Hydrogen Fluoride
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Chemical Storage Cabinets
Storage cabinets Incompatible chemicals must be kept separately to reduce the risk of mixing in case of accidental breakage or response to an emergency within the laboratory. (A starting point is to check the Safety Data Sheet for hazard and storage requirements.) Containers must be kept tightly closed and stored in cabinets which are suitable for the chemical. It is important to check materials which have a shelf life and safely dispose of before the date expires, and generally check the label to ensure it is still suitable and provides the necessary safety information. The condition of the cabinets needs to be checked to ensure that they are providing adequate containment of the materials being stored. Ensure spill trays are used which are capable of holding 110% volume of the largest container being stored in the tray. There may be occasions where the quantities being stored are very small and secondary containment of the chemicals within a cabinet provided would be deemed as providing adequate separation. The table below provides guidance on the type of materials being stored and the type of cabinet which is suitable for that material. This is not a definitive list and does not include ‘Highly Toxic’ materials. Separate guidance is in development. Hazard Group Type of cabinet Safety Sign and suggested Other information Max allowed (where wording applicable) Flammable Liquids Metal flammable storage Flammable liquids must 50 litres of highly flammable cabinet to BS EN 14470- never be stored in a liquid stored in any one E.g. alcohols, toluene, 1:2004, offering minimum refrigerator or freezer laboratory. -
Vibrationally Excited Hydrogen Halides : a Bibliography On
VI NBS SPECIAL PUBLICATION 392 J U.S. DEPARTMENT OF COMMERCE / National Bureau of Standards National Bureau of Standards Bldg. Library, _ E-01 Admin. OCT 1 1981 191023 / oO Vibrationally Excited Hydrogen Halides: A Bibliography on Chemical Kinetics of Chemiexcitation and Energy Transfer Processes (1958 through 1973) QC 100 • 1X57 no. 2te c l !14 c '- — | NATIONAL BUREAU OF STANDARDS The National Bureau of Standards' was established by an act of Congress March 3, 1901. The Bureau's overall goal is to strengthen and advance the Nation's science and technology and facilitate their effective application for public benefit. To this end, the Bureau conducts research and provides: (1) a basis for the Nation's physical measurement system, (2) scientific and technological services for industry and government, (3) a technical basis for equity in trade, and (4) technical services to promote public safety. The Bureau consists of the Institute for Basic Standards, the Institute for Materials Research, the Institute for Applied Technology, the Institute for Computer Sciences and Technology, and the Office for Information Programs. THE INSTITUTE FOR BASIC STANDARDS provides the central basis within the United States of a complete and consistent system of physical measurement; coordinates that system with measurement systems of other nations; and furnishes essential services leading to accurate and uniform physical measurements throughout the Nation's scientific community, industry, and commerce. The Institute consists of a Center for Radiation Research, an Office of Meas- urement Services and the following divisions: Applied Mathematics — Electricity — Mechanics — Heat — Optical Physics — Nuclear Sciences" — Applied Radiation 2 — Quantum Electronics 1 — Electromagnetics 3 — Time 3 1 1 and Frequency — Laboratory Astrophysics — Cryogenics . -
Treating Irrigation Systems with Chlorine 1
