1
|
Pan C, Niu M, Cui R, Li L, You X, Sun X, Ji C, Epstein IR, Gao Q. Mesoscopic Pitting Oscillation-Induced Periodic Anodic Layer Electrodissolution of Au(111). J Phys Chem Lett 2021; 12:12062-12066. [PMID: 34908416 DOI: 10.1021/acs.jpclett.1c03300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The electrodissolution of Au(111) in anaerobic cupric/ammonia/thiosulfate solutions, typical of a non-equilibrium dissipative system, was investigated via in situ electrochemical atomic force microscopy. At a specific initial concentration ratio of aqueous ammonia to cupric ions, the pit number and average pit area increase autocatalytically, while the pit depth increases monotonically during dissolution. A further increase in this initial concentration ratio leads to oscillatory dynamics in the pit number and average pit area while the pit depth fluctuates between one and two atoms. Mechanistic analysis indicates that alternation between formation and dissolution of a sulfur film results in periodic pitting, which produces gold dissolution layer by layer. This work presents a new dissolution mode, i.e., periodic layer dissolution generated by oscillatory pitting processes in addition to a pitting mode with a continually increasing depth, and the use of high initial concentration ratios of ammonia to cupric ion to accelerate the elimination of passivating sulfur film for Au dissolution.
Collapse
Affiliation(s)
- Changwei Pan
- Department of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116, P. R. China
| | - Mingshuang Niu
- Department of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116, P. R. China
| | - Ruijun Cui
- Department of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116, P. R. China
| | - Lianqun Li
- Department of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116, P. R. China
| | - Xinyu You
- Department of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116, P. R. China
| | - Xiao Sun
- Department of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116, P. R. China
| | - Chen Ji
- Department of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116, P. R. China
| | - Irving R Epstein
- Department of Chemistry and Volen Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02454-9110, United States
| | - Qingyu Gao
- Department of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116, P. R. China
| |
Collapse
|
2
|
Spatolisano E, Pellegrini LA, Gelosa S, Broglia F, Bonoldi L, de Angelis AR, Moscotti DG, Nali M. Polythionic Acids in the Wackenroder Reaction. ACS OMEGA 2021; 6:26140-26149. [PMID: 34660974 PMCID: PMC8515606 DOI: 10.1021/acsomega.1c03139] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 09/14/2021] [Indexed: 06/13/2023]
Abstract
Polythionic acids, whose general formula is H2S n O6, with n greater than 2, were discovered in the aqueous solution of SO2 and H2S, known as the Wackenroder liquid. Their reactions with each other and with other reagents are, mostly, difficult to characterize, since such compounds readily decompose and interconvert, especially in solution. Nevertheless, they play an important role in technical applications (e.g., gold leaching, magnesium milling, cooling in metal processing) and in reactions of inorganic chemistry of sulfur. A few years ago, Shell-Paques/Paqell patented the first industrial process for the biological conversion of H2S into a colloidal mixture of sulfur and polythionates. Such hydrophilic sulfur can be used as a fertilizer and soil improver in agriculture in all but alkaline soils. Recently, Eni S.p.A. has developed to bench plant scale a new process, the HydroClaus process for the conversion of H2S into an acidic hydrophilic slurry of sulfur and polythionate ions. Such a slurry can be used as a soil improver where the very alkaline soil pH hinders the cultivation. The aim of this work is to study the laboratory-scale production of polythionates in view of the novel HydroClaus process scale-up at the industrial level. After the literature related to polythionates and their characterization has been revised, the sulfur-based mixture has been synthesized and the polythionate ions concentration has been determined. Also, the effect of the reaction operating conditions has been investigated to assess how they can influence the nature and the distribution of products in solution.
