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Effect of ammonium sulfate on the formation of zinc sulfide species on hemimorphite surface and its role in sulfidation flotation

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International Journal of Minerals,Metallurgy and Materials 2023年第11期30卷 2147-2156页

作者： Xi Zhang Yu Wang Jiushuai Deng Zhongyi Bai Hongxiang Xu Qingfeng Meng Da Jin Zhenwu Sun Key Laboratory of Separation and Processing of Symbiotic-Associated Mineral Resources in Non-ferrous Metal Industry School of Chemical and Environmental EngineeringChina University of Mining and Technology(Beijing)Beijing 100083China Inner Mongolia Research Institute China University of Mining and Technology(Beijing)Ordos 017001China State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming 650093China Engineering Technology Research Centre for Comprehensive Utilization of Rare Earth Rare Metal and Rare-Scattered in Non-ferrous Metal IndustryChina University of Mining and Technology(Beijing)Beijing 100083China

Effectively strengthening the surface sulfidation is essential for recovering hemimorphite by froth *** this work,inductively coupled plasma optical emission spectrometer(ICP-OES)measurements,Visual MINTEQ calculation,X-ray photoelectron spectroscopy(XPS)analysis,time of flight secondary ion mass spectrometry(ToF-SIMS)analysis,and micro-flotation experiments were explored to systematically investigate the effect of ammonium sulfate((NH_(4))_(2)SO_(4))on the formation of zinc sulfide species on hemimorphite surface and its role in sulfidation *** results showed that(NH_(4))_(2)SO_(4)exhibited a positive influence on hemimorphite sulfidation *** was ascribed to the number of zinc components in the form of Zn^(2+)and[Zn(NH_(3))_(i)]^(2+)(i=1–4)increased in the flotation system after hemimorphite treatment with(NH_(4))_(2)SO_(4),which was beneficial to its interaction with sulfur species in solution,resulting in a dense and stable zinc sulfide layer generated on the hemimorphite surface.[Zn(NH_(3))_(i)]^(2+)participated in the sulfidation reaction of hemimorphite as a transition *** addition the sulfidation reaction of hemimorphite was accelerated by(NH_(4))_(2)SO_(4).Thus,(NH_(4))_(2)SO_(4)presents a vital role in promoting the sulfidation of hemimorphite.

关键词： hemimorphite sulfidation ammonium sulfate zinc sulfide species adsorption flotation

Role of ammonium sulfate in sulfurization flotation of azurite:Inhibiting the formation of copper sulfide colloid and its mechanism

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International Journal of Mining Science and Technology 2022年第3期32卷 575-584页

作者： Jinpeng Cai Chao Su Yinyu Ma Xingcai Yu Rong Peng Jiangli Li Xiaolin Zhang Jianjun Fang Peilun Shen Dianwen Liu State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Yunnan Key Laboratory of Green Separation and Enrichment of Strategic Metal ResourcesFaculty of Land Resources EngineeringKunming University of Science and TechnologyKunming 650093China Shandong Gold Group Co. LtdJinan 250014China Yunnan Posphate Group Co. LtdKunming 650600China

In this study,the role of(NH_(4))_(2)SO_(4)during the sulfurization of azurite and its response to flotation were *** flotation results showed that adding(NH_(4))_(2)SO_(4)prior to sulfurization decreased the formation of colloid in flotation pulp,and the floatability of the suppressed azurite caused by excess sodium sulfide was *** adding(NH_(4))_(2)SO_(4)prior to sulfurization,the formation of Cu(NH_(3))_(n) ^(2+)intermediate products changed the path of the sulfurization reaction,which slowed the direct impact of HSon the azurite *** nucleation rate was reduced,and the growth of copper sulfide crystal was ***(syn,CuS)with larger crystal grains was formed on the azurite surface,thereby enhancing the mechanical stability of copper sulfide products onto the mineral ***,the generated copper sulfide colloid significantly reduced,ultimately promoting the effective adsorption of xanthate on the azurite surface.

关键词： Azurite Sulfurization flotation ammonium sulfate Colloid Inhibition Crystal growth

Thermodynamics and kinetics of extracting zinc from zinc oxide ore by the ammonium sulfate roasting method

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International Journal of Minerals,Metallurgy and Materials 2015年第5期22卷 467-475页

作者： Yi Sun Xiao-yi Shen Yu-chun Zhai School of Materials and Metallurgy Northeastern University

Thermodynamic analyses and kinetic studies were performed on zinc oxide ore treatment by （NH4）2SO4 roasting technology. The results show that it is theoretically feasible to realize a roasting reaction between the zinc oxide ore and （NH4）2SO4 in a temperature range of 573-723 K. The effects of reaction temperature and particle size on the extraction rate of zinc were also examined. It is found that a surface chemical reaction is the rate-controlling step in roasting kinetics. The calculated activation energy of this process is about 45.57 kJ/mol, and the kinetic model can be expressed as follows： 1 - （1 - α）1/3 = 30.85 exp（-45.57/RT）·t. An extraction ratio of zinc as high as 92% could be achieved under the optimum conditions.

