Chromium Hexavalent Compounds
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Working with Hazardous Chemicals
A Publication of Reliable Methods for the Preparation of Organic Compounds Working with Hazardous Chemicals The procedures in Organic Syntheses are intended for use only by persons with proper training in experimental organic chemistry. All hazardous materials should be handled using the standard procedures for work with chemicals described in references such as "Prudent Practices in the Laboratory" (The National Academies Press, Washington, D.C., 2011; the full text can be accessed free of charge at http://www.nap.edu/catalog.php?record_id=12654). All chemical waste should be disposed of in accordance with local regulations. For general guidelines for the management of chemical waste, see Chapter 8 of Prudent Practices. In some articles in Organic Syntheses, chemical-specific hazards are highlighted in red “Caution Notes” within a procedure. It is important to recognize that the absence of a caution note does not imply that no significant hazards are associated with the chemicals involved in that procedure. Prior to performing a reaction, a thorough risk assessment should be carried out that includes a review of the potential hazards associated with each chemical and experimental operation on the scale that is planned for the procedure. Guidelines for carrying out a risk assessment and for analyzing the hazards associated with chemicals can be found in Chapter 4 of Prudent Practices. The procedures described in Organic Syntheses are provided as published and are conducted at one's own risk. Organic Syntheses, Inc., its Editors, and its Board of Directors do not warrant or guarantee the safety of individuals using these procedures and hereby disclaim any liability for any injuries or damages claimed to have resulted from or related in any way to the procedures herein. -
Sodium Chromate 10 Percent Section 1
Conforms to US OSHA Hazard Communication 29CFR1910.1200 SAFETY DATA SHEET Sodium Chromate 10 percent Section 1. Identification 1.1 Product identifier Product name : Sodium Chromate 10 percent Part no. : AR176, AR376 Validation date : 6/24/2020 1.2 Relevant identified uses of the substance or mixture and uses advised against Material uses : Laboratory use Container type: Dispenser Pack AR176 // Sodium Chromate 10 percent // Artisan Grocott's Methenamine Silver Stain Kit // 65 mL and 115 mL AR376 // Sodium Chromate 10 percent // Artisan Grocott's Methenamine Silver Eosin Stain Kit // 65 mL and 115 mL Reference number: SDS056 1.3 Details of the supplier of the safety data sheet Supplier/Manufacturer : Agilent Technologies, Inc. 5301 Stevens Creek Blvd Santa Clara, CA 95051, USA Tel: +1 800 227 9770 Agilent Technologies Singapore (International) Pte Ltd. No. 1 Yishun Avenue 7 Singapore, 768923 Tel. (65) 6276 2622 Agilent Technologies Denmark ApS Produktionsvej 42 2600 Glostrup, Denmark Tel. +45 44 85 95 00 www.Agilent.com e-mail address of person : [email protected] responsible for this SDS 1.4 Emergency telephone number In case of emergency : CHEMTREC®: 1-800-424-9300 Section 2. Hazards identification 2.1 Classification of the substance or mixture OSHA/HCS status : This material is considered hazardous by the OSHA Hazard Communication Standard (29 CFR 1910.1200). Classification of the substance or mixture Date of issue : 06/24/2020 1/15 Sodium Chromate 10 percent Section 2. Hazards identification H302 ACUTE TOXICITY (oral) - Category 4 H311 -
Packet of Wiser Reports on Acetone Acetonitrile
