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Investigation of the Petrological and Geochemical Characteristics of siderite in the Early Cretaceous Sandstone of Lacustrine Sedimentary Sequence in the Erlian Basin from Northeastern China

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Journal of Geoscience and Environment Protection 2024年第6期12卷 305-321页

作者： Yunlong Zhang Mingming Tian Huili Xie Xide Li Wusheng Liu Shiqi Ni Beijing Research Institute of Uranium Geology Beijing China

siderite is a prevalent authigenic mineral in siliciclastic rocks, which usually occurred in eodiagensis period and could be used as an indicator of sedimentary environment. Some siderite precipitated in burial depth with geochemical information of basin fluid evolution. The crystal morphology, geochemical composition, and isotope values are influenced by physical and geochemical environment of precipitation. In this study, samples from the Early Cretaceous of Erlian basin in the northwestern China were collected, and mineralogy, bulk and in-situ geochemistry, C and O isotopes were analyzed to comprehensively investigate the sedimentary and diagenetic environment that the sediments experienced. Six lithofaices with three types of crystal habits were recognized in the siderite-rich sandstone, bundle crystal in spherical forms, blocky rhombs in intergranular pore and cleavage of muscovite, and micro bundle and mosaic crystals aggregates in nodular. The siderite growth proceeds through micro bundle and mosaic crystals to bundle siderite aggregates and then into blocky rhombs. The crystal evolution is also reflected by geochemical composition. The micro bundle and mosaic crystals are Casiderite. The spheritic shaped bundle aggregates are Ca-Mn-siderite. The blocky rhomb siderite shows gray part and bight part with Ca, Mg and Mn varies. Increase of Ca in block rhomb siderite suggests burial and mesodiagenesis, the high content of Mn may have linkage with eogenetic effects. The relatively positive and slightly negative δ13C value indicates meteoric water domination and influence of organic matter evolution in shallow buried time. The narrow ranges negative δ18O value suggest a small span of temperature of siderite formation.

关键词： siderite Sedimentary Environment Lacustrine Deposition Early Cretaceous Erlian Basin

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Catalytic performance and reaction mechanisms of NO removal with NH_(3) at low and medium temperatures on Mn-W-Sb modified siderite catalysts

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Journal of Environmental Sciences 2022年第5期34卷 126-139页

作者： Guihuan Yao Yuliang Wei Keting Gui Xiang Ling School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211816China School of Energy and Environment Southeast UniversityNanjing 210096China

Iron-based catalysts have been explored for selective catalytic reduction(SCR)of NO due to environmentally benign characters and good SCR activity.Mn-W-Sb modified siderite catalysts were prepared by impregnation method based on siderite ore,and SCR perfor-mance of the catalysts was investigated.The catalysts were analyzed by X-ray diffrac-tion,H_(2)-temperature-programmed reduction,Brunauer-Emmett-Teller,Thermogravimetry-derivative thermogravimetry and in-situ diffused reflectance infrared Fourier transform spectroscopy(DRIFTS).The modified siderite catalysts calcined at 450℃ mainly consist of Fe_(2)O_(3),and added Mn,W and Sb species are amorphous.3Mn-5W-1.5Sb-siderite catalyst has a wide temperature window of 180-360℃ and good N_(2) selectivity at low temperatures.In-situ DRIFTS results show NH_(4)^(+),coordinated NH_(3),NH_(2),NO_(3)^(-)species(bidentate),NO_(2)-species(nitro,nitro-nitrito,monodentate),and adsorbed NO_(2) can be discovered on the sur-face of Mn-W-Sb modified siderite catalysts,and doping of Mn will enhance adsorbed NO_(2) formation by synergistic catalysis with Fe^(3+).In addition,the addition of Sb can inhibit sulfates formation on the surface of the catalyst in the presence of SO_(2) and H_(2)O.Time-dependent in-situ DRIFTS studies also indicate that both of Lewis and Br?nsted acid sites play a role in SCR of NO by ammonia at low temperatures.The mechanism of NO removal on the 3Mn-5W-1.5Sb-siderite catalyst can be discovered as a combination of Eley-Rideal and Langmuir-Hinshelwood mechanisms with three reaction pathways.The mechanism of NO,oxidized by synergistic catalysis of Fe^(3+)and Mn^(4+/3+)to form NO_(2) among three pathways,reveals the reason of high NO_(x) conversion of the catalyst at medium and low temperatures.