关键词： zinc metallurgy extraction ammonium sulfate ore roasting thermodynamics kinetics

Atmospheric Corrosion of Steel A3 Deposited with ammonium sulfate and in the Presence of Sulfur Dioxide

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Journal of Materials Science & Technology 2003年第5期19卷 453-455页

作者： YeWAN ChuanweiYAN ChunanCAO JunTAN StateKeyLaboratoryforCorrosionandProtection InstituteofMetalResearchChineseAcademyofSciencesShenyang110016China ShenyangNationalLaboratoryforMaterialsScience InstituteofMetalResearchChineseAcademyofSciencesShenyang110016China

A laboratory study of the atmospheric corrosion of carbon steel deposited with (NH4)2SO4 in the presence of SO2 is reported. The different levels of (NH4)2SO4 (0, 15, 30, 45, 60 μg·cm-2) were added on the surface of the samples before the exposure. The corrosion was investigated by a combination of gravimetry, Fourier transform infrared spectroscope and scanning electron microscopy. A detailed knowledge about the corrosion products was acquired, both quantitatively and qualitatively. The results show that the metal loss increased and the increasing tendency of corrosion rates slowed down with the increasing exposure time. The phase constituents of the corrosion products are mainly α-FeO(OH), γ-FeO(OH), and δ-FeO(OH).

关键词： Steel A3 Atmospheric corrosion Deposition ammonium sulfate Sulfur dioxide

Recovery of valuable metals from a low-grade nickel ore using an ammonium sulfate roasting-leaching process

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International Journal of Minerals,Metallurgy and Materials 2012年第5期19卷 377-383页

作者： Xin-wei L iu Ya-li Feng Hao-ran L i Zhi-chao Yang Zhen-lei Cai Civil and Environmental Engineering School University of Science and Technology Beijing 100083 China National Key State Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Science Beijing 100190 China

Metal leaching from a low-grade nickel ore was investigated using an ammonium sulfate roasting-water leaching process. The nickel ore was mixed with ammonium sulfate, followed by roasting and finally leaching with water. During the process the effects of the amotmt of ammonium sulfate, roasting temperature, and roasting time on the leaching recovery of metal elements were analyzed. The optimum technological parameters were determined as follows： ammonium sulfate/ore ratio, 0.8 g/g; roasting temperature, 400℃; and roasting time, 2 h. Under the optimum condition the leaching recoveries ofNi, Cu, Fe, and Mg were 83.48%, 76.24%, 56.43%, and 62.15%, respectively. Furthermore, the dissolution kinetics of Ni and Mg from the nickel ore was studied. The apparent activation energies for the leaching reaction of Ni and Mg were 18.782 and 10.038 ***1-1, which were consistent with the values of diffusion control reactions. Therefore, the results demonstrated that the leaching recoveries of Ni and Mg were controlled by diffusion.

关键词： nickel ore treatment ammonium sulfate roasting leaching kinetics diffusion

Joint enhancement of lead accumulation in Brassica plants by EDTA and ammonium sulfate in sand culture

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Journal of Environmental Sciences 2002年第2期14卷 216-220页

作者： XIONG Zhi\|ting, LU Ping (Department of Environmental Sciences, Wuhan University, Wuhan 430072, China. Department of Environmental Sciences Wuhan University Wuhan 430072

When EDTA was added alone in the Pb\|contaminated sand, the plant biomass and the total Pb amount in plant decreased in both species, Brassica pekinensis and B. juncea var. multiceps, though the shoot Pb amount increased. In contrast, when (NH 4) 2SO 4 was added alone in the Pb\|contaminated sand, little effect was observed on the shoot Pb amount, though the root Pb amount was significantly increased in B. juncea var. multiceps. When amending EDTA and (NH 4) 2SO 4 in combination, however, the shoot Pb amount in both species substantially increased, being, on an average, 2 times and 9 times higher than that in EDTA alone or (NH 4) 2SO 4 alone amended treatment, respectively. The two amendments showed antagonism for plant growth, but synergism for Pb bioaccumulation. B. pekinensis showed its highest level of shoot and total Pb amount in the treatment amended with EDTA and (NH 4) 2SO 4 only a half as much as in the other treatments. It is inferred that the mechanisms responsible for the joint\|enhanced Pb accumulation might be concerned with the acidification of the growth medium, cation exchange reaction and relieving EDTA induced toxicity as results by amending ammonium sulfate.

关键词： lead bioaccumulation EDTA ammonium sulfate Brassica

Thermal decomposition mechanism of ammonium sulfate catalyzed by ferric oxide

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Frontiers of Chemical Science and Engineering 2013年第2期7卷 210-217页

作者： Xingfu SONG Jingcai ZHAO Yunzhao LI Ze SUN Jianguo YU National Engineering Research Center for Integrated Utilization of Salt Lake Resource East China University of Science and Technology Shanghai 200237 China

The decomposition mechanism of ammonium sulfate catalyzed by ferric oxide was investigated in this paper. The decomposition kinetics parameters were determined via a global optimization of the Kissinger iterative method using the non-isothermal thermogravi- metric analysis data. The products and intermediates were synchronously characterized by X-ray diffraction and mass spectrometry. The obtained results indicate that the decomposition process of ammonium sulfate catalyzed by ferric oxide can be divided into four stages of which the activation energies are 123.64, 126.58, 178.77 and 216.99 kJ. mol^-1 respectively. The decomposition mechanisms at the first and the fourth stage both belong to Mample power theorem, the second stage belongs to Avrami-Erofeev equation and the third belongs to contracting sphere （volume） equation. The corresponding pre-exponential factors （A） are calculated simultaneously.

关键词： ammonium sulfate decomposition kinetics,ferric oxide thermogravimetric analysis

Study on Calcination Process of Serpentine Mixed with ammonium sulfate

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Study on Calcination Process of Serpentine Mixed with Ammoni...

Simultaneous preparation of TiO2 and ammonium alum,and microporous SiO2 during the mineral carbonation of titanium-bearing blast furnace slag

2012 China Functional Materials Technology and Industry Forum

作者： Bei Song Yuran Zhang Yonghao Di Rui Dai Shuilin Zheng School of chemical and environmental engineering China University of Mining and Technology

The research involves the calcination of QingHaiQiLian serpentine with ammonium sulfate in order to extract magnesium,and evaluates calcination results through the mass of water leaching residue that comes from the calcination,dissolution and filtration *** calcination parameters of serpentine and ammonium sulfate determined by orthogonal experiments, single-factor experiments,elemental analysis and SEM analysis are:calcination duration of 1h, calcination temperature of 700℃,ammonium sulfate dosage of 90g(or mass ratio of ammonium sulfate to serpentine sample(m1/m2) of 3:2),under which condition a magnesium extraction rate of 62.75%can be achieved.

关键词： Serpentine ammonium sulfate Calcination Extraction Rate

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Chinese Journal of Chemical Engineering 2020年第9期28卷 2256-2266页

作者： Yingjie Xiong Tahani Aldahri Weizao Liu Guanrun Chu Guoquan Zhang Dongmei Luo Hairong Yue Bin Liang Chun Li School of Chemical Engineering Sichuan UniversityChengdu 610065China Department of Chemical and Biochemical Engineering Western UniversityLondonOntarioCanada Department of physics Taibah UniversityMadinahSaudi Arabia

In this study,a route for simultaneous mineralization of CO2 and production of titanium dioxide and ammonium alum,and microporous silicon dioxide from titanium-bearing blast furnace slag(TBBF slag)was proposed,which is comprised of(NH4)2 S04 roasting,acid leaching,ammonium alum crystallization,silicic acid flocculation and Ti *** effects of relevant process parameters were systematically *** re sults showed that under the optimal roasting and leaching conditions about 85%of titanium and 84.6%of aluminum could be extracted while only 30%of silicon entered the leachate.84%of Al^3+was crystallized from the leachate in the form of ammonium aluminum sulfate dodecahydrate with a purity up to 99.5 wt%.About 85%of the soluble silicic acid was flocculated with the aid of secondary alcohol polyoxyethylene ether 9(AEO-9)to yield a microporous SiO2 material(97.4 wt%)from the crystallized mother *** Al-and Si-depleted solution was then hydrolyzed to generate a titanium dioxide(99.1 wt%)with uniform particle size *** was figured out that approximately 146 kg TiO2 could be produced from 1000 kg of TBBF ***,the improved process is a promising method for industrial application.

关键词： CO2 mineralization Titanium-bearing blast furnace slag ammonium sulfate Flocculation Titanium dioxide