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The European Market For Organic & Fairtrade Products
Advection is the transport of dissolved solute mass present in groundwater due to the bulk flow (movement) of that groundwater. Advection alone (with no dispersion or reactive processes occurring) would cause a non-reactive solute to advect (move) at the mean groundwater pore velocity. All solutes undergo advection, however, reactive solutes are subject to influences by other processes detailed below. Molecular diffusion is the movement of solute ions in the direction of the con- centration gradient from high towards low concentrations. It effects all solutes. Mechanical dispersion causes spreading of solute and hence dilution of concentrations, it arises from: the tortuosity of...
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Global Chemicals Outlook - Trends and Indicators
Sorption is a process by which chemicals or organisms become attached to soils and/or the geologic rock material (aquifer solids) and removed from the water. Often the sorption process is reversible and solutes desorb and hence dissolved-solute plumes are retarded, rather than solutes being permanently retained by the solids. Cation exchange is the interchange between cations in solution and cations on the surfaces of clay particles or organic colloids. Filtration is a process that affects particulate contaminants (e.g. organig/ inorganic colloids or microbes) rather than dissolved solutes. Particles larger than pore throats diameters or fracture apertures are prevented from moving...
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HANDBOOK ON CHEMICAL WEAPONS CONVENTION FOR INDIAN CHEMICAL INDUSTRY AND CHEMICAL TRADERS
Chemical reactions (abiotic reactions) are “classical” chemical reactions that are not mediated by bacteria. They may include reaction processes such as precipitation, hydrolysis, complexation, elimination, substitution etc. that transform chemicals to other chemicals and potentially alter their phase/state (solid, liquid, gas, dissolved). Precipitation is the removal of ions from solution by the formation of insoluble compounds, i.e. a solid-phase precipitate. Hydrolysis is a process of chemical reaction by the addition of water. Complexation is the reaction process by which compounds are formed in which molecules or ions form coordinate bonds to a metal atom or ion. Biodegradation (biotic reactions) is...
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Chemicals: Health relevance, transport and attenuation
Reactions and transformations of chemicals. Many chemicals undergo reaction or transformation in the subsurface environment. In contrast to retardation contaminants may be removed, rather than simply slowed down. Reactions of harmful chemicals to yield benign products prior to arrival at a receptor are the ideal, e.g. many toxic hydrocarbons have potential to biodegrade to simple organic acids (of low health concern and themselves potentially degradable), carbon dioxide (bicarbonate) and water. Transformation often causes a deactivation (lowering) of toxicity. Reactions and/or transformations incorporate processes such as chemical precipitation, complexation, hydrolysis, biodegradation (biotic reactions) and chemical reactions (abiotic reactions). ...
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Organic Chemicals Sector Guidance for the Large Volume
Chemical precipitation and complexation are primarily important for the inorganic species. The formation of coordination complexes is typical behaviour of transition metals, which provide the cation or central atom. Ligands include common inorganic anions such as Cl - , F- , Br - , SO4 2- , PO4 3- and CO3 2- as well as organic molecules such as amino acids. Such complexation may facilitate the transport of metals. Biodegradation is a reaction process mediated by microbial activity (a biotic reaction). Naturally present bacteria may transform the organic molecule to a simpler product, e.g. another organic molecule or even CO2. Biodegradation has wide applicability to...
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ORGANIC CHEMICALS
The presence of substances in groundwater may be affected by naturally occurring processes as well as by actions directly associated with human activities. Naturally occurring processes such as decomposition of organic material in soils or leaching of mineral deposits can result in increased concentrations of several substances. Those of health concern include arsenic, fluoride, selenium, uranium, nitrate, metals, and radionuclides such as radon. Problems of aesthetic quality and acceptance may be caused by iron, manganese, sulphate, chloride and organic matter. ...
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Remediation of Organic Chemicals in the Vadose Zone
The list of pharmaceutical products in the Pharmaceutical Appendix (Appendix) to the Harmonized Tariff Schedule of the United States (HTS) has grown substantially since 1995. As a result of the first update, 496 items were added to the Appendix. The second update introduced an additional 642 items. The third update added 1,298 items. The current update includes 381 drugs identified by their international nonproprietary names (INNs), 17 prefixes and suffixes to identify derivatives of the INNs, and 354 chemical intermediates. When the current update is completed, the Appendix will include more than 10,000 products. The USTR compiled this list...
