Spatio-temporal distribution of dissolved sulfide in China marginal seas

With sulfide increasingly recognized as an important parameter to assess the oxidation-reduction level in aqueous enviromnent, research on its geochemical behavior is becoming important. Water samples collected in Bohai Sea （1-19 August, 2010）, Yellow Sea （20-30 November, 2010） and East China Sea （3-17 June, 2010 and 1-10 November, 2010） were used to determine the occurrence and distribution of dissolved sulfide by methylene blue spectrophotometric method. Results show that： （1） horizontally, concentration of dissolved sulfide significantly varied from the coastal region to the open sea and profoundly influenced by physical processes. High values occurred in the river-sea boundary zone ＂marginal filter＂ due to rich riverine input, frequent upwelling and active exchange in shelf edge. Terrestrial input from adjacent rivers and the current cycling contributed to the high sulfide appeared in western Bohai Sea, eastern Shandong Peninsula, and northeast of Changjiang （Yangtze） River estuary. Especially, relative higher sulfide values occurred in Yellow Sea, which is consistent with the variation of salinity largely due to the hydrodynamic feature; （2） vertically, measurement of dissolved sulfide in bottom water was higher and more variable than that in surface water caused by the wind-induced resuspension and dissimilatory sulfate reduction. Moreover, nutrient-type profile clearly identified that oxidation plays a major role in the biogeochemistry cycle of sulfide in water; （3） seasonally, investigation for East China Sea in June and November reflected seasonal variation of Changjiang River Diluted Water, Kuroshio Current, and Taiwan Warm Current. Concentration in June was much higher than that sampled in November at most stations. Mean concentration of dissolved sulfide varied seasonally from 2.26 μg/L （June） to 1.16 μg/L （November） in surface and 3.00 μg/L （June） to 1.56 μg/L （November） in bottom. Progress in the field is slow and more effort is needed to ensure the accuracy and reliability of determination and estimate the natural or anthropogenic contribution of dissolved sulfide in ecosystems.

Mechanochemical sulfidization of a mixed oxide-sulphide copper ore by co-grinding with sulfur and its effect on the flotation efficiency

Mechanochemical sulfidization of a mixed sulfide/oxide copper ore by co-grinding with sulfur and additives including Mg(NO3)2 and Fe(NO3)3 salts and iron,aluminum and magnesium powders was investigated for the first time.Also,the influence of sulfidization during the wet-milling process was examined on the separation efficiency and recovery of copper in detail.The results demonstrated that co-grinding with sulfur solely had the best flotation performance at the value of 0.5 wt.%and it was attributed to the possible existence of S\\O bonding on copper oxides surfaces.In addition,adding magnesium nitrate salt,magnesium powder,iron nitrate salt and aluminum powder as additive associated with 0.5 wt%sulfur into ball milling caused the flotation improvement at the amounts of 0.2 wt%,0.2 wt%,0.5 wt%and 0.5 wt%,respectively.Also,the effect of grinding time and sulfidization pH with 0.5 wt%sulfur solely was determined and pH s of 7.5 to 8.5 gave the best results.The highest recovery(75.76%)and separation efficiency(63.44%)were achieved at pH of 7.5 and 8.5,respectively.

Study on experiment and mechanism of thermal dissolved sulfuration of low grade lead-zinc oxide ore in lanpin

The thermal dissolved sulfuration technology is brought forward and performed based on the characteristic of low grade lead-zinc oxide ore in lanpin. Using sulfur as the sulphidizing agent in the experiment, the oxides in the sandstone and ignimbrite are changed into sulfides. The disproportionation reaction of sulfur in a solution is confirmed as 4S＋3H2O=2S^2-＋S2O3^2--＋6H^＋. The dynamics process is studied and the first-order reaction rate equation -1n（1-a）=ktt is obtained. The effects of the reactive products, stirring speed, dosage of sulfuration agent, value of pH and sulphidizing temperature on the sulfuration of oxide ore are investigated. The results indicate that the reactive apparent activation energy is 100.8 kJ/mol and the sulfuration ratio of lead-zinc oxide ore reaches 60% under the conditions of pH 5.9-7.5, the sulfuration temperature of 130 ℃, sulfuration time of 180 min and the stirring speed of 800 r/min.

