scholarly journals End of Life Tires as a Possible Source of Toxic Substances Emission in the Process of Combustion

Resources ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 113 ◽  
Author(s):  
Irina Glushankova ◽  
Aleksandr Ketov ◽  
Marina Krasnovskikh ◽  
Larisa Rudakova ◽  
Iakov Vaisman
Keyword(s):  
End Of Life ◽  
Significant Proportion ◽  
Deep Oxidation ◽  
Sulfur Compounds ◽  
Oxidation Products ◽  
Hydrocyanic Acid ◽  
Toxic Substances ◽  
Resource Potential ◽  
Steel Cord ◽  
Oxidation Of Sulfur Compounds

Several million tons of end of life tires (ELTs) are piled annually as a result of human activities. Various methods have been proposed for the extraction and recycling of the resource potential of ELTs. The chemical composition of ELTs seems to enable their usage as a fuel after mechanical separation of a steel cord. Indeed, in the rubber of ELTs, up to 90 mass% accounts for carbon and hydrogen. Currently, it is by incineration that a significant proportion of ELTs is utilized. However, ELTs contain not only sulfur, which is used for vulcanization, but also nitrogen-containing additives. The behavior of these heteroatoms during oxidation is poorly investigated. It has been shown that the pyrolysis liquid fuel obtained from ELTs contains such sulfur compounds as mercaptans and nitrogen in the form of hydrocyanic acid and cyanogen. Deep oxidation of ELTs results in the oxidation of sulfur compounds to dioxide, but the oxidation products have been found to contain traces of cyanogen. Taking this into account, one should pay attention to the ways of transforming heteroatoms during the process of ELT oxidation and the products of ELT pyrolysis as potential sources of highly toxic gas emissions.

Biological oxidation of sulfur compounds in artificially degraded wood

2019 ◽  
Vol 141 ◽  
pp. 62-70 ◽  
Author(s):  
Magdalena Albelda Berenguer ◽  
Mathilde Monachon ◽  
Clémentine Jacquet ◽  
Pilar Junier ◽  
Céline Rémazeilles ◽  
...  
Keyword(s):  
Sulfur Compounds ◽  
Biological Oxidation ◽  
Oxidation Of Sulfur Compounds

scholarly journals Describing the characteristics and healthcare use of high-cost acute care users at the end of life: a pan-Canadian population-based study

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Danial Qureshi ◽  
Sarina Isenberg ◽  
Peter Tanuseputro ◽  
Rahim Moineddin ◽  
Kieran Quinn ◽  
...  
Keyword(s):  
End Of Life ◽  
Acute Care ◽  
Significant Proportion ◽  
Population Based ◽  
Fiscal Year ◽  
Healthcare Use ◽  
Population Based Study ◽  
Canadian Population ◽  
Alternate Level Of Care ◽  
Care Costs

Abstract Background A minority of individuals use a large portion of health system resources, incurring considerable costs, especially in acute-care hospitals where a significant proportion of deaths occur. We sought to describe and contrast the characteristics, acute-care use and cost in the last year of life among high users and non-high users who died in hospitals across Canada. Methods We conducted a population-based retrospective-cohort study of Canadian adults aged ≥18 who died in hospitals across Canada between fiscal years 2011/12–2014/15. High users were defined as patients within the top 10% of highest cumulative acute-care costs in each fiscal year. Patients were categorized as: persistent high users (high-cost in death year and year prior), non-persistent high users (high-cost in death year only) and non-high users (never high-cost). Discharge abstracts were used to measure characteristics and acute-care use, including number of hospitalizations, admissions to intensive-care-unit (ICU), and alternate-level-of-care (ALC). Results We identified 191,310 decedents, among which 6% were persistent high users, 41% were non-persistent high users, and 46% were non-high users. A larger proportion of high users were male, younger, and had multimorbidity than non-high users. In the last year of life, persistent high users had multiple hospitalizations more often than other groups. Twenty-eight percent of persistent high users had ≥2 ICU admissions, compared to 8% of non-persistent high users and only 1% of non-high users. Eleven percent of persistent high users had ≥2 ALC admissions, compared to only 2% of non-persistent high users and < 1% of non-high users. High users received an in-hospital intervention more often than non-high users (36% vs. 19%). Despite representing only 47% of the cohort, persistent and non-persistent high users accounted for 83% of acute-care costs. Conclusions High users – persistent and non-persistent – are medically complex and use a disproportionate amount of acute-care resources at the end of life. A greater understanding of the characteristics and circumstances that lead to persistently high use of inpatient services may help inform strategies to prevent hospitalizations and off-set current healthcare costs while improving patient outcomes.