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The bioliq® bioslurry gasification process for the production of biosynfuels, organic chemicals, and energy
Pharmaceutical products covered in the Pharmaceutical Zero-for-Zero Initiative can be imported either as bulk active ingredients or in dosage forms that can be packaged for retail sale. Products in dosage form are generally classified under chapter 30 of the HTS, where most of the subheadings are duty-free. Many of the bulk pharmaceutical active ingredients and chemical intermediates are classified under HTS subheadings that also contain non-pharmaceutical products and have rates of duty ranging from 0 to 6.5 percent ad valorem. In order for pharmaceutical products classified under these HTS subheadings to be imported free of duty, they must...
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PROTOCOL FOR EQUIPMENT VERIFICATION TESTING FOR REMOVAL OF SYNTHETIC ORGANIC CHEMICAL CONTAMINANTS
The Appendix consists of three tables. The first table lists the INNs of pharmaceutical active ingredients that are eligible for duty-free treatment. The second table consists of chemical prefixes and suffixes that may be combined with the INNs to specify pharmaceutical derivatives that are also included in the agreement. The third table specifies the chemical intermediates for which duties have been eliminated. U.S. imports of products included in the Pharmaceutical Appendix totaled over $85 billion in 2009; U.S. exports of these products exceeded $41 billion. 1 The pharmaceutical industry has estimated the effect on U.S. imports for only about 12 percent...
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PROTOCOL FOR EQUIPMENT VERIFICATION TESTING OF VOLATILE ORGANIC CHEMICAL REMOVAL
During the Uruguay Round trade negotiations, the United States and several of its major trading partners agreed to eliminate tariffs on pharmaceutical products, certain derivatives, and certain chemical intermediates used in the production of pharmaceuticals. 1 This agreement is known as the Pharmaceutical Zero-for-Zero Initiative (Initiative or Pharmaceutical Agreement). Effective January 1, 1995, the Pharmaceutical Agreement eliminated tariffs in signatory countries on approximately 7,000 pharmaceutical products and chemical intermediates for all World Trade Organization members on a non-discriminatory basis. In the Uruguay Round Agreements Act (URAA), Congress authorized the President to grant duty-free treatment to new pharmaceutical products and chemical intermediates...
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Reduction of Volatile Organic Compound Emissions from Automobile Refinishing
Petroleum contaminant decomposition and in-situ destruction may be accomplished using chemical oxidation technologies. In contrast to other remedial technologies, contaminant reduction can be seen in short time frames (e.g., weeks or months). As discussed in this chapter, a variety of chemical oxidants and application techniques can be used to bring oxidizing materials into contact with subsurface contaminants to remediate the contamination. With sufficient contact time with the organic contaminants, chemical oxidants may be capable of converting the petroleum hydrocarbon mass to carbon dioxide and water and ultimately irreversibly reduce concentrations of petroleum hydrocarbons in soil and groundwater. While many of the chemical oxidants have been...
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National Volatile Organic Compound Emission Standards for Architectural Coatings -- Background for Promulgated Standards
Chemical oxidation technologies are predominantly used to address contaminants in the source area saturated zone and capillary fringe. Cost concerns can preclude the use of chemical oxidation technologies to address large and dilute petroleum contaminant plumes. More frequently, chemical oxidation technologies are employed to treat smaller source areas where the petroleum mass is more concentrated. However, where excessive petroleum contaminant mass exists in the source area and where there is a significant thickness of mobile non-aqueous phase liquids (NAPLs), other remedial technologies (e.g., free product recovery) may need to precede chemical oxidation for the remediation to be safe and cost- effective. ...