Isotopic Composition of Dissolved Carbonates Meromictic Soda Lake Doroninskoe(Eastern Transbaikalia,Russia)

1 Introduction Meromictic soda Lake Doroninskoe localized in the intermountain area,filled with continental sediments of the Mesozoic,in the upper basin of the river Amur.Coordinates of its location are N51°14’42"E112°14’40",

Leaching of complex sulphide concentrate in acidic cupric chloride solutions

The chemical analysis of a complex sulphide concentrate by emission spectrometry and X-ray diffraction shows that it contains essentially copper, lead, zinc and iron in the form of chalcopyrite, sphalerite and galena. A small amount of pyrite is also present in the ore but does not be detected with X-ray diffraction. The cupric chloride leaching of the sulphide concentrate at various durations and solid/liquid ratios at 100 ℃ shows that the rate of dissolution of the ore is the fastest in the first several hours, and after 12 h it does not evolve significantly. If oxygen is excluded from the aqueous cupric chloride solution during the leaching experiment at 100 ℃, the pyrite in the ore will not be leached. The determination of principal dissolved metals in the leaching liquor by flame atomic absorption spectrometry, and the chemical analysis of solid residues by emission spectrometry and X-ray diffraction allow to conclude that the rate of dissolution of the minerals contained in the complex sulphide concentrate are in the order of galena >sphalerite>chalcopyrite.

硫化—胺法浮选菱锌矿体系中两相和三相泡沫的性能研究

硫化—胺法是氧化锌的主要选别方法之一,在工业生产中的指标较好,但存在浮选泡沫发黏、难消泡的问题。研究了硫化-胺法浮选菱锌矿体系中两相泡沫和三相泡沫的性能,考察了硫化钠用量、十二胺用量、矿物含量、矿物粒度、矿物种类等对泡沫稳定性的影响,并测试了不同矿物含量的矿浆黏度。结果表明,在采用硫化—胺法浮选菱锌矿时,加入硫化钠能够提高两相和三相泡沫的稳定性。不同粒度的矿物颗粒对泡沫稳定性影响不同,加入-74+37μm粒级的菱锌矿和石英颗粒均能够降低泡沫稳定性,而加入-37μm粒级的菱锌矿和石英颗粒均能够提高泡沫稳定性,-18μm的石英颗粒影响尤为明显。当十二胺与微细粒级石英共同存在时,浮选泡沫尤为稳定。加入石英颗粒后的三相泡沫半衰期均高于菱锌矿,这是由于石英矿浆的黏度高于菱锌矿,因而泡沫液膜的Marangoni效应增强,导致排液速率变慢,泡沫液膜变薄速率下降,泡沫稳定性更强。

阴阳离子在铜、铅、锌氧化矿硫化浮选中的强化作用研究现状及展望

硫化浮选法是回收铜、铅、锌氧化矿常用的浮选工艺。为获得更高的回收率,研究人员常使用一些阴阳离子对硫化过程进行强化。文章通过对近些年铜、铅、锌氧化矿强化硫化浮选相关研究成果的梳理,阐述了铜、铅、锌氧化矿硫化浮选机制,讨论了铵根离子、铅离子、铜离子、锌离子、氟离子、氯离子、碳酸根离子等阴阳离子的强化机理,综述了其强化硫化基础理论研究的进展,并对未来发展方向进行了展望,以期对铜、铅、锌氧化矿强化硫化浮选的研究提供一定的帮助。

矿石中硫赋存状态分析方法

采用传统法对贵州回龙矿石进行试验,测得矿石中硫磺、硫酸盐及硫化物的质量分数分别为0.42%、0.13%、3.10%,而采用MLA仪器该矿石进行分析,结果显示矿石中硫化物占95%,几乎没有硫磺.这表明传统的硫赋存状态分析方法无法准确测定该矿石中的硫磺、硫化物的含量.针对传统检测方法对硫磺、硫化物的分析误差较大的问题,提出了先用四氯乙烯来萃取矿石中的硫磺,然后用碳酸钠溶液浸出硫酸盐,最后分两步浸出硫化物的分相流程的新方法.改进的新方法测得矿石中硫磺、硫酸盐及硫化物的质量分数分别为0.04%、0.13%、3.48%,该结果跟仪器测试结果非常吻合,表明该新方法准确度高,也适用于含有重晶石的矿石中硫赋存状态的分析.