Archival copy: for current recommendations see http://edis.ifas.ufl.edu or your local extension office. CIR1039 Treating Irrigation Systems with Chlorine 1 Kati W. Migliaccio, Brian Boman and Gary A. Clark2 Introduction Irrigation systems can become partially or completely clogged from biological growths of bacteria or algae which are often present in surface water and ground water. Bacteria and algae use chemical elements such as nitrogen, phosphorus, sulfur, or iron as nutrient sources to grow and develop (Figures 1 and 2) (Pitts et al., 2003). Thus, irrigation systems that also receive nutrients (such as natural background concentrations in the water or from fertigation) may experience greater rates of clogging. While all irrigation systems should have some Figure 1. Irrigation emitter clogged with algal growth. type of filtration system, this alone cannot effectively Credits: Brian Boman UF/IFAS remove microorganisms. Microorganism growth can result in clogged pipes, fittings, and emission devices of the chlorine chemical must be used to provide an (sprinklers, drippers, spray jets, etc.), decreasing effective water treatment program without damaging water application amounts and reducing application the irrigation system or the agricultural crop. uniformity and efficiency. The results of these are This publication provides a guide for using generally reduced agriculture productivity. A chlorine to treat inhibiting microorganism buildup in chemical method for removing microbial growth is irrigation systems. chlorination. Proper injection methods and amounts 1. This document is CIR1039, one of a series of the Agricultural and Biological Engineering Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date July 1992. -
8.7 Hydrofluoric Acid 8.7.1 General
8.7 Hydrofluoric Acid 8.7.1 General5-6 Hydrogen fluoride (HF) is listed as a Title III Hazardous Air Pollutant. Hydrogen fluoride is produced in 2 forms, as anhydrous hydrogen fluoride and as aqueous hydrofluoric acid. The predominant form manufactured is hydrogen fluoride, a colorless liquid or gas that fumes on contact with air and is water soluble. Traditionally, hydrofluoric acid has been used to etch and polish glass. Currently, the largest use for HF is in aluminum production. Other HF uses include uranium processing, petroleum alkylation, and stainless steel pickling. Hydrofluoric acid is also used to produce fluorocarbons used in aerosol sprays and in refrigerants. Although fluorocarbons are heavily regulated due to environmental concerns, other applications for fluorocarbons include manufacturing of resins, solvents, stain removers, surfactants, and pharmaceuticals. 8.7.2 Process Description1-3,6 Hydrofluoric acid is manufactured by the reaction of acid-grade fluorspar (CaF2) with sulfuric acid (H2SO4) as shown below: → CaF2 H2SO4 CaSO4 2HF A typical HF plant is shown schematically in Figure 8.7-1. The endothermic reaction requires 30 to 60 minutes in horizontal rotary kilns externally heated to 200 to 250°C (390 to 480°F). Dry fluorspar ("spar") and a slight excess of sulfuric acid are fed continuously to the front end of a stationary prereactor or directly to the kiln by a screw conveyor. The prereactor mixes the components prior to charging to the rotary kiln. Calcium sulfate (CaSO4) is removed through an air lock at the opposite end of the kiln. The gaseous reaction products—hydrogen fluoride and excess H2SO4 from the primary reaction and silicon tetrafluoride (SiF4), sulfur dioxide (SO2), carbon dioxide (CO2), and water produced in secondary reactions—are removed from the front end of the kiln along with entrained particulate. -
186 SESSION LAWS [Chap
186 SESSION LAWS [Chap. Sec. 2. This act shall take effect and be in force from and after its passage. Approved April 13, 1925. CHAPTER 187—S. F. No. 984. An act to safeguard the distribution and sale of certain danger- ous caustic or corrosive acids, alkalis, and other substances. Be it enacted by the Legislature of the State of Minnesota: Section 1. Definitions.—That in this act, unless the context or subject-matter otherwise requires, A. The term "dangerous caustic or corrosive substance" means each and all of the acids, alkalis, and substances named below: (a) Hydrochloric acid and any preparation containing free or chemi- cally unneutralized hydrochloric acid (HC1) in a concentration of ten per centum or more; (b) Sulphuric acid and any preparation containing free or chemically unneulralized sulphuric acid (H2SO4) in a concentration of ten per centum or more; (c) Nitric acid or any preparation containing free or chemically unneutralized nitric acid (HNO3) in a concentration of five per centum or more; (d) Carbolic acid (C6H5OH), otherwise known as phenol, and any preparation containing carbolic acid in a concentration of five per centum or more; (e) Oxalic acid and any preparation containing free or chemically unneutralized oxalic acid (H2C2O4) in a con- centration of ten per centum or more; (f) Any salt of oxalic acid and any preparation containing any such salt in a concentration of ten per centum or more; (g) Acetic acid or any preparation con- taining free or chemically unneutralized acetic acid (HC2H3O2) in a concentration of -