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National Volatile Organic Compound Emission Standards For Consumer Products -- Background for Promulgated Standards
Concurrent treatment of source area saturated and unsaturated zones usually requires the integration of chemical oxidation with other remedial technologies that target unsaturated zone contamination (e.g., soil vapor extraction). Frequently, soil vapor extraction, which is used to treat the unsaturated zone, is included as a component of chemical oxidation remedial solutions even if there is no specific need to treat unsaturated soils in the source area. Use of soil vapor extraction in conjunction with chemical oxidation can help alleviate safety issues associated with controlling and recovering off-gas containing volatile organic carbons (VOCs), oxygen, oxidants and other reaction byproducts that can be generated by various chemical oxidants....
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PREDICTION OF CHEMICAL REACTIVITY PARAMETERS AND PHYSICAL PROPERTIES OF ORGANIC COMPOUNDS FROM MOLECULAR STRUCTURE USING SPARC
Soil reactivity with chemical oxidants is also important when considering the costs of the use of chemical oxidation. Excessive loss of a chemical oxidant that is reacting with organics in soil, instead of reacting with the contaminants, may preclude the use of the technology as an economically viable approach to site remediation. Different chemical oxidation technologies are most appropriate for particular hydrogeologic conditions. For example, Fenton’s Reagant may not be ideal for groundwater with high concentrations of carbonate. The carbonate ion preferentially scavenges the hydroxyl radicals created by Fenton’s Reagant reactions before they have a chance to react with the petroleum contaminants. By contrast, the presence...
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Volatile Organic Compound Emissions from Automobile Refinishing -- Background Information for Promulgated Standards
Remedial strategies for petroleum UST sites that include a combination of active source zone treatment with enhanced natural attenuation outside the contaminant plume core may consider chemical oxidation technologies. Many chemical oxidation techniques also provide residual dissolved oxygen that is used by aerobic microorganisms to biodegrade contaminants. In addition, these technologies may also oxidize reduced electron acceptors (e.g., nitrogen to nitrate, sulfides to sulfate), which are then used by anaerobic microorganisms to biodegrade contaminants. For more information on enhanced aerobic remediation technologies, see How to Evaluate Alternative Cleanup Technologies for Underground Storage Tank Sites: A Guide for Corrective Action Plan Reviewers” (EPA-510-B-95-007, 1995). For specific information...
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Small Scale Laboratory: Organic Chemistry at University Level
Das Rohmaterial wird zunächst in Spaltöfen unter Zugabe von Dampf und unter Zufuhr von Energie in niedrigere Kohlenwasserstoffe gespalten. In den nachfolgenden Trennkolonnen werden unter anderem die Produkte Ethylen und Propylen separat abgetrennt. Weitere se- parat abgetrennte Ströme sind das Pyrolysebenzin, die C4 Fraktion (zur Weiterverarbeitung siehe Abschnitt 1,3 – Butadien), Wasserstoff und Ethan. Relevante Emissionen entstehen aus den Spaltöfen durch die Energiebereitstellung für die Spaltung der höheren organischen Verbindungen. In diesem Zusammenhang zu erwähnen sind NOx, CO, CO2, SO2 und Staub. Als Brennstoff wird in den Spaltöfen Raffineriegas ver- wendet. Abwasser entsteht bei der Entfernung der sauren Bestandteile aus...
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BAT FOR LARGE VOLUME ORGANIC CHEMICALS AND PRODUCTION IN AUSTRIA
Die Produktion von Acetylen kann auf zwei grundsätzlich verschiedene Arten durchgeführt werden. Einerseits kann Acetylen durch nichtkatalytische Pyrolyse von Kohlenwasserstoffen erzeugt werden. Dabei kann ein weiter Bereich an Kohlenwasserstoffen als Rohmaterial ein- gesetzt werden. Andererseits besteht die Möglichkeit der Verwendung von Kalziumkarbid und Wasser als Rohmaterialien. In der vorliegenden Studie wird nur die zweite Möglichkeit genauer betrachtet, weil in Österreich sechs Anlagen existieren, die Acetylen auf Basis von Kalziumkarbid herstellen. Die Gesamtjahresproduktion dieser sechs Anlagen liegt allerdings unter 2000 Tonnen. Bei der Verwendung von Kalziumkarbid als Ausgangsstoff entsteht in einer exothermen Re- aktion aus Kalziumkarbid und Wasser Acetylen und das Nebenprodukt...