废水中硫化物生物净化影响因素的研究

在 上流式填 料 床 反应 器 中，利 用 无色 硫 细 菌处 理 废水 中 的 硫化 物， 当硫 化 物 浓度 为 ２９３ ～３１０ ｍ ｇ／ Ｌ、反应器容 积负荷为５ｋｇ／ ｍ ３·ｄ 、溶解氧为 ３２ ｍ ｇ／ Ｌ 时，硫化物 去除率可 达到９２ ％ ～９５ ％ ，去除的硫化物中９４ ％ ～９６ ％ 转化为 Ｓ。试验结果表明：溶解氧是影响

适用于海洋沉积物间隙水中氧、锰(Ⅱ)、铁(Ⅱ)、硫分析的金汞齐微电极

用电化学方法在金微电极的基础上制成金汞齐微电极。研究了电极预处理方法、电镀以及强极化金汞齐微电极的条件、电极的校正方法以及实际测量电化学参数的选择等。采用三电极体系和方波伏安法,金汞齐微电极(vs.SCE)从-0.10～-1.75V电势范围内可同时测定沉积物间隙水中的溶解氧、Mn2+、Fe2+和S2-等氧化还原物的浓度。实验结果表明金汞齐微电极对溶解氧、Mn2+、Fe2+和S2-的灵敏度和检出限分别为0.16nA/(μmol/L)、6μmol/L,0.35nA/(μmol/L)、3μmol/L,0.22nA/(μmol/L)、5μmol/L和34nA/(μmol/L)、0.03μmol/L。在连续测定15个沉积物样品后,重新校正电极,测量相对误差<3%。

硫酸盐制浆过程中硫的分布与变化规律

本文研究了兴安落叶松硫酸盐制浆过程中流在蒸煮液、溶出木素和残余木素中的分布及变化情况。结果表明，蒸煮过程中蒸煮液的活性碱和硫化钠浓度不断下降，硫化度则不断上升，活性碱与硫化钠的消耗主要发生在初始脱水素阶段．溶出木素的含硫量在初始脱木素阶段量最高，随着蒸煮反应的进行，其百分含量逐渐下降，但绝对量却不断上升。蒸煮结束时，约占总用硫量1／5的硫与溶出木素结合在一起。木片或纸浆的含硫量与木素的硫化速率和残余木素的含量密切相关。在残余脱木素阶段，残余木素的硫化对木素的说除已没有促进作用。

THPS溶解油罐中的硫化亚铁

用THPS(四羟甲基硫酸磷)配合氯化铵清除油罐中沉积的硫化亚铁,介绍了THPS在溶解硫化亚铁方面的实验结果,包括THPS与氯化铵的质量配比,溶解液的浓度和酸度,以及反应温度、反应时间。结果表明,THPS与氯化铵质量比为6.5:0.6,温度为80℃,pH=5,反应时间为8 h时,THPS溶解硫化亚铁的效果最好。溶解液质量分数为14.0%时,硫化亚铁溶解率可达到92.50%。

硫化物废水的生物处理技术研究

生物脱硫工艺与传统工艺相比,具有明显的优越性。文章介绍了硫化物废水的各种处理技术、特点及原理,综述了国内外生物脱硫的研究现状,重点阐述了硫化物废水生物处理的几个重要的影响因素:溶解氧、pH值、硫化物负荷、反应器及填料的类型,指出利用基因工程技术构建的新型工程菌株将具有更好的脱硫效果。

基于Thiobacillus thioparus菌株的生物脱硫工艺参数优化研究

文章研究采用生物脱硫工艺利用生物滴滤池,以异养脱硫菌Thiobacillus thioparus为菌株,分别研究了以陶粒、火山岩、活性炭为滴滤池滤料条件下溶解氧,硫化物负荷,气液体积比,pH值等生物脱硫工艺参数对H2S去除效果的影响。实验结果表明:溶解氧影响Thiobacillus thioparus菌株对硫化物的去除率,通过单因素实验发现,当硫化物负荷为80 g·m^-3h^-1,DO为1.5 mg·L^-1时,硫化物去除率达80%以上,单质硫回收率最大;硫化物负荷对H2S去除有影响并且与DO呈线性关系;循环液pH值为8.5时,沼气中S2-去除率达94.3%,此时单质硫转化率大于SO42-的转化率;当沼气中H2S浓度为4200±14 mg·m^-3、气液比为15∶1时,硫化物去除率达93.9%。在不同反应条件下,利用3种滤料填充滴滤池,其中活性炭的去除效果均优于其他两种滤料,陶粒和火山岩效果差别不大。