Is There an Acid Strong Enough to Dissolve Glass? – Superacids
ARTICLE Is there an acid strong enough to dissolve glass? – Superacids For anybody who watched cartoons growing up, the word unit is based on how acids behave in water, however as acid probably springs to mind images of gaping holes being very strong acids react extremely violently in water this burnt into the floor by a spill, and liquid that would dissolve scale cannot be used for the pure ‘common’ acids (nitric, anything you drop into it. The reality of the acids you hydrochloric and sulphuric) or anything stronger than them. encounter in schools, and most undergrad university Instead, a different unit, the Hammett acidity function (H0), courses is somewhat underwhelming – sure they will react is often preferred when discussing superacids. with chemicals, but, if handled safely, where’s the drama? A superacid can be defined as any compound with an People don’t realise that these extraordinarily strong acids acidity greater than 100% pure sulphuric acid, which has a do exist, they’re just rarely seen outside of research labs Hammett acidity function (H0) of −12 [1]. Modern definitions due to their extreme potency. These acids are capable of define a superacid as a medium in which the chemical dissolving almost anything – wax, rocks, metals (even potential of protons is higher than it is in pure sulphuric acid platinum), and yes, even glass. [2]. Considering that pure sulphuric acid is highly corrosive, you can be certain that anything more acidic than that is What are Superacids? going to be powerful. What are superacids? Its all in the name – super acids are intensely strong acids. -
[email protected] +1-703-527-3887 (International) Website
Date of Issue: 10 May 2016 SAFETY DATA SHEET 1. SUBSTANCE AND SOURCE IDENTIFICATION Product Identifier SRM Number: 3122 SRM Name: Hafnium (Hf) Standard Solution Other Means of Identification: Not applicable. Recommended Use of This Material and Restrictions of Use This Standard Reference Material (SRM) is intended for use as a primary calibration standard for the quantitative determination of hafnium. A unit of SRM 3122 consists of 50 mL of an acidified aqueous solution prepared gravimetrically to contain a known mass fraction of hafnium in a polyethylene bottle sealed in an aluminized bag. The solution contains volume fractions of nitric acid at approximately 1 % to 10 % and hydrofluoric acid at approximately 1 % to 2 %. Company Information National Institute of Standards and Technology Standard Reference Materials Program 100 Bureau Drive, Stop 2300 Gaithersburg, Maryland 20899-2300 Telephone: 301-975-2200 Emergency Telephone ChemTrec: FAX: 301-948-3730 1-800-424-9300 (North America) E-mail: [email protected] +1-703-527-3887 (International) Website: http://www.nist.gov/srm 2. HAZARDS IDENTIFICATION Classification Physical Hazard: Not classified. Health Hazard: Skin Corrosion/Irritation Category 1B Serious Eye Damage/Eye Irritation Category 1 Label Elements Symbol Signal Word DANGER Hazard Statement(s) H314 Causes severe skin burns and eye damage. Precautionary Statement(s) P260 Do not breathe fumes, mists, vapors, or spray. P264 Wash hands thoroughly after handling. P280 Wear protective gloves, protective clothing, and eye protection. P301+P330+P331 If swallowed: Rinse mouth. Do NOT induce vomiting. P303+P361+P353 If on skin (or hair): Remove immediately all contaminated clothing. Rinse skin with water. -
UNITED STATES PATENT of FICE 2,640,086 PROCESS for SEPARATING HYDROGEN FLUORIDE from CHLORODFLUORO METHANE Robert H