Ac&tone ^Hazmat - NFPA Hazard Classification Page 1 of Acetone CAS RN: 67-64-1 Hazmat - NFPA Hazard Classification SOMS DocID 2085807 Health: 1 (Slight) Materials that, on exposure, would cause significant irritation, but only minor residual injury, including those requiring the use of an approved air-purifying respirator. These materials are only slightly hazardous to health and only breathing protection is needed. Flammability: 3 (Severe) rhis degree includes Class IB and 1C flammable liquids and materials that can be easily ignited under almost all normal temperature conditions. Water may be ineffective in controlling or extinguishing fires in such materials. Instability: 0 (Minimal) This degree includes materials that are normally stable, even under fire exposure conditions, and that do not react with water.- Norma lire fighting procedures may be used. Printed by WISER for Windows (v2.3.231, database v2.108) HHS/NIH, National Library of Medicine AR000018 iile://C:\Documents and Settings\Gham\Application Data\National Library of Medicine\WISER\2.3.231.628... 9/27/20 Acetone ^Key Info Page 1 of Acetone CAS RN: 67-64-1 Key Info FLAMMABLE LIQUIDS (Polar / Water-Miscible) • HIGHLY FLAMMABLE: Easily ignited by heat, sparks or flames • CAUTION: Very low flash point; use of water spray when fighting fire may be inefficient Printed by WISER for Windows (v2.3.231, database v2.108) HHS/NIH, National Library of Medicine AR000019 file://C:\Documents and Settings\Gham\Application Data\National Library of Medicine\WISER\2.3.231.628../ 9/27/20 Acetone - -Hazmat - Explosive Limits / Potential Page 1 of Acetone CAS RIM: 67-64-1 Hazmat - Explosive Limits / Potential Highly flammable liquid. -
Hexavalent Chromium Hexavalent
Toxic Heavy Metals Series Toxic Heavy Metals Hexavalent ChromiumHexavalent This document will familiarize the reader with the toxic metal Hexavalent Chromium, OSHA standards, and methods for prevention and decontamination. Hygenall Corporation 6275 University Drive, STE 37-390 Huntsville, AL 35806 256.781.4486 [email protected] Toxic Metal Series Hexavalent Chromium Contents Introduction . 3 Worker Exposure and Health Consequences . 4 OSHA’s Hexavalent Chromium Standards . 4 Exposure Limits . 4 Exposure Monitoring and Determinations . 4 Scheduled Monitoring Option . 5 Regulated Areas . 6 Control Measures . 7 Requirements for Protective Work Clothing and Equipment . 8 Hygiene Areas and Practices . 9 Housekeeping . 10 Recommended Cleaning and Decontamination Products…11 Medical Surveillance . 12 Worker Training and Communication . 13 Recordkeeping . 14 Effective Dates . 14 Additional Information . 15 References . 16 2 | P a g e Hexavalent Chromium Toxic Metal Series INTRODUCTION This document is intended to give readers an overview of the provisions and requirements of the OSHA Hexavalent Chromium standards for general industry (29 CFR 1910.1026), shipyards (29 CFR 1915.1026), and construction (29 CFR 1926.1126). Hexavalent chromium (Cr(VI)) is a toxic form of the element chromium. Hexavalent chromium is rarely found in nature and is generally man-made. Cr(VI) is widely used in pigments, metal finishing electroplating), wood preservatives and fungicides, and in chemical synthesis as an ingredient and catalyst. Table 1 lists some selected Cr(VI) compounds with their synonyms and common uses. Hexavalent chromium may also be present in fumes generated during the production or welding of chrome alloys. Chromium metal is often alloyed with other metals or plated on metal and plastic substrates to improve corrosion resistance and provide protective coatings. -
Wood Modified by Inorganic Salts: Mechanism and Properties
WOOD MODIFIED BY INORGANIC SALTS: MECHANISM AND PROPERTIES. I. WEATHERING RATE, WATER REPELLENCY, AND IIIMENSIONAL STABILITY OF WOOD MODIFIEID WITH CHROMIUM (111) NITRATE VERSUS CHROMIC ACID' R. S. Willianzs and W. C. Feisl Research Chemists Forest Products Lab~ratory,~Forest Service U.S. Department of Agriculture Madison, WI 53705 (Received October 1983) ABSTRACT Chromic acid treatment of wood improves surface characteristics. A simple dip or brush application of 5% aqueous chromic acid to a wood surface stops extractive staining, improves dimensional stability, retards weathering of unfinished wood, and prolongs the life of finishes. A better understanding of how chromic acid effects these improvements may facilitate the development of even better treatments. The improvements may be due to a combination offactors: oxidation ofwood by hexavalent chromium compounds, formation of coordination coml~lexeswith trivalent chromium, and the presence of insoluble chromium compounds at the surface. Most trivalent chromium compounds do not become fixed in wood (i.e., do not form