Volatile organic silicon compounds: the most undesirable contaminants in biogases

2008 ◽  
Vol 58 (9) ◽  
pp. 1775-1781 ◽  
Author(s):  
Aurélie Ohannessian ◽  
Valérie Desjardin ◽  
Vincent Chatain ◽  
Patrick Germain
Keyword(s):  
Wastewater Treatment Plants ◽  
Landfill Gas ◽  
Preliminary Test ◽  
Industrial Applications ◽  
Combustion Chambers ◽  
Silicon Compounds ◽  
Organic Silicon ◽  
Silicate Formation ◽  
Wide Range ◽  
Volatile Organic

Recently a lot of attention has been focused on volatile organic silicon compounds (VOSiC) present in biogases. They induce costly problems due to silicate formation during biogas combustion in valorisation engine. The cost of converting landfill gas and digester gas into electricity is adversely affected by this undesirable presence. VOSiC in biogases spark off formation of silicate deposits in combustion chambers. They engender abrasion of the inner surfaces leading to serious damage, which causes frequent service interruptions, thus reducing the economic benefit of biogases. It is already known that these VOSiC originate from polydimethylsiloxanes (PDMS) hydrolysis. PDMS (silicones) are used in a wide range of consumer and industrial applications. PDMS are released into the environment through landfills and wastewater treatment plants. There is a lack of knowledge concerning PDMS biodegradation during waste storage. Consequently, understanding PDMS behaviour in landfill cells and in sludge digester is particularly important. In this article, we focused on microbial degradation of PDMS through laboratory experiments. Preliminary test concerning anaerobic biodegradation of various PDMS have been investigated. Results demonstrate that the biotic step has an obvious influence on PDMS biodegradation.

scholarly journals Volatile Organic Silicon Compounds in Biogases: Development of Sampling and Analytical Methods for Total Silicon Quantification by ICP-OES

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Claire Chottier ◽  
Vincent Chatain ◽  
Jennifer Julien ◽  
Nathalie Dumont ◽  
David Lebouil ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Power Plants ◽  
Optical Emission ◽  
Gas Chromatography Mass Spectrometry ◽  
Emission Spectrometry ◽  
Icp Oes ◽  
Silicon Compounds ◽  
Organic Silicon ◽  
Inductively Coupled ◽  
Volatile Organic

Current waste management policies favor biogases (digester gases (DGs) and landfill gases (LFGs)) valorization as it becomes a way for energy politics. However, volatile organic silicon compounds (VOSiCs) contained into DGs/LFGs severely damage combustion engines and endanger the conversion into electricity by power plants, resulting in a high purification level requirement. Assessing treatment efficiency is still difficult. No consensus has been reached to provide a standardized sampling and quantification of VOSiCs into gases because of their diversity, their physicochemical properties, and the omnipresence of silicon in analytical chains. Usually, samplings are done by adsorption or absorption and quantification made by gas chromatography-mass spectrometry (GC-MS) or inductively coupled plasma-optical emission spectrometry (ICP-OES). In this objective, this paper presents and discusses the optimization of a patented method consisting in VOSiCs sampling by absorption of 100% ethanol and quantification of total Si by ICP-OES.

Microaerobic conditions in anaerobic sludge promote changes in bacterial composition favouring biodegradation of polymeric siloxanes.

2021 ◽  
Author(s):  
Andrés Ortíz-Ardila ◽  
Beatriz Díez ◽  
Crispín Celis ◽  
Pavel Jenicek ◽  
Rodrigo A Labatut
Keyword(s):  
Energy Conversion ◽  
Anaerobic Sludge ◽  
Bacterial Composition ◽  
Ecological Dynamics ◽  
Silicon Compounds ◽  
Organic Silicon ◽  
Volatile Organic ◽  
Energy Conversion Systems ◽  
Microaerobic Conditions

Volatile organic silicon compounds (VOSiC) are harmful pollutants to the biota and ecological dynamics as well as biogas-based energy conversion systems. However, there is a lack of understanding regarding the...