Patented May 26, 1953 2,640,086 UNITED STATES PATENT of FICE 2,640,086 PROCESS FOR SEPARATING HYDROGEN FLUORIDE FROM CHLORODFLUORO METHANE Robert H. Baldwin, Chadds Ford, Pa., assignor to E. H. du Pont de Nemours and Company, Wi inington, Del, a corporation of Delaware No Drawing. Application December 15, 1951, Serial No. 261,929 9 Claims. (C. 260-653) 2 This invention relates to a process for Sep These objects are accomplished essentially by arating hydrogen fluoride from monochlorodi Subjecting a mixture of hydrogen fluoride and fluoronethane, and more particularly, separat Inonochlorodifluoromethane in the liquid phase ing these components from the reaction mixture to temperatures below 0° C., preferably at about obtained in the fluorination of chloroform with -30° C. to -50° C., at either atmospheric or hydrogen fluoride, Super-atmospheric pressures, together with from In the fluorination of chloroform in the prest about 0.25 mol to about 2.5 mols of chloroform ence Of a Catalyst, a reaction mixture is pro per mol of chlorodifluoronethane contained in duced which consists essentially of HCl, HF, the mixture and separating an upper layer rich CHCIF2, CHCl2F, CHCls, and CHF3. A method O in HF from a lower organic layer. The proceSS of Separating these components is disclosed in is operative with mixtures containing up to 77% U. S. Patent No. 2,450,414 which involves sep by weight of HF. arating the components by a special fractional It has been found that chloroform is substan distillation under appropriate temperatures and tially immiscible With EIF at temperatures be pressures. -
Cylinder Valve Selection Quick Reference for Valve Abbreviations
SHERWOOD VALVE COMPRESSED GAS PRODUCTS Appendix Cylinder Valve Selection Quick Reference for Valve Abbreviations Use the Sherwood Cylinder Valve Series Abbreviation Chart on this page with the Sherwood Cylinder Valve Selection Charts found on pages 73–80. The Sherwood Cylinder Valve Selection Chart are for reference only and list: • The most commonly used gases • The Compressed Gas Association primary outlet to be used with each gas • The Sherwood valves designated for use with this gas • The Pressure Relief Device styles that are authorized by the DOT for use with these gases PLEASE NOTE: The Sherwood Cylinder Valve Selection Charts are partial lists extracted from the CGA V-1 and S-1.1 pamphlets. They can change without notice as the CGA V-1 and S-1.1 pamphlets are amended. Sherwood will issue periodic changes to the catalog. If there is any discrepancy or question between these lists and the CGA V-1 and S-1.1 pamphlets, the CGA V-1 and S-1.1 pamphlets take precedence. Sherwood Cylinder Valve Series Abbreviation Chart Abbreviation Sherwood Valve Series AVB Small Cylinder Acetylene Wrench-Operated Valves AVBHW Small Cylinder Acetylene Handwheel-Operated Valves AVMC Small Cylinder Acetylene Wrench-Operated Valves AVMCHW Small Cylinder Acetylene Handwheel-Operated Valves AVWB Small Cylinder Acetylene Wrench-Operated Valves — WB Style BV Hi/Lo Valves with Built-in Regulator DF* Alternative Energy Valves GRPV Residual Pressure Valves GV Large Cylinder Acetylene Valves GVT** Vertical Outlet Acetylene Valves KVAB Post Medical Valves KVMB Post Medical Valves NGV Industrial and Chrome-Plated Valves YVB† Vertical Outlet Oxygen Valves 1 * DF Valves can be used with all gases; however, the outlet will always be ⁄4"–18 NPT female. -
Ammonium Bifluoride CAS No
Product Safety Summary Ammonium Bifluoride CAS No. 1341-49-7 This Product Safety Summary is intended to provide a general overview of the chemical substance. The information on the summary is basic information and is not intended to provide emergency response information, medical information or treatment information. The summary should not be used to provide in-depth safety and health information. In-depth safety and health information can be found in the Safety Data Sheet (SDS) for the chemical substance. Names • Ammonium bifluoride (ABF) • Ammonium difluoride • Ammonium acid fluoride • Ammonium hydrogen difluoride • Ammonium fluoride compound with hydrogen fluoride (1:1) Product Overview Solvay Fluorides, LLC does not sell ammonium bifluoride directly to consumers. Ammonium bifluoride is used in industrial applications and in other processes where workplace exposures can occur. Ammonium bifluoride (ABF) is used for cleaning and etching of metals before they are further processed. It is used as an oil well acidifier and in the etching of glass