废水循环法合成硫化异丁烯的工艺研究

采用两步脱硫脱氯法合成硫化异丁烯,第2步反应产生的废水回用于下一批的第1步反应,第1步控制异丙醇投加量为1.33 mol/mol[S2Cl2],硫化钠投加量为0.70～0.72 mol/mol[S2Cl2];第2步控制硫化钠投加量为0.24～0.34 mol/mol[S2Cl2]。试验结果表明,采用废水循环法合成硫化异丁烯,其产品质量能达到国内外同类产品标准。

四羟甲基季鏻盐:一种新型多功能油田化学剂

本综述包含4个论题:①四羟甲基季盐(氯化物、硫酸盐、磷酸盐及醋酸盐等,简称THP+盐)的结构、化学性质及环保性;②由酸、甲醛、磷化物制THP+盐的工艺流程,使用的原料,催化剂,生产安全问题及普遍使用的THP+盐———硫酸盐(THPS);③THP+盐的杀菌活性,THPS作为广谱、高效、无泡沫、具环保性的杀菌剂,在北海丹麦区块Skjold酸性油田用于杀灭井下、储层SRB菌的试验结果;④THP+盐用作硫化亚铁垢清除剂,THP+盐与铵根离子、硫化亚铁形成水溶性金属络合物及其条件,胺基磷酸、胺基醋酸与THPS复配的溶垢剂及其应用。图2表1参19。

预处理硫酸盐制浆溶出木质素的结构特性

用元素分析、1 H -NMR和1 3C -NMR波谱比较了硫化钠预处理硫酸盐制浆和常规硫酸盐制浆溶出木质素的化学结构。结果表明 ,预处理制浆溶出木质素的硫元素与甲氧基含量及脱木质素反应均不同于常规硫酸盐制浆。

H_2S在重质原油中的溶解特性研究

塔河油田12区原油属高含硫、高黏度、高凝点的特超稠油,在生产集输和运输环节,溶解在稠油中的H2S不断析出,会带来严重的安全隐患。以塔河12区稠油中H2S的溶解特性为研究对象,研制了稠油中H2S溶解度测试装置,实验分析了温度、压力、含水及油品物性对稠油中H2S含量的影响,结果表明稠油中的H2S溶解度随温度的升高,压力的降低和含水的减少而减少,同时随原油密度减小而减小。实验结果可为重质原油H2S的脱除工艺提供技术支持,为集输系统H2S的安全运行提供指导。

常压法间位聚芳硫醚酰胺酰胺的合成及表征

通过合成一种新的含二酰胺键的单体,将其与硫化钠进行常压溶液缩聚,合成出了间位聚芳硫醚酰胺酰胺(m-PPSAA),通过红外、核磁证实了其化学结构,用DSC、TG等手段对m-PPSAA的热性能进行了表征,结果表明聚合物具有优良的热性能,通过X射线衍射表明m-PPSAA为结晶型聚合物,通过溶解性试验表明m-PPSAA能溶解于DMF、DMSO、NMP等溶剂,比PPS的溶解性好。

用活性炭纤维同时脱除二氧化碳中COS与H_2S的研究

采用固定床动态吸附实验考察了用NaOH、KOH、Na2CO3、K2CO3和Fe3+、CO2+等对活性炭纤维(ACF)进行改性,并分别对其脱除氧硫化碳(COS)和硫化氢(H2S)的性能进行了测试。重点是以N2和CO2为稀释气,对改性离子的种类、含量、反应气氛和反应温度等的脱硫性能进行研究,还考察了在COS和H2S同时存在的情况下,ACF脱除COS和H2S的性能。结果表明,碱改性ACF比空白ACF脱除效果好,金属离子改性ACF与碱改性ACF相比可以有效地提高活性炭纤维的硫容量。其中,用CO2+改性ACF能同时提高脱除COS和H2S的效果。