water-insolublf: wood-chemical complexes). However, chromium (111) nitrate treatment of western redcedar (Thuja plicata), southern pine (Pinus sp.), and ponderosa pine (Pinus ponderosa) produced modified wood with properties similar to chromic acid-treated wood. Evaluation of the chromium (111) nitrate- and chromic acid-modified wood by leaching, Xenon arc- accelerated weathering, and swellometer experiments clearly demonstrated similar fixation, erosion, and water-repellent properties. Based on the results from chromium (111) nitrate-treated wood, fixation through coordination of trivalent chromium with wood hydroxyls an(5 formation of insoluble chromium appear to be the critical factors in improving the performance of the treated wood. -
(VI) and Chromium (V) Oxide Fluorides
Portland State University PDXScholar Dissertations and Theses Dissertations and Theses 1976 The chemistry of chromium (VI) and chromium (V) oxide fluorides Patrick Jay Green Portland State University Follow this and additional works at: https://pdxscholar.library.pdx.edu/open_access_etds Part of the Chemistry Commons Let us know how access to this document benefits ou.y Recommended Citation Green, Patrick Jay, "The chemistry of chromium (VI) and chromium (V) oxide fluorides" (1976). Dissertations and Theses. Paper 4039. https://doi.org/10.15760/etd.5923 This Thesis is brought to you for free and open access. It has been accepted for inclusion in Dissertations and Theses by an authorized administrator of PDXScholar. Please contact us if we can make this document more accessible: [email protected]. All ABSTRACT OF THE TllESIS OF Patrick Jay Green for the Master of Science in Chemistry presented April 16, 1976. Title: Chemistry of Chromium(VI) and Chromium(V) Oxide Fluorides. APPROVEO BY MEMBERS OF THE THESIS CO'"o\l TIEE: y . • Ii . ' I : • • • • • New preparative routes to chromyl fluoride were sought. It was found that chlorine ironofluoride reacts with chromium trioxide and chromyl chlo ride to produce chromyl fluoride. Attempts were ~ade to define a mechan ism for the reaction of ClF and Cr0 in light of by-products observed 3 and previous investigations. Carbonyl fluoride and chromium trioxide react to fom chro·yl fluoride and carbo:i dioxide. A mechanism was also proposed for this react10n. Chromium trioxide 11itl\ l~F6 or WF5 reacts to produce chromyl fluoride and the respective oxide tetrafluoride. 2 Sulfur hexafluoride did not react with Cr03. -
Chromium Compounds Hazard Summary
Chromium Compounds Hazard Summary Chromium occurs in the environment primarily in two valence states, trivalent chromium (Cr III) and hexavalent chromium (Cr VI). Exposure may occur from natural or industrial sources of chromium. Chromium III is much less toxic than chromium (VI). The respiratory tract is also the major target organ for chromium (III) toxicity, similar to chromium (VI). Chromium (III) is an essential element in humans. The body can detoxify some amount of chromium (VI) to chromium (III). The respiratory tract is the major target organ for chromium (VI) toxicity, for acute (short-term) and chronic (long-term) inhalation exposures. Shortness of breath, coughing, and wheezing were reported from a case of acute exposure to chromium (VI), while perforations and ulcerations of the septum, bronchitis, decreased pulmonary function, pneumonia, and other respiratory effects have been noted from chronic exposure. Human studies have clearly established that inhaled chromium (VI) is a human carcinogen, resulting in an increased risk of lung cancer. Animal studies have shown chromium (VI) to cause lung tumors via inhalation exposure. Please Note: The main sources of information for this fact sheet are EPA's Integrated Risk Information System (IRIS) (7), which contains information on inhalation chronic toxicity and the RfC and oral chronic toxicity and the RfD, and the carcinogenic effects of chromium including the unit cancer risk for inhalation exposure, EPA's Toxicological Review of Trivalent Chromium and Toxicological Review of Hexavalent Chromium (3), and the Agency for Toxic Substances and Disease Registry's (ATSDR's) Toxicological Profile for Chromium. (1) Uses The metal chromium is used mainly for making steel and other alloys. -