关键词： Iron-based catalysts Mn-W-Sb In-situ diffused reflectance infrared Fourier transform spectroscopy Reaction mechanism siderite Low and medium temperature

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Reaction behavior and non-isothermal kinetics of suspension magnetization roasting of limonite and siderite

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International Journal of Minerals,Metallurgy and Materials 2023年第5期30卷 824-833页

作者： Qiang Zhang Yongsheng Sun Yuexin Han Yanjun Li Peng Gao School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China National-local Joint Engineering Research Center of High-efficient exploitation technology for Refractory Iron Ore Resources Shenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

In order to develop limonite and decrease CO_(2) emissions,siderite is proposed as a clean reductant for suspension magnetization roasting(SMR) of limonite.An iron concentrate(iron grade:65.92wt%,iron recovery:98.54wt%) was obtained by magnetic separation under the optimum SMR conditions:siderite dosage 40wt%,roasting temperature 700℃,roasting time 10 min.According to the magnetic analysis,SMR achieved the conversion of weak magnetic minerals to strong magnetic minerals,thus enabling the recovery of iron via magnetic separation.Based on the phase transformation analysis,during the SMR process,limonite was first dehydrated and converted to hematite,and then siderite decomposed to generate magnetite and CO,where CO reduced the freshly formed hematite to magnetite.The microstructure evolution analysis indicated that the magnetite particles were loose and porous with a destroyed structure,making them easier to be ground.The non-isothermal kinetic results show that the main reaction between limonite and siderite conformed to the two-dimension diffusion mechanism,suggesting that the diffusion of CO controlled the reaction.These results encourage the application of siderite as a reductant in SMR.

关键词： reaction behavior non-isothermal kinetics suspension magnetization roasting siderite limonite CO_(2)emissions

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Mechanism of high temperature reduction on iron carbide preparation with low-grade siderite

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Journal of Iron and Steel Research(International) 2022年第9期29卷 1357-1367页

作者： Dong Chen Ya-nan Lv Wei Zhao Fei-bao Wu Wei-ang Ying School of Iron and Steel Soochow UniversitySuzhou 215021JiangsuChina Department of Mechanical and Electrical Engineering Suzhou Institute of Industrial TechnologySuzhou 215104JiangsuChina

The carburization roasting followed by magnetic separation is a feasible method to utilize low-grade siderite ore.In order to enhance the carburization efficiency and separation effciency,high temperature reduction was carried out,and its mechanism was demonstrated by measuring carburization index,phase change,and microstructure under a carbon-sulfur infrared analyzer,an X-ray diffractometer,and a metallurgical microscope.The results show that both the carburization effciency of siderite pellet and the separation efficiency of iron carbide from gangue are very low.However,high temperature reduction is a useful way to enhance the carburization efficiency,as it can accelerate the reduction reaction rate and carburization reaction rate.Furthermore,high temperature reduction can improve the growth of iron carbide particle,promote the carburization efficiency,and strengthen the sodium modification reactions,thereby greatly accelerating the separation efficiency of iron carbide and gangue.When the siderite pellets were reduced at 1050℃ for 90 min and carburized at 650℃ for 120 min,the carburization index of carburized pellets reached 36.06.After magnetic separation treatment,an electric furnace burden assaying 83.12 wt.%Fe and 6.96 wt.%C was prepared,and the corresponding iron recovery rate was 95.43%.The high temperature reduction is promisingly adopted to promote the utilization of low-grade siderite ores using carburization-magnetic separation technology.

关键词： siderite High temperature reduction Carburization-Separation Iron carbide

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Fluidized magnetization roasting of refractory siderite-containing iron ore via preoxidation-low-temperature reduction

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International Journal of Minerals,Metallurgy and Materials 2023年第6期30卷 1057-1066页

作者： Haoyan Sun Zheng Zou Meiju Zhang Dong Yan Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China Institute of Process Engineering Chinese Academy of SciencesState Key Laboratory of Multiphase Complex SystemsBeijing 100190China University of Chinese Academy of Sciences School of Chemical EngineeringBeijing 100049China

Magnetization roasting is one of the most effective way of utilizing low-grade refractory iron ore.However,the reduction roasting of siderite(FeCO3)generates weakly magnetic wüstite,thus reducing iron recovery via weak magnetic separation.We systematically studied and proposed the fluidized preoxidation-low-temperature reduction magnetization roasting process for siderite.We found that the maghemite generated during the air oxidation roasting of siderite would be further reduced into wüstite at 500 and 550℃due to the unstable intermediate product magnetite(Fe_(3)O_(4)).Stable magnetite can be obtained through maghemite reduction only at low temperature.The optimal fluidized magnetization roasting parameters included preoxidation at 610℃for 2.5 min,followed by reduction at 450℃for 5 min.For roasted ore,weak magnetic separation yielded an iron ore concentrate grade of 62.0wt%and an iron recovery rate of 88.36%.Compared with that of conventional direct reduction magnetization roasting,the iron recovery rate of weak magnetic separation had greatly improved by 34.33%.The proposed fluidized preoxidation-low-temperature reduction magnetization roasting process can realize the efficient magnetization roasting utilization of low-grade refractory siderite-containing iron ore without wüstite generation and is unlimited by the proportion of siderite and hematite in iron ore.