scholarly journals Reduction of Iron(III) Ions at Elevated Pressure by Acidophilic Microorganisms

2017 ◽  
Vol 262 ◽  
pp. 88-92 ◽  
Author(s):  
Rui Yong Zhang ◽  
Sabrina Hedrich ◽  
Axel Schippers
Keyword(s):  
High Pressure ◽  
Iron Reduction ◽  
Enrichment Culture ◽  
Elevated Pressure ◽  
Pressure Vessels ◽  
Ore Deposits ◽  
Sulfur Compounds ◽  
Cell Counting ◽  
Iron Cycling ◽  
Oxidation Of Sulfur Compounds

A composed mixed acidophilic, iron-oxidizing culture (FIGB) and a thermo-acidophilic enrichment culture (TK65) were used to evaluate microbial iron(III) reduction coupled to oxidation of reduced inorganic sulfur compounds (RISCs) under high pressure. Experiments were done in batch culture in high pressure vessels at 1 and 100 bar. Microbial abundance and activity were determined by measuring iron(II) concentration, direct cell counting, T-RFLP and quantitative real-time PCR. The data indicate that both cultures are able to reduce soluble iron(III) by oxidation of sulfur compounds under anaerobic conditions. At high pressure (100 bar) these acidophiles were capable of growing and microbial ferric iron reduction was only partially inhibited. These results indicate that acidophiles can be barotolerant and their activities are contributing to sulfur and iron cycling in anaerobic environments including deep ore deposits which is highly relevant for in situ leaching operations.

Mild and Selective Oxidation of Sulfur Compounds in Trifluoroethanol: Diphenyl Disulfide and Methyl Phenyl Sulfoxide

2003 ◽  
pp. 184-189 ◽  
Author(s):  
Kabayadi S. Ravikumar ◽  
Venkitasamy Kesavan ◽  
Benoit Crousse ◽  
Danièle Bonnet-Delpon ◽  
Jean-Pierre Bégué
Keyword(s):  
Selective Oxidation ◽  
Sulfur Compounds ◽  
Diphenyl Disulfide ◽  
Oxidation Of Sulfur Compounds ◽  
Methyl Phenyl

scholarly journals Evidence for a significant proportion of Secondary Organic Aerosol from isoprene above a maritime tropical forest

2011 ◽  
Vol 11 (3) ◽  
pp. 1039-1050 ◽  
Author(s):  
N. H. Robinson ◽  
J. F. Hamilton ◽  
J. D. Allan ◽  
B. Langford ◽  
D. E. Oram ◽  
...  
Keyword(s):  
Secondary Organic Aerosol ◽  
Significant Proportion ◽  
Organic Aerosol ◽  
Oxidation Products ◽  
Emission Region ◽  
Experimental Chamber ◽  
Mass Spectral ◽  
Aerosol Mass ◽  
Isoprene Oxidation ◽  
Highly Correlated

