Propane is used in a number of applications, the most common being a heating fuel. While the Houston heating season is limited, our location, size and industrial.April 6, 2017 Public Health Week Celebrated By Promoting Health Through Partnerships In Orange County The OC Health Care Agency (HCA) celebrated. What change would you most like to see in Jefferson City's public bus system? Cleaning Up Your Criminal Record. If you have been convicted of a crime you may be eligible for relief through a relatively simple legal process. Dargues Gold Mine Information. Priority Existing Chemical Assessment Reports. PEC No. 5. Sodium Ethyl Xanthate. Introduction. Sodium ethyl xanthate (CAS No 1. Minister of Industrial Relations by notice in the Chemical Gazette of 6 July 1. Importers of sodium ethyl xanthate were obliged under section 5. Commonwealth Government's Industrial Chemicals (Notification and Assessment) Act 1. Sodium ethyl xanthate is not manufactured in Australia. Information for assessment was obtained from the applicants, end- users and scientific literature. The AXS Cookie Policy. This website, like most others, uses cookies in order to give you a great online experience. By continuing to use our website you accept to our. Manage your page to keep your users updated View some of our premium pages: google.com. Upgrade to a Premium Page. Sections; Top Stories; Watch; U.S. International; Politics; Lifestyle; Entertainment; Virtual Reality; Health; Tech; Investigative; Sports; Weather; Shows. Applicants ICI Australia Pty Ltd. Nicholson Street. Melbourne VIC 3. 00. Quantum Chemicals Pty Ltd Suite 4 2. Kitchener Parade Bankstown NSW 2. Mineral and Chemical Traders Pty Ltd 5. Parraween Street Cremorne NSW 2. Redox Chemicals Pty Ltd 3. Redfern Street Wetherill Park NSW 2. Mintrade Pty Ltd Level 1 1. Edmonstone Street, South Brisbane QLD 4. Renison Limited Renison Tin Division P O Box 2. Zeehan TAS 7. 46. Chemical identity. Sodium ethyl xanthate is listed in the Australian Inventory of Chemical Substances as carbonodithioic acid, O- ethyl ester, sodium salt, and has a molecular weight of 1. The chemical Abstract Services Number for sodium ethyl xanthate is 1. Use. Sodium ethyl xanthate is used in the mining industry as a flotation agent in the separation of metal sulphides. It is mainly used for the separation of copper, nickel, lead, gold and zinc. During use, the solid sodium ethyl xanthate is mixed with water to form a dilute aqueous solution, and concentrations in the order of 1. The p. H of the aqueous solutions range typically from 7 to 1. Sodium ethyl xanthate is not manufactured in Australia and approximately 2,5. Physical and chemical properties. Sodium ethyl xanthate is a pale yellow amorphous powder with a disagreeable odour due to the presence of carbon disulphide. It has a melting point of 1. The chemical hydrolyses very rapidly under acidic conditions and is stabilised by high p. H conditions. It dissociates totally under p. H 9. Sodium ethyl xanthate is hygroscopic and reacts with water to form carbon disulphide, ethyl alcohol, sodium carbonate and trithiocarbonate. Carbon disulphide is the major decomposition product and has a low autoignition point (9. The physico- chemical properties of carbon disulphide are: odour threshold 0. C; specific gravity 2. L; vapour pressure 4. Pa; flash point - 3. C (closed cup); and is explosive at 1. It reacts strongly with oxidising agents. Decomposition of xanthates. Sodium ethyl xanthate is stable if stored under dry, cool conditions. However, exposure of solid xanthates to moisture and heat causes decomposition and formation of carbon disulphide. The heat generated by hydration or decomposition could raise the temperature to the auto- ignition point of carbon disulphide. Xanthates decompose in aqueous solution by dissociation, oxidation and hydrolysis. Hydrolytic decomposition is the main reaction in alkaline solutions while the other two reactions occur in acidic solutions. Sodium ethyl xanthate is used in the flotation process in alkaline conditions, and therefore the main reaction is hydrolytic decomposition and the major decomposition product is carbon disulphide. Decomposition of xanthates is accelerated at high concentrations and raised temperatures and is also rapid at p. H below 7 and decreases as the p. H increases. Hazard assessment Animal toxicological data. Assessment of sodium ethyl xanthate revealed a lack of published and unpublished toxicity data. The limited and generally poor quality toxicity data creates difficulties in predicting potential human health effects. Toxicity data for other xanthates was included in the assessment for completeness. Sodium ethyl xanthate as a 1. H of 1. 0. 5- 1. 1 has an oral LD5. The target sites are the central nervous system, liver and the spleen. Oral LD5. 0 for other xanthates in mice range from 4. The target sites for the adverse effects of potassium butyl xanthate both after single and repeated oral administration were the central nervous system, liver and kidneys indicating similar target organs for the various xanthates. Sodium ethyl xanthate powder has a dermal LD5. A 1. 