Coast Guard, DHS Pt. 150, App. I
Coast Guard, DHS Pt. 150, App. I APPENDIX I TO PART 150—EXCEPTIONS Member of reactive group Compatible with TO THE CHART Propylene glycol (20) (a) The binary combinations listed below Oleum (0) ............................... Hexane (31) have been tested as prescribed in Appendix Dichloromethane (36) III and found not to be dangerously reactive. Perchloroethylene (36) These combinations are exceptions to the 1,2-Propylene glycol (20) ...... Diethylenetriamine (7) Compatibility Chart (Figure 1) and may be Polyethylene polyamines (7) Triethylenetetramine (7) stowed in adjacent tanks. Sodium dichromate, 70% (0) Methyl alcohol (20) Member of reactive group Compatible with Sodium hydrosulfide solution Methyl alcohol (20) (5). Acetone (18) .......................... Diethylenetriamine (7) Iso-Propyl alcohol (20) Acetone cyanohydrin (0) ....... Acetic acid (4) Sulfuric acid (2) ..................... Coconut oil (34) Acrylonitrile (15) ..................... Triethanolamine (8) Coconut oil acid (34) Palm oil (34) 1,3-Butylene glycol (20) ......... Morpholine (7) Tallow (34) 1,4-Butylene glycol (20) ......... Ethylamine (7) Sulfuric acid, 98% or less (2) Choice white grease tallow Triethanolamine (8) (34) gamma-Butyrolactone (0) ...... N-Methyl-2-pyrrolidone (9) Caustic potash, 50% or less Isobutyl alcohol (20) (b) The binary combinations listed below (5). Ethyl alcohol (20) have been determined to be dangerously re- Ethylene glycol (20) active, based on either data obtained in the Isopropyl alcohol (20) Methyl alcohol (20) literature or on laboratory testing which has iso-Octyl alcohol (20) been carried out in accordance with proce- Caustic soda, 50% or less (5) Butyl alcohol (20) dures prescribed in Appendix III. These com- tert-Butyl alcohol, Methanol binations are exceptions to the Compat- mixtures ibility Chart (Figure 1) and may not be Decyl alcohol (20) stowed in adjacent tanks. -
Chemical Resistance Chart
CHEMICAL RESISTANCE CHART CHEMICAL RESISTANCE DATA These recommendations are based upon information from material suppliers and careful examination of available published information and are believed to be accurate. However, since the resistance of metals, plastics and elastomers can be affected by concentration, temperature, presence of other chemicals and other factors. This information should be considered as a general guide rather than an unqualified guarantee. Ultimately, the customer must determine the suitability of the pump used in various solutions. All recommendations assume ambient temperatures unless otherwise noted. RATINGS — CHEMICAL EFFECT FOOTNOTES A — No effect—Excellent 1. P.V.C. — Satisfactory to 72 °F B — Minor effect—Good 2. Polypropylene — Satisfactory to 72 °F C — Moderate effect—Fair 3. Polypropylene — Satisfactory to 120 °F D — Severe effect—Not recommended 4. Nitrile — Satisfactory for “O” Rings 5. Polyacetal — Satisfactory to 72 °F 6. Ceramag — Satisfactory to 72 °F The ratings for these materials are based upon the chemical resistance only. Added consideration must be given to pump selections when the chemical is abrasive, viscous in nature, or has a Specific Gravity greater than 1.1. NOTE: The materials shown below in BOLDFACE TYPE are used in the construction of Little Giant chemical pumps. ” 302 Stainless Steel 304 Stainless Steel 316 Stainless Steel 440 Stainless Steel Aluminum TITANIUM C276 NICKEL ALLOY Cast Bronze Brass Cast Iron Carbon Steel 1) PVC (Type (E-3606) Tygon PTFE Polyacetal Nylon ABS Thermoplastic -
CHEMICAL STORAGE SEGREGATION GUIDELINES Incompatible Chemicals Should Always Be Handled and Stored So That They Do Not Accidentally Come in Contact with Each Other