关键词： magnetization roasting fluidization siderite preoxdization low-temperature reduction

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Mesoproterozoic biomineralization:Cyanobacterium-like filamentous siderite sheaths~1.4 Ga

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Journal of Palaeogeography 2023年第3期12卷 384-400页

作者： Dong-Jie Tang Xiao-Ying Shi Xi-Qiang Zhou Robert Riding State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences(Beijing)Beijing 100083China Institute of Earth Sciences China University of Geosciences(Beijing)Beijing 100083China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Earth and Planetary Sciences University of TennesseeKnoxvilleTN 37996-1526USA

Biomineralization was a key development in a wide variety of organisms,yet its history prior to the Ediacaran remains poorly understood.In this paper,we describe~1420-1330 million year old microscopic tubes preserved as siderite(FeCO_(3)).In size and shape these tubes closely resemble cyanobacterial sheaths forming mineralized mats.We consider two competing explanations for their formation.First,the tubes and associated sediment were originally composed of Ca-carbonate that was subsequently replaced by siderite.In this case,siderite mineralization was early,but post-mortem,as in early silicification,and preferentially preserved the more resilient sheath.However,no relict calcite is observed.Second,the Fe-carbonate mineralogy of the tubes and sediment is synsedimentary.In this case,photosynthetic oxygen may have precipitated Fe-oxyhydroxide that was promptly converted to siderite by dissimilatory iron reduction(DIR).Primary siderite mineralization of cyanobacteria has not been described before.Both explanations link photosynthetic processes to preferential sheath mineralization during the life of the cyanobacteria,as observed in present-day calcified cyanobacteria.This process might include CO_(2)-concentrating mechanisms(CCMs)linked to relatively low levels of atmospheric CO_(2),consistent with empirical estimates of mid-Proterozoic CO_(2)levels based on paleosols and weathering rinds.In either case,these cyanobacterium-like fossils preserved in siderite provide an early example of biomineralization and suggest the interactive in-fluences of both metabolic processes and ambient seawater chemistry.

关键词： Xiamaling Formation siderite Ferruginous Dissimilatory iron reduction(DIR) Iron formation(IF) CO_(2)-concentrating mechanism(CCM)

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Sorption mechanisms of diphenylarsinic acid on natural magnetite and siderite:Evidence from sorption kinetics,sequential extraction and extended X-ray absorption fine-structure spectroscopy analysis

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Frontiers of Environmental Science & Engineering 2022年第9期16卷 39-52页

作者： Meng Zhu Yuhuan He Xiaobao Wei Haoran Qi Yunpeng Zhang Yijun Zhang Ruyi Yang Yongming Luo School of Ecology and Environment Anhui Normal UniversityWuhu 241002China Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China Anhui Provincial Engineering Laboratory of Water and Soil Pollution Control and Remediation Anhui Normal UniversityWuhu 241002China Center of Cooperative Innovation for Recovery and Reconstruction of Degraded Ecosystem in Wanjiang City Belt Anhui Normal UniversityWuhu 241002China

Diphenylarsinic acid(DPAA)is both the prime starting material and major metabolite of chemical weapons(CWs).Because of its toxicity and the widespread distribution of abandoned CWs in burial site,DPAA sorption by natural Fe minerals is of considerable interest.Here we report the first study on DPAA sorption by natural magnetite and siderite using macroscopic sorption kinetics,sequential extraction procedure(SEP)and microscopic extended X-ray absorption fine-structure spectroscopy(EXAFS).Our results show that the sorption pseudo-equilibrated in 60 minutes and that close to 50%and 20%–30%removal can be achieved for magnetite and siderite,respectively,at the initial DPAA concentrations of 4–100 mg/L.DPAA sorption followed pseudo-secondary and intra-particle diffusion kinetics models,and the whole process was mainly governed by intra-particle diffusion and chemical bonding.SEP and EXAFS results revealed that DPAA mainly formed inner-sphere complexes on magnetite(>80%),while on siderite it simultaneously resulted in outer-sphere and inner-sphere complexes.EXAFS analysis further confirmed the formation of inner-sphere bidentate binuclear corner-sharing complexes(^(2)C)for DPAA.Comparison of these results with previous studies suggests that phenyl groups are likely to impact the sorption capacity and structure of DPAA by increasing steric hindrance or affecting the way the central arsenic(As)atom maintains charge balance.These results improve our knowledge of DPAA interactions with Fe minerals,which will help to develop remediation technology and predict the fate of DPAA in soil-water environments.