or cleaning of brick and ceramics. It may also be used for pH adjustment in industrial textile processing or laundries. ABF is available as a solid or liquid solution (in water). Ammonium bifluoride is a corrosive chemical and contact can severely irritate and burn the skin and eyes causing possible permanent eye damage. Breathing ammonium bifluoride can severely irritate and burn the nose, throat, and lungs, causing nosebleeds, cough, wheezing and shortness of breath. On contact with water or moist skin, ABF can release hydrofluoric acid, a very dangerous acid. Inhalation or ingestion of large amounts of ammonium bifluoride can cause nausea, vomiting and loss of appetite. -
Hexafluorosilicic Acid
Sodium Hexafluorosilicate [CASRN 16893-85-9] and Fluorosilicic Acid [CASRN 16961-83-4] Review of Toxicological Literature October 2001 Sodium Hexafluorosilicate [CASRN 16893-85-9] and Fluorosilicic Acid [CASRN 16961-83-4] Review of Toxicological Literature Prepared for Scott Masten, Ph.D. National Institute of Environmental Health Sciences P.O. Box 12233 Research Triangle Park, North Carolina 27709 Contract No. N01-ES-65402 Submitted by Karen E. Haneke, M.S. (Principal Investigator) Bonnie L. Carson, M.S. (Co-Principal Investigator) Integrated Laboratory Systems P.O. Box 13501 Research Triangle Park, North Carolina 27709 October 2001 Toxicological Summary for Sodium Hexafluorosilicate [16893-85-9] and Fluorosilicic Acid [16961-83-4] 10/01 Executive Summary Nomination Sodium hexafluorosilicate and fluorosilicic acid were nominated for toxicological testing based on their widespread use in water fluoridation and concerns that if they are not completely dissociated to silica and fluoride in water that persons drinking fluoridated water may be exposed to compounds that have not been thoroughly tested for toxicity. Nontoxicological Data Analysis and Physical-Chemical Properties Analytical methods for sodium hexafluorosilicate include the lead chlorofluoride method (for total fluorine) and an ion-specific electrode procedure. The percentage of fluorosilicic acid content for water supply service application can be determined by the specific-gravity method and the hydrogen titration method. The American Water Works Association (AWWA) has specified that fluorosilicic acid contain 20 to 30% active ingredient, a maximum of 1% hydrofluoric acid, a maximum of 200 mg/kg heavy metals (as lead), and no amounts of soluble mineral or organic substance capable of causing health effects. -
Occupational Exposure to Hydrogen Fluoride
criteria for a recommended standard OCCUPATIONAL EXPOSURE TO HYDROGEN FLUORIDE U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE Public Health Service Center for Disease Control National Institute for Occupational Safety and Health M arch 1976 HEW Publication No. (NIOSH) 7 6 -1 4 3 PREFACE The Occupational Safety and Health Act of 1970 emphasizes the need for standards to protect the health and safety of workers exposed to an ever-increasing number of potential hazards at their workplace. The National Institute for Occupational Safety and Health has projected a formal system of research, with priorities determined on the basis of specified indices, to provide relevant data from which valid criteria for effective standards can be derived. Recommended standards for occupational exposure, which are the result of this work, are based on the health effects of exposure. The Secretary of Labor will weigh these recommen dations along with other considerations such as feasibility and means of implementation in developing regulatory standards. It is intended to present successive reports as research and epide miologic studies are completed and as sampling and analytical methods are developed. Criteria and standards will be reviewed periodically to ensure continuing protection of the worker. I am pleased to acknowledge the contributions to this report on hydrogen fluoride by members of my staff and the valuable constructive comments by the Review Consultants on Hydrogen Fluoride, by the ad hoc committees of the American Academy of Occupational Medicine and the Society for Occupational and Environmental Health, and by Robert B. O'Connor, M.D., NIOSH consultant in occupational medicine.