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ORGANIC CONTAMINANTS IN SEWAGE SLUDGE FOR AGRICULTURAL USE
Es werden zwei verschiedene Prozesse zur Herstellung von Formaldehyd unterschieden. Einerseits wird die oxidative Dehydrierung von Methanol mit Hilfe von Silberkatalysatoren und andererseits die Oxidation von Methanol mit Hilfe von Eisenoxid/Molybdänoxid Katalysa- toren angewandt. Am einzigen österreichischen Standort wird die oxidative Dehydrierung verwendet. Die Ka- pazität dieser Anlage liegt bei 91 000 Tonnen pro Jahr, berechnet als 100 % Formaldehyd. Im Jahr 1998 wurden 83 600 Tonnen produziert, wofür 102 000 Tonnen Methanol als Roh- material benötigt wurden. Nach der katalytischen Umsetzung von Methanol an den Silberkatalysatoren werden die Re- aktionsgase rasch abgekühlt, um eine Zersetzung des gebildeten Formaldehyds zu verhin- dern. Die...
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THE VAPRO PRESSURE OF ENVIRONMENTALLY SIGNIFICANT ORGANIC CHEMICALS: AREVIEW OF METHODS AND DATA AT AMBIENT TEPERATURE
Much attention has increasingly been paid on safety, health and environmental issues, not only in industry but also in the university. Small scale experiments are safer in lowering the risk of chemical contact, more environmentally friendly, produce less waste and gain many other benefits. Although several universities are familiar with small scale chemistry and some universities have operated small scale chemistry laboratories successfully, several other universities have not yet adopted these practices, particularly for organic chemistry laboratory. Due to the nature of the organic chemistry laboratory which is more complicated than the general chemistry laboratory, many kinds of special...
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Environmental, Health and Safety Guidelines for Large Volume Petroleum-based Organic Chemicals Manufacturing
The Environmental, Health, and Safety (EHS) Guidelines are technical reference documents with general and industry- specific examples of Good International Industry Practice (GIIP) 1. When one or more members of the World Bank Group are involved in a project, these EHS Guidelines are applied as required by their respective policies and standards. These industry sector EHS guidelines are designed to be used together with the General EHS Guidelines document, which provides guidance to users on common EHS issues potentially applicable to all industry sectors. For complex projects, use of multiple industry-sector guidelines may be necessary. A complete list of industry-sector guidelines...
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EXPERIMENTAL ORGANIC CHEMISTRY
A study to measure indoor concentrations and emission rates of volatile organic compounds (VOCs), including formaldehyde, was conducted in a new, unoccupied manufactured house installed at the National Institute of Standards and Technology (NIST) campus. The house was instrumented to continuously monitor indoor temperature and relative humidity, heating and air conditioning system operation, and outdoor weather. It also was equipped with an automated tracer gas injection and detection system to estimate air change rates every 2 h. Another automated system measured indoor concentrations of total VOCs with a flame ionization detector every 30 min. Active samples...
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Introduction to Organic Chemistry
The predominant and persistent indoor VOCs included aldehydes (e.g., formaldehyde, acetaldehyde, pentanal, hexanal and nonanal) and terpene hydrocarbons (e.g., a-pinene, 3-carene and d-limonene), which are characteristic of wood product emissions. Other compounds of interest included phenol, naphthalene, and other aromatic hydrocarbons. VOC concentrations were generally typical of results reported for other new houses. Measurements of total VOCs were used to evaluate short-term changes in indoor VOC concentrations. ...
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INVENTORY OF INFORMATION SOURCES ON CHEMICALS
Most of the VOCs probably derived from indoor sources. However, the wall cavity was an apparent source of acetaldehyde, toluene and xylenes and the belly space was a source of 2-butanone, lower volatility aldehydes and aromatic hydrocarbons. Indoor minus outdoor VOC concentrations varied with time. Adjusted formaldehyde concentrations exhibited the most temporal variability with concentrations ranging from 25 µg m-3 to 128 µg m-3 and the lowest concentrations occurring in winter months when indoor RH was low. A model describing the emissions of formaldehyde from urea-formaldehyde wood products as a function of temperature, RH and...