Substituent Effects on the Thermal Decomposition of Phosphate Esters on Ferrous Surfaces

2019 ◽  
Author(s):  
James Ewen ◽  
Carlos Ayestaran Latorre ◽  
Arash Khajeh ◽  
Joshua Moore ◽  
Joseph Remias ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Film Formation ◽  
Substituent Effects ◽  
Vapour Phase ◽  
Industrial Applications ◽  
Phosphate Esters ◽  
Antiwear Additives ◽  
Formation Mechanisms ◽  
Phosphate Ester ◽  
Wide Range

<p>Phosphate esters have a wide range of industrial applications, for example in tribology where they are used as vapour phase lubricants and antiwear additives. To rationally design phosphate esters with improved tribological performance, an atomic-level understanding of their film formation mechanisms is required. One important aspect is the thermal decomposition of phosphate esters on steel surfaces, since this initiates film formation. In this study, ReaxFF molecular dynamics simulations are used to study the thermal decomposition of phosphate esters with different substituents on several ferrous surfaces. On Fe<sub>3</sub>O<sub>4</sub>(001) and α-Fe(110), chemisorption interactions between the phosphate esters and the surfaces occur even at room temperature, and the number of molecule-surface bonds increases as the temperature is increased from 300 to 1000 K. Conversely, on hydroxylated, amorphous Fe<sub>3</sub>O<sub>4</sub>, most of the molecules are physisorbed, even at high temperature. Thermal decomposition rates were much higher on Fe<sub>3</sub>O<sub>4</sub>(001) and particularly α-Fe(110) compared to hydroxylated, amorphous Fe<sub>3</sub>O<sub>4</sub>. This suggests that water passivates ferrous surfaces and inhibits phosphate ester chemisorption, decomposition, and ultimately film formation. On Fe<sub>3</sub>O<sub>4</sub>(001), thermal decomposition proceeds mainly through C-O cleavage (to form surface alkyl and aryl groups) and C-H cleavage (to form surface hydroxyls). The onset temperature for C-O cleavage on Fe<sub>3</sub>O<sub>4</sub>(001) increases in the order: tertiary alkyl < secondary alkyl < primary linear alkyl ≈ primary branched alkyl < aryl. This order is in agreement with experimental observations for the thermal stability of antiwear additives with similar substituents. The results highlight surface and substituent effects on the thermal decomposition of phosphate esters which should be helpful for the design of new molecules with improved performance.</p>

PLATINUM

Alloy Digest ◽  
1970 ◽  
Vol 19 (11) ◽  
Keyword(s):  
Corrosion Resistance ◽  
High Temperature ◽  
Heat Treating ◽  
Industrial Applications ◽  
High Melting ◽  
High Melting Point ◽  
White Metal ◽  
Temperature Performance ◽  
Wide Range ◽  
Corrosion And Oxidation

Abstract PLATINUM is a soft, ductile, white metal which can be readily worked either hot or cold. It has a wide range of industrial applications because of its excellent corrosion and oxidation resistance and its high melting point. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Pt-1. Producer or source: Matthey Bishop Inc..

Nanofiltration of endocrine disrupting compounds

2003 ◽  
Vol 3 (5-6) ◽  
pp. 321-327 ◽  
Author(s):  
M. Gallenkemper ◽  
T. Wintgens ◽  
T. Melin
Keyword(s):  
Wastewater Treatment ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Endocrine Disrupting Compounds ◽  
Municipal Wastewater Treatment ◽  
Water And Wastewater Treatment ◽  
Wide Range ◽  
Endocrine Disrupting ◽  
Municipal Wastewater Treatment Plants ◽  
Set Up