Collapse
Affiliation(s)
- Elvira Spatolisano
- Dipartimento
di Chimica, Materiali e Ingegneria Chimica “G. Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Laura A. Pellegrini
- Dipartimento
di Chimica, Materiali e Ingegneria Chimica “G. Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Simone Gelosa
- Dipartimento
di Chimica, Materiali e Ingegneria Chimica “G. Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milano, Italy
| | - Francesca Broglia
- Dipartimento
di Chimica, Materiali e Ingegneria Chimica “G. Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milano, Italy
| | - Lucia Bonoldi
- Research
and Technological Innovation Department, Eni S.p.A., via F. Maritano 26, 20097 San Donato Milanese, Italy
| | - Alberto Renato de Angelis
- Research
and Technological Innovation Department, Eni S.p.A., via F. Maritano 26, 20097 San Donato Milanese, Italy
| | - Daniele Giulio Moscotti
- Research
and Technological Innovation Department, Eni S.p.A., via F. Maritano 26, 20097 San Donato Milanese, Italy
| | - Micaela Nali
- Research
and Technological Innovation Department, Eni S.p.A., via F. Maritano 26, 20097 San Donato Milanese, Italy
| |
Collapse
|
3
|
Pan C, Lv F, Kégl T, Horváth AK, Gao Q. Kinetics and Mechanism of the Concurrent Reactions of Hexathionate with S(IV) and Thiosulfate in a Slightly Acidic Medium. J Phys Chem A 2019; 123:5418-5427. [PMID: 31180657 DOI: 10.1021/acs.jpca.9b00276] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Reactions of hexathionate with thiosulfate and sulfite have been investigated by high-performance liquid chromatography via monitoring the concentration-time series of tetrathionate, pentathionate, hexathionate, and thiosulfate simultaneously within the pH range of 4.0-5.0. In both reactions, elementary sulfur forms; more significant sulfur precipitation may be observed in the case of the hexathionate-thiosulfate reaction, but slight turbidity in the other system means that elementary sulfur also appears in a detectable amount in the hexathionate-sulfite reaction. Initial rate studies have revealed that the formal kinetic orders of both reactants in both systems are clearly unity but pH-dependence can only be observed in the case of the hexathionate-sulfite reaction. The proposed kinetic model appears to suggest that nucleophilic attack of sulfite and thiosulfate may also occur on the β- or γ-sulfur of the polythionate chain and breakages of the α-β, β-γ, and γ-γ' bonds are all conceivable possibilities to drive the reactions. Consequently, the generally accepted sulfur-chain elongating effect of thiosulfate on longer polythionates is also proven to be accompanied by sulfur-chain shortening pathways, eventually leading to the formation of elementary sulfur.
Collapse
Affiliation(s)
- Changwei Pan
- College of Chemical Engineering , China University of Mining and Technology , Xuzhou 221116 , People's Republic of China
| | - Fengpeng Lv
- College of Chemical Engineering , China University of Mining and Technology , Xuzhou 221116 , People's Republic of China
| | | | | | - Qingyu Gao
- College of Chemical Engineering , China University of Mining and Technology , Xuzhou 221116 , People's Republic of China
| |
Collapse
|
4
|
Ji C, Yan X, Pan C, Lv F, Gao Q. The Key Heterolysis Selectivity of Divalent Sulfur–Sulfur Bonds for a Unified Mechanistic Scheme in the Thiosulfatolysis and Sulfitolysis of the Pentathionate Ion. Eur J Inorg Chem 2016. [DOI: 10.1002/ejic.201600991] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Chen Ji
- College of Chemical Engineering China University of Mining and Technology 221116 Xuzhou People's Republic of China
| | - Xiangdong Yan
- College of Chemical Engineering China University of Mining and Technology 221116 Xuzhou People's Republic of China
| | - Changwei Pan
- College of Chemical Engineering China University of Mining and Technology 221116 Xuzhou People's Republic of China
| | - Fengpeng Lv
- College of Chemical Engineering China University of Mining and Technology 221116 Xuzhou People's Republic of China
| | - Qingyu Gao
- College of Chemical Engineering China University of Mining and Technology 221116 Xuzhou People's Republic of China
| |
Collapse
|
5
|
Li G, Xia Y, Zhao Y, Li P, Zhang F, Qu P. Solid–Liquid Reaction Synthesis of High-Purity Potassium Hexathionate and Its Antibacterial Properties. Aust J Chem 2016. [DOI: 10.1071/ch15329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Hexathionate, an intermediate in the oxidation process of inorganic sulfur compounds, plays important roles in different fields of chemistry, chemical technology, and biology. To achieve innovative results in different fields related to polythionates, the use of hexathionate is crucial, however, it is not yet commercially available. Herein, we report a simple and convenient method to prepare high-purity potassium hexathionate. Hexathionic acid was easily synthesised through a solid–liquid reaction between sodium thiosulfate (solid) and disulfur dichloride. The potassium salt crude product was obtained by neutralising hexathionate acid with potassium hydroxide, and was purified successively using 0.1 M sulfuric acid and 0.5 M hydrochloric acid. A high product purity of 99.8 % (titrimetric analysis, 98.81 %) was obtained. The antibacterial activities of potassium hexathionate against Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Pseudomonas aeruginosa (P. aeruginosa) were determined by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) analyses and the cup diffusion method. Potassium hexathionate displayed more effective antibacterial activities against P. aeruginosa than S. aureus. The MICs against P. aeruginosa and S. aureus were 1.95 and 125 µg mL–1, respectively. The corresponding MBC value against P. aeruginosa was 1000 µg mL–1. Furthermore, the duration of the antimicrobial activity, determined by the cup diffusion, shows the potential of potassium hexathionate as a sustained antibacterial candidate. However, there is no bactericidal activity against S. aureus in the concentration range tested.