0% solution is not a skin irritant. Sodium ethyl xanthate as a powder causes mild to moderate eye irritation in the rabbit, while it is not an irritant in the diluted form (1. Inhalation of potassium amyl xanthate in a 3. The other affected organs were the kidneys in rats and the central nervous system in mice. The target sites for sodium ethyl xanthate, and other xanthates are the central nervous system, liver and kidneys. The adverse effects seen in the toxicity studies could be due to the xanthates themselves, their decomposition products or a combination of both. Human health effects. Limited human health effects information was available for assessment. Contract workers at one mining site reported nausea and residents in the vicinity of a mine using sodium ethyl xanthate complained of headache, dizziness, nausea and foul odour. A chemical leak during transport of sodium ethyl xanthate led to six railway workers being hospitalised after inhaling fumes. The Canadian Centre for Occupational Health and Safety (1. Rakhimova (1. 97. The worker lost consciousness and was removed from the work site. On revival he was restless, vomited and had convulsive twitching of muscles in his arms and legs. He complained of difficult breathing, teary eyes and hoarseness and later developed light sensitivity and fluid accumulation in the eyelids and eye discharge. Classification. In accordance with the health effects criteria detailed in the National Commission's Approved Criteria for Classifying Hazardous Substances (Approved Criteria), sodium ethyl xanthate is classified as 'harmful' by the oral and dermal routes and as an eye and skin irritant. The 1. 0% solution of sodium ethyl xanthate is classified as harmful by the oral route and is not a skin and eye irritant. Based on the classification of its health effects and in accordance with the Approved Criteria sodium ethyl xanthate is considered to be a hazardous substance. The data were insufficient to classify sodium ethyl xanthate for other health hazards such as chronic effects, acute inhalational effects, carcinogenicity and mutagenicity. According to the Australian Code for the Transport of Dangerous Goods by Road and Rail (ADG Code) sodium ethyl xanthate is classified as a dangerous good, Class 4. Carbon disulphide. Carbon disulphide is a dangerous fire and explosion hazard. Carbon disulphide can be absorbed by inhalation, through the skin and by the oral route. Acute exposure to high concentrations (5. Carbon disulphide vapour is a severe irritant to the eyes, skin and respiratory system, and the liquid may cause burns. Repeated exposure to carbon disulphide vapour can adversely affect the central and peripheral nervous systems, including weakening of the leg muscles and damage to the peripheral and cerebral arteries. Carbon disulphide has been shown to contribute towards coronary heart disease in exposed workers, and severe effects on the retina of the eye have been observed. Hearing defects in workers exposed to carbon disulphide have also been reported. Adverse effects on the reproductive system of workers has been noted. Menstrual disorders have been observed in female workers exposed to carbon disulphide levels below 3 ppm for 3 years. Decreased libido was observed in earlier studies while a later study revealed changes in sperm morphology when carbon disulphide levels were believed to be about 1. Data from animal studies are consistent with the observed human health effects. Exposure assessment Occupational exposure. Sodium ethyl xanthate is not manufactured in Australia and hence occupational exposure to sodium ethyl xanthate is limited to workers involved in the transport, use and storage of the chemical. A number of mines in Australia use sodium ethyl xanthate or one of the other alkyl xanthates. Transport and storage. Sodium ethyl xanthate in pellet or powder form is usually imported in 1. The quality of the packaging of the chemical varies from batch to batch. Conditions of storage vary at different mine sites from a fully enclosed area to a large storage shed with only three walls. At some sites storage is in a covered area with only a roof and no walls. One or two workers are involved in the handling and storage of drums at each mining site. There is the greatest potential for worker exposure to xanthate powder or pellets and carbon disulphide vapour during transport and storage if the drums or bulker bags are damaged or not adequately sealed. Sodium ethyl xanthate in contact with moisture produces carbon disulphide. Mixing process. There is a potential for high worker exposure to sodium ethyl xanthate and carbon disulphide, during the mixing process, depending on the degree of automation. During tipping of the drums there is a likelihood of dust generation and spillage of the powder or pellets which could lead to worker exposure. Storage of solution. Potential for exposure during storage of the solution is limited as transfer to the storage and header tanks are through closed pipes. Inhalation exposure could occur due to leaks in the pipes. Flotation. Sodium ethyl xanthate solution enters the flotation cells through closed pipes via a head tank. The solution is gravity fed via control valves and flow meters to addition points within flotation cells. Workers involved in checking flows, the head tank or in adjusting and monitoring the pulp levels in the flotation process could be exposed to the chemical or carbon disulphide. Maintenance. Storage tanks must be cleaned regularly due to the build up of sludge. The frequency of cleaning storage tanks varies from once every three months to once or twice a year at different mines. There is a high potential for dermal and inhalational exposure to both sodium ethyl xanthate and