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TOXICITY OF ORGANIC CHEMICALS TO EMBRYO-LARVAL STAGES OF FISH
Indoor exposures to toxic and irritating volatile organic compounds (VOCs) are of general concern. Residences are particularly important exposure environments for these compounds because people in the U.S.A. spend an average of 69 % of their time indoors at home (Klepeis et al., 2001). In addition, residential ventilation rates, which serve as the primary mechanism for removal of gaseous pollutants generated indoors, are relatively low. The median air change rate measured in the 1980s for a large number of houses in the United States was 0.5 h-1 with houses in colder climates and in colder months having...
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School Chemistry Laboratory Safety Guide
In new unoccupied houses, the concentrations of formaldehyde and other VOCs of concern with respect to human health and comfort can be elevated relative to toxicity guidelines and odor thresholds (Hodgson et al., 2000). These gaseous pollutants derive from materials that are widely used to construct and to finish the interiors of houses (Hodgson et al., 2002). Efforts to improve indoor air quality in new houses likely can benefit from further investigation of the sources of VOC contamination and of the dynamic behavior of individual compounds of concern over both relatively short and long time periods. ...
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Organic Chemicals in the Environment
A few studies have provided information on longitudinal trends in VOC concentrations and emissions in new houses (Lindstrom et al., 1995, Hodgson et al., 2002). In four manufactured houses, the area specific emission rates of formaldehyde and hexanal were generally similar at the beginning and end of the 7.5-month study period demonstrating that the sources of these compounds were not depleted rapidly (Hodgson et al., 2000). In existing, occupied residential units, seasonal trends in VOC concentrations have been observed in a cross-sectional study in three German cities and in a longitudinal study of ten apartments (Schlink et al.,...
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Principles of Chemical Nomenclature: A GUIDE TO IUPAC RECOMMENDATIONS
Concentrations of VOCs generated indoors may be presumed to decrease proportionally in response to increases in house ventilation. This has been documented in a new, unoccupied house for those VOCs with the highest vapor pressures (Hodgson et al., 2000). However, within chemical classes, the effectiveness of ventilation for reducing concentrations generally decreases with decreasing volatility (ibid.). The reduced effectiveness of ventilation for controlling the concentrations of less volatile compounds likely is due to sink effects in which the sorption of VOCs on interior surfaces and their diffusion into some materials is reversed when bulk air concentrations start...
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Liquid-Delivery Metal-Organic Chemical Vapour Deposition of Perovskites and Perovskite-Like Compounds
In addition to ventilation, indoor temperature and humidity conditions, which can change both diurnally and seasonally, have the potential to substantially affect the emissions of VOCs from building materials and alter occupant exposure. In large-scale chamber experiments with new carpet systems, sheet vinyl flooring and wall paint, the air temperature was increased from 23 o C to about 30 o C over a period of 60 h (Hodgson, 1999). Concentrations and emissions of the target VOCs quickly increased in response to heating; upon termination of heating, they quickly returned to levels measured in control experiments without additional heating (ibid.). ...
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A REVIEW OF SELECTED PERSISTENT ORGANIC POLLUTANTS
The current study was undertaken in a new manufactured house set up as a research facility. The plan was to conduct longitudinal measurements of VOC concentrations in the house along with measurements of key physical parameters including house air change rate, indoor and outdoor temperature and relative humidity, and wind conditions over a period of approximately one year. The primary objective was to evaluate changes in the emissions of formaldehyde and other VOCs in response to time, house air change rate, and the other parameters. In addition, measurements were conducted to examine the potential influence of unconditioned...
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ORGANIC CHEMISTRY LABORATORY MANUAL
The house is 17.0 m long and 8.2 m wide, with a height of 3.4 m from the ground to the crest of the roof. The floor area is 127 m2 ; the enclosed volume is 310 m3 . The floor plan consists of three bedrooms, two bathrooms and a combined family, kitchen, dining and living area. The subfloor is plywood; 17 % of the floor area is resilient vinyl flooring; 72 % of the floor area is carpeted. The house is unfurnished with the exception of preinstalled kitchen and bath cabinetry and the monitoring equipment (described below)...
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