Collapse
|
6
|
Ji C, Yan X, Horváth AK, Pan C, Zhao Y, Gao Q. Comprehensive simultaneous kinetic study of sulfitolysis and thiosulfatolysis of tetrathionate ion: unravelling the unique pH dependence of thiosulfatolysis. J Phys Chem A 2015; 119:1238-45. [PMID: 25651337 DOI: 10.1021/jp5108119] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The kinetics of the reactions of tetrathionate with S(IV) species and with thiosulfate in slightly acidic and neutral media were studied concurrently at 25.0 ± 0.1 °C by simultaneous high-performance liquid chromatography monitoring of the concentrations of polythionates (including trithionate, tetrathionate, and pentathionate), thiosulfate, and sulfite. The tetrathionate-sulfite and tetrathionate-thiosulfate reactions were found to be first-order with respect to both reactants. The tetrathionate-sulfite reaction was found to be pH-dependent under the conditions studied. In contrast, the tetrathionate-thiosulfate reaction was experimentally demonstrated to be pH-independent at neutral medium, where the pKa2 value of sulfurous acid plays a key role, whereas under slightly acidic conditions, between pH 4 and 5 the consumption of tetrathionate during the course of reaction was found to become pH-dependent. We show that the pH dependencies in both systems can be readily explained by the reactivity difference between sulfite and bisulfite toward the β-sulfur of the tetrathionate. A simple two-step kinetic model incorporating the protonation equilibrium of sulfite is proposed on the basis of the simultaneous evaluation of the kinetic curves of the two systems, which allowed us to determine reliable rate coefficients for both the forward and backward reactions. Furthermore, the powerful ability of simultaneously evaluating the two chemical systems to yield reliable rate coefficients of the kinetic model is demonstrated.
Collapse
Affiliation(s)
- Chen Ji
- School of Chemical Engineering, China University of Mining and Technology , Xuzhou 221116, People's Republic of China
| | | | | | | | | | | |
Collapse
|
7
|
Li G, Zhao Y, Li P, Zhang F, Qu P, Li B, Gao Q, Wang S. Antibacterial activities of polythionates enhanced by carbonates. MEDCHEMCOMM 2015. [DOI: 10.1039/c5md00275c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The antibacterial activity of polythionates enhanced by carbonates is related to the formation of active sulfur from the decomposition of polythionates.
Collapse
Affiliation(s)
- Guofang Li
- College of Chemical Engineering
- China University of Mining and Technology
- Xuzhou 221008
- China
- School of Chemical Engineering
| | - Yanbao Zhao
- Key Laboratory for Special Functional Materials
- Henan University
- Kaifeng 475004
- China
| | - Ping Li
- Key Laboratory for Special Functional Materials
- Henan University
- Kaifeng 475004
- China
| | - Fuqiang Zhang
- School of Chemical Engineering
- Shangqiu Normal University
- Shangqiu 476000
- China
| | - Peng Qu
- School of Chemical Engineering
- Shangqiu Normal University
- Shangqiu 476000
- China
| | - Binjie Li
- Key Laboratory for Special Functional Materials
- Henan University
- Kaifeng 475004
- China
| | - Qingyu Gao
- College of Chemical Engineering
- China University of Mining and Technology
- Xuzhou 221008
- China
| | - Shaorong Wang
- College of Chemical Engineering
- China University of Mining and Technology
- Xuzhou 221008
- China
| |
Collapse
|
8
|
Xu L, Csekő G, Petz A, Horváth AK. Kinetics and Mechanism of the Oxidation of Pentathionate Ion by Chlorine Dioxide in a Slightly Acidic Medium. J Phys Chem A 2014; 118:1293-9. [DOI: 10.1021/jp412333e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Li Xu
- Department of Inorganic
Chemistry, University of Pécs, Ifjúság útja
6, H-7624 Hungary
- János Szentágothai
Research Center, Pécs, Ifjúság útja 20, H-7624 Hungary
| | - György Csekő
- Department of Inorganic
Chemistry, University of Pécs, Ifjúság útja
6, H-7624 Hungary
- János Szentágothai
Research Center, Pécs, Ifjúság útja 20, H-7624 Hungary
| | - Andrea Petz
- Department of Inorganic