Laboratory Safety Reminders January 2007 ♦ Mount Holyoke College – Environmental Health and Safety CHEMICAL STORAGE SEGREGATION GUIDELINES Incompatible chemicals should always be handled and stored so that they do not accidentally come in contact with each other. This list is not complete, nor are all compatibilities shown. These materials can react to produce excessive heat, harmful vapors, and/or other deadly reactions. Always know the hazards and incompatibilities of a chemical before using it. Chemicals Avoid Accidental Contact With Acetic acid Chromic acid, nitric acid, permanganates, peroxides Hydroxyl-containing compounds such as perchloric acid, Acetic anhydride ethylene glycol Concentrated nitric acid and sulfuric acid mixtures, peroxides (i.e. Acetone peracetic acid solution, hydrogen peroxide) Acetylene Chlorine, bromine, copper, silver, fluorine, mercury Alkali, alkaline earth and strongly electropositive metals (powered Carbon dioxide, carbon tetrachloride and other chlorinated aluminum, magnesium, sodium, hydrocarbons potassium) Mercury, chlorine, calcium hypochlorite, iodine, bromine, hydrogen Ammonia (anhydrous) fluoride Acids, metal powders, flammable liquids, chlorates, nitrates, sulfur, Ammonium nitrate finely divided organics, combustibles Aniline Nitric acid, hydrogen peroxide Arsenical compounds Any reducing agent Azides Acids Ammonia, acetylene, butadiene, butane, other petroleum gases, Bromine sodium carbide, turpentine, benzene, finely divided metals Calcium oxide Water Carbon activated Calcium hypochlorite, other -
APPENDIX G Acid Dissociation Constants
harxxxxx_App-G.qxd 3/8/10 1:34 PM Page AP11 APPENDIX G Acid Dissociation Constants § ϭ 0.1 M 0 ؍ (Ionic strength ( † ‡ † Name Structure* pKa Ka pKa ϫ Ϫ5 Acetic acid CH3CO2H 4.756 1.75 10 4.56 (ethanoic acid) N ϩ H3 ϫ Ϫ3 Alanine CHCH3 2.344 (CO2H) 4.53 10 2.33 ϫ Ϫ10 9.868 (NH3) 1.36 10 9.71 CO2H ϩ Ϫ5 Aminobenzene NH3 4.601 2.51 ϫ 10 4.64 (aniline) ϪO SNϩ Ϫ4 4-Aminobenzenesulfonic acid 3 H3 3.232 5.86 ϫ 10 3.01 (sulfanilic acid) ϩ NH3 ϫ Ϫ3 2-Aminobenzoic acid 2.08 (CO2H) 8.3 10 2.01 ϫ Ϫ5 (anthranilic acid) 4.96 (NH3) 1.10 10 4.78 CO2H ϩ 2-Aminoethanethiol HSCH2CH2NH3 —— 8.21 (SH) (2-mercaptoethylamine) —— 10.73 (NH3) ϩ ϫ Ϫ10 2-Aminoethanol HOCH2CH2NH3 9.498 3.18 10 9.52 (ethanolamine) O H ϫ Ϫ5 4.70 (NH3) (20°) 2.0 10 4.74 2-Aminophenol Ϫ 9.97 (OH) (20°) 1.05 ϫ 10 10 9.87 ϩ NH3 ϩ ϫ Ϫ10 Ammonia NH4 9.245 5.69 10 9.26 N ϩ H3 N ϩ H2 ϫ Ϫ2 1.823 (CO2H) 1.50 10 2.03 CHCH CH CH NHC ϫ Ϫ9 Arginine 2 2 2 8.991 (NH3) 1.02 10 9.00 NH —— (NH2) —— (12.1) CO2H 2 O Ϫ 2.24 5.8 ϫ 10 3 2.15 Ϫ Arsenic acid HO As OH 6.96 1.10 ϫ 10 7 6.65 Ϫ (hydrogen arsenate) (11.50) 3.2 ϫ 10 12 (11.18) OH ϫ Ϫ10 Arsenious acid As(OH)3 9.29 5.1 10 9.14 (hydrogen arsenite) N ϩ O H3 Asparagine CHCH2CNH2 —— —— 2.16 (CO2H) —— —— 8.73 (NH3) CO2H *Each acid is written in its protonated form. -
A Model of Chromate Leaching from Inhibited Primers
18th World IMACS / MODSIM Congress, Cairns, Australia 13-17 July 2009 http://mssanz.org.au/modsim09 A model of chromate leaching from inhibited primers Jenkins, D.R. 1 and A.D. Miller 2 1 CSIRO Mathematical and Information Sciences, Locked Bag 17, North Ryde NSW 1670 2 CSIRO Mathematical and Information Sciences, Private Bag No 2, Glen Osmond SA 5064 Email: [email protected] Abstract: We present a model of the production, transport and reaction of various ionic species involved in the process of leaching of chromate ions from primer layers on metal substrates. The polymer primer layers contain a range of filler particles, some of which are inert, while others are “active”, in the sense that they act to inhibit the onset and progression of corrosion in bare metal, in a situation where the primer layer is breached. A key active corrosion inhibitor is chromate ions, usually provided by strontium chromate (SrCrO4) particles in the primer. The chromate ions are formed by dissolution in water, which needs to penetrate the primer layer for this to occur. The ions then leach out to the damage site and react with the metal surface to inhibit corrosion. Unfortunately chromate is carcinogenic and therefore is now banned in various parts of the world. More acceptable alternatives for chromate are being keenly sought. A valuable aspect of chromate ions in their inhibitor role is their ability to relatively rapidly leach out after damage initiation, which is not true of many other inhibitors. However, aspects of the mechanism of chromate leaching through primer layers are not well understood.