Endocrine disrupting compounds can affect the hormone system in organisms. A wide range of endocrine disrupters were found in sewage and effluents of municipal wastewater treatment plants. Toxicological evaluations indicate that conventional wastewater treatment plants are not able to remove these substances sufficiently before disposing effluent into the environment. Membrane technology, which is proving to be an effective barrier to these substances, is the subject of this research. Nanofiltration provides high quality permeates in water and wastewater treatment. Eleven different nanofiltration membranes were tested in the laboratory set-up. The observed retention for nonylphenol (NP) and bisphenol A (BPA) ranged between 70% and 100%. The contact angle is an indicator for the hydrophobicity of a membrane, whose influence on the permeability and retention of NP was evident. The retention of BPA was found to be inversely proportional to the membrane permeability.

scholarly journals The aspects of microbial biomass use in the utilization of selected waste from the agro-food industry

2020 ◽  
Vol 15 (1) ◽  
pp. 787-796 ◽  
Author(s):  
Marek Kieliszek ◽  
Kamil Piwowarek ◽  
Anna M. Kot ◽  
Katarzyna Pobiega
Keyword(s):  
Food Industry ◽  
Industrial Applications ◽  
Waste Products ◽  
Yeast Biomass ◽  
Wide Range ◽  
Innovative Solutions ◽  
Biomass Management ◽  
Effective Use ◽  
Modern Technologies ◽  
Biomass Of Microorganisms

AbstractCellular biomass of microorganisms can be effectively used in the treatment of waste from various branches of the agro-food industry. Urbanization processes and economic development, which have been intensifying in recent decades, lead to the degradation of the natural environment. In the first half of the 20th century, problems related to waste management were not as serious and challenging as they are today. The present situation forces the use of modern technologies and the creation of innovative solutions for environmental protection. Waste of industrial origin are difficult to recycle and require a high financial outlay, while the organic waste of animal and plant origins, such as potato wastewater, whey, lignin, and cellulose, is dominant. In this article, we describe the possibilities of using microorganisms for the utilization of various waste products. A solution to reduce the costs of waste disposal is the use of yeast biomass. Management of waste products using yeast biomass has made it possible to generate new metabolites, such as β-glucans, vitamins, carotenoids, and enzymes, which have a wide range of industrial applications. Exploration and discovery of new areas of applications of yeast, fungal, and bacteria cells can lead to an increase in their effective use in many fields of biotechnology.

scholarly journals Jojoba Oil: An Updated Comprehensive Review on Chemistry, Pharmaceutical Uses, and Toxicity

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1711
Author(s):  
Heba A. Gad ◽  
Autumn Roberts ◽  
Samirah H. Hamzi ◽  
Haidy A. Gad ◽  
Ilham Touiss ◽  
...  
Keyword(s):  
Industrial Applications ◽  
Literature Survey ◽  
Jojoba Oil ◽  
Pharmacological Activities ◽  
Wide Range ◽  
Liver Functions ◽  
History Of ◽  
History Of Use ◽  
Pharmaceutical Uses ◽  
Obesity And Cancer

Jojoba is a widely used medicinal plant that is cultivated worldwide. Its seeds and oil have a long history of use in folklore to treat various ailments, such as skin and scalp disorders, superficial wounds, sore throat, obesity, and cancer; for improvement of liver functions, enhancement of immunity, and promotion of hair growth. Extensive studies on Jojoba oil showed a wide range of pharmacological applications, including antioxidant, anti-acne and antipsoriasis, anti-inflammatory, antifungal, antipyretic, analgesic, antimicrobial, and anti-hyperglycemia activities. In addition, Jojoba oil is widely used in the pharmaceutical industry, especially in cosmetics for topical, transdermal, and parenteral preparations. Jojoba oil also holds value in the industry as an anti-rodent, insecticides, lubricant, surfactant, and a source for the production of bioenergy. Jojoba oil is considered among the top-ranked oils due to its wax, which constitutes about 98% (mainly wax esters, few free fatty acids, alcohols, and hydrocarbons). In addition, sterols and vitamins with few triglyceride esters, flavonoids, phenolic and cyanogenic compounds are also present. The present review represents an updated literature survey about the chemical composition of jojoba oil, its physical properties, pharmacological activities, pharmaceutical and industrial applications, and toxicity.

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