关键词： Diphenylarsinic acid(DPAA) Sorption Magnetite siderite Sequential extraction EXAFS

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Mechanism of improved magnetizing roasting of siderite–hematite iron ore using a synergistic CO–H2 mixture

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Journal of Iron and Steel Research(International) 2020年第1期27卷 12-21页

作者： Qiang Zhao Ji-lai Xue Wen Chen School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Changsha Research Institute of Mining and Metallurgy Co. Ltd.Changsha 410083HunanChina

A fluidized-bed magnetizing roasting-magnetic separation process was selected to treat this type of material.Phase transformations and microstructural changes in the product resulting from magnetizing roasting under different reducing gases(CO,H2,CO+H2)were clarified by vibrating sample magnetometry,X-ray diffraction,scanning electron microscopy,and energy-dispersive X-ray spectroscopy.The results indicated that the conversion ratio and saturation magnetization of samples roasted in a mixed gas of CO and H2 were higher than those of samples produced under CO or H2 alone.This indicated that synergy of the combined CO and H2 gas had a positive effect on the fluidized-bed magnetizing roasting process.The mechanism and kinetics of the improved magnetizing roasting of a siderite-hematite iron ore mixture under this synergistic CO-H2 system were investigated under isothermal conditions.The results indicated that the apparent activation energies of the reactions of the iron oxides decreased from 37.7 and 17.9 to 15.9 kJ/moI when the roasting atmosphere was changed from pure H2 or CO to a gas mixture of CO and H2,respectively.The mixed CO-H2 gas promoted the conversion ratio of hematite and siderite to magnetite,thereby improving the conversion ratio in the fluidized-bed magnetizing roasting process.

关键词： siderite Hematite Mixed iron ore Fluidized-bed magnetizing roasting Kinetics Magnetite

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Effect and mechanism of siderite on reverse flotation of hematite

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International Journal of Minerals,Metallurgy and Materials 2016年第4期23卷 373-379页

作者： Wan-zhong Yin Dong Li Xi-mei Luo Jin Yao Qian-yu Sun College of Resources and Civil Engineering Northeastern University College of Zijin Mining Fuzhou University Faculty of Land Resource Engineering Kunming University of Science and Technology

The effects of siderite on reverse flotation of hematite were investigated using micro flotation, adsorption tests, and Fourier transform infrared spectroscopy. The flotation results show that interactions between siderite and quartz are the main reasons that siderite significantly influences the floatability. The interactions are attributed to dissolved siderite species and fine siderite particles. The interaction due to the dissolved species is, however, dominant. Derjaguin-Landau-Verwey-Overbeek（DLVO） theoretical calculations reveal that adhesion on quartz increases when the siderite particle size decreases and that fine particles partly influence quartz floatability. Chemical solution calculations indicate that the dissolved species of siderite might convert the surface of active quartz to CaCO_3 precipitates that can be depressed by starch. The theoretical calculations are in good agreement with the results of adsorption tests and FTIR spectroscopy and explain the reasons why siderite significantly influences reverse flotation of hematite.

关键词： hematite siderite reverse flotation solution chemistry

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Mineralogical alteration of thermally treated siderite in air: Mossbauer spectroscopy results

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Chinese Science Bulletin 1999年第18期44卷 1712-1717页

作者： Pan, YX Zhu, RX Ping, JY Chinese Acad Sci Inst Geophys Beijing 100101 Peoples R China Beijing Univ Sci & Technol Dept Phys Mat Beijing 100083 Peoples R China

Mineralogical alternation of thermally treated siderite in air atmosphere has been systematically analyzed by Mossbauer effects. It was preliminarily estimated from the area of sub-spectra that 4% , 39% and 62% of magnetite were formed at 410℃, 490℃ and 510℃ respectively. After being incrementally heated at 530℃ the spectra consist of two sextets of Fe3O4. Sextet of γ-Fe2O3 with hyperfine field of 50T was observed at 550℃. Spectra at 580℃

关键词： siderite mineralogical phase transition thermally treated in air.

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