Abstract. Isoprene is the most abundant non-methane biogenic volatile organic compound (BVOC), but the processes governing secondary organic aerosol (SOA) formation from isoprene oxidation are only beginning to become understood and selective quantification of the atmospheric particulate burden remains difficult. Organic aerosol above a tropical rainforest located in Danum Valley, Borneo, Malaysia, a high isoprene emission region, was studied during Summer 2008 using Aerosol Mass Spectrometry and offline detailed characterisation using comprehensive two dimensional gas chromatography. Observations indicate that a substantial fraction (up to 15% by mass) of atmospheric sub-micron organic aerosol was observed as methylfuran (MF) after thermal desorption. This observation was associated with the simultaneous measurements of established gas-phase isoprene oxidation products methylvinylketone (MVK) and methacrolein (MACR). Observations of MF were also made during experimental chamber oxidation of isoprene. Positive matrix factorisation of the AMS organic mass spectral time series produced a robust factor which accounts for an average of 23% (0.18 μg m−3), reaching as much as 53% (0.50 μg m−3) of the total oraganic loading, identified by (and highly correlated with) a strong MF signal. Assuming that this factor is generally representative of isoprene SOA, isoprene derived aerosol plays a significant role in the region. Comparisons with measurements from other studies suggest this type of isoprene SOA plays a role in other isoprene dominated environments, albeit with varying significance.

Gold nanoparticles supported on modified red mud for biphasic oxidation of sulfur compounds: A synergistic effect

2015 ◽  
Vol 162 ◽  
pp. 475-482 ◽  
Author(s):  
Aline A.S. Oliveira ◽  
Demétrio A.S. Costa ◽  
Ivo F. Teixeira ◽  
Flávia C.C. Moura
Keyword(s):  
Gold Nanoparticles ◽  
Synergistic Effect ◽  
Red Mud ◽  
Sulfur Compounds ◽  
Oxidation Of Sulfur Compounds

scholarly journals The Effects of Different Sulfur Compounds on Jet Fuel Oxidation and Deposition

1995 ◽  
Author(s):  
Robert E. Kauffman
Keyword(s):  
Jet Fuel ◽  
Sulfur Compounds ◽  
Oxidation Products ◽  
Jet Fuels ◽  
Acid Base ◽  
Deposition Mechanism ◽  
Fuel Oxidation ◽  
Basic Nitrogen ◽  
Elemental Analyses ◽  
Steel Surfaces

This paper presents research which supports a proposed fuel oxidation/deposition mechanism involving acid: base reactions between “oxidizable” sulfur compounds, “basic” nitrogen compounds, and oxygen containing polymers. The reported research presents experiments which study the effects of different sulfur compounds on the high temperature (160–220°C) oxidation products and deposition tendencies of jet fuel. Surface analyses incorporating elemental analyses and depth profiles of deposits formed on steel surfaces were performed to identify the species involved in the initial stages of deposition by jet fuels. Experiments to study the effects of acid neutralizing compounds on the deposition tendencies of jet fuels are also presented.

Oxidation of inorganic sulfur compounds: Chemical and enzymatic reactions

1999 ◽  
Vol 45 (2) ◽  
pp. 97-105 ◽  
Author(s):  
Isamu Suzuki
Keyword(s):  
Sulfur Oxidation ◽  
Chemical Oxidation ◽  
Sulfur Compounds ◽  
Enzymatic Oxidation ◽  
Enzymatic Reactions ◽  
Oxidation Reactions ◽  
Microbial Oxidation ◽  
Inorganic Sulfur ◽  
Nucleophilic Cleavage ◽  
Oxidation Of Sulfur Compounds

Microbial oxidation of inorganic sulfur compounds is governed by both chemical and enzymatic reactions. It is therefore essential to understand reactions possible in chemistry when we consider enzymatic reactions. Various oxidation states of sulfur atoms in inorganic sulfur compounds and chemical oxidation reactions as well as nucleophilic cleavage of sulfur-sulfur bonds are discussed. The scheme of enzymatic oxidation of sulfur compounds with S2-→> S0→> SO32-→> SO42-as the main oxidation pathway is discussed with thiosulfate and polythionates leading into the main pathway for complete oxidation to sulfate. Enzymatic reactions are related to chemical reactions and the use of inhibitors for S0→> SO32-and SO32-→> SO42-is discussed for analyzing and establishing reaction stoichiometries. The proposed pathway is supported by a variety of evidence in many different microorganisms including some genetic evidence if the oxidation steps include all the systems irrespective of oxidizing agents (O2, Fe3+, cytochromes etc.).Key words: sulfur, oxidation, chemical, enzymatic, reactions.

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