%, and 10% CO₂ (g). Extraction of soil cations slowed over time following an exponential form for the cumulative data. The rate of cation concentration decline varied as a function of CO₂ concentration with the 10% solution resulting in a greater percent decline with extraction volume. Potassium removal from the exchange sites of all soils and for all solutions was nearly complete ranging from 85% to 97% while removals of Mg (31% to 71%) and Ca (12% to 42%) were lower. The asymptotic patterns of cation loss observed in this study suggest that H₂CO₃* acid-driven losses of cations may become self-limiting over time. Other stronger acids from atmospheric deposition or organic sources may serve to perpetuate cation removal, and re-forestation on these cleared lands would certainly re-distribute cations from soils to vegetation.  相似文献   

共沸蒸馏置换干燥法制备纳米氧化镁粉体的研究   总被引：2，自引：0，他引：2       下载免费PDF全文

王宝和  张伟  张文博  范方荣 《盐湖研究》2006,14(3):34-38

以六水氯化镁和尿素为原料,采用均匀沉淀法制备出氢氧化镁沉淀,利用不同共沸蒸馏置换干燥法除去沉淀中的湿分,再将干燥的氢氧化镁粉体经马弗炉煅烧得到纳米氧化镁粉体;通过透射电子显微镜和X射线衍射仪的表征与分析,研究不同共沸蒸馏置换干燥法对纳米氧化镁粉体形貌、颗粒尺寸和团聚情况的影响;探讨了共沸蒸馏置换干燥的基本原理、操作方法和置换剂的选择原则。  相似文献