Chemistry, University of Pécs, Ifjúság útja
6, H-7624 Hungary
- János Szentágothai
Research Center, Pécs, Ifjúság útja 20, H-7624 Hungary
| | - Attila K. Horváth
- Department of Inorganic
Chemistry, University of Pécs, Ifjúság útja
6, H-7624 Hungary
- János Szentágothai
Research Center, Pécs, Ifjúság útja 20, H-7624 Hungary
| |
Collapse
|
9
|
Csekő G, Ren L, Liu Y, Gao Q, Horváth AK. A new system for studying spatial front instabilities: the supercatalytic chlorite-trithionate reaction. J Phys Chem A 2014; 118:815-21. [PMID: 24450602 DOI: 10.1021/jp410470r] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We show that the chlorite-trithionate reaction is "supercatalytic"; i.e., the formal kinetic order of the autocatalyst H(+) is 2. A simple model is proposed and discussed to describe the unusual concentration dependencies of one-dimensional front propagation found experimentally. It is also demonstrated that at relatively wide concentration ranges the linear two-dimensional front initiated loses its stability, giving rise to an appearance of cellular structures in a convection-free system. Compared to the chlorite-tetrathionate reaction, however, this system is much more stable at alkaline conditions, even for hours; therefore, no side reactions can be taken into consideration to check whether they may have any side effects on the evolution of spatiotemporal structures.
Collapse
Affiliation(s)
- György Csekő
- Department of Inorganic Chemistry, University of Pécs , Ifjúság útja 6., H-7624 Pécs, Hungary
| | | | | | | | | |
Collapse
|
10
|
Näther C, Wöhlert S, Boeckmann J, Wriedt M, Jeß I. A Rational Route to Coordination Polymers with Condensed Networks and Cooperative Magnetic Properties. Z Anorg Allg Chem 2013. [DOI: 10.1002/zaac.201300274] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
11
|
Pan C, Liu Y, Horváth AK, Wang Z, Hu Y, Ji C, Zhao Y, Gao Q. Kinetics and Mechanism of the Alkaline Decomposition of Hexathionate Ion. J Phys Chem A 2013; 117:2924-31. [DOI: 10.1021/jp400339u] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Changwei Pan
- College of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116,
People’s Republic of China
| | - Yang Liu
- College of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116,
People’s Republic of China
| | - Attila K. Horváth
- Department of Inorganic Chemistry, University of Pécs, Ifjúság útja
6., H-7624 Pécs, Hungary
| | - Zhen Wang
- College of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116,
People’s Republic of China
| | - Ying Hu
- College of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116,
People’s Republic of China
| | - Chen Ji
- College of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116,
People’s Republic of China
| | - Yuemin Zhao
- College of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116,
People’s Republic of China
| | - Qingyu Gao
- College of Chemical Engineering, China University of Mining and Technology, Xuzhou 221116,
People’s Republic of China
| |
Collapse
|
12
|
Xu L, Csekö G, Kégl T, Horváth AK. General Pathway of Sulfur-Chain Breakage of Polythionates by Iodine Confirmed by the Kinetics and Mechanism of the Pentathionate–Iodine Reaction. Inorg Chem 2012; 51:7837-43. [DOI: 10.1021/ic300895c] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Li Xu
- Department of Inorganic Chemistry, University of Pécs, Ifjúság
útja 6, H-7624 Hungary
- János Szentágothai Research Center, Pécs, Ifjúság útja
34, H-7624 Hungary
| | - György Csekö
- Department of Inorganic Chemistry, University of Pécs, Ifjúság
útja 6, H-7624 Hungary
- János Szentágothai Research Center, Pécs, Ifjúság útja
34, H-7624 Hungary
| | - Tamás Kégl
- Department of Inorganic Chemistry, University of Pécs, Ifjúság
útja 6, H-7624 Hungary
- János Szentágothai Research Center, Pécs, Ifjúság útja
34, H-7624 Hungary
| | - Attila K. Horváth
- Department of Inorganic Chemistry, University of Pécs, Ifjúság
útja 6, H-7624 Hungary
- János Szentágothai Research Center, Pécs, Ifjúság útja
34, H-7624 Hungary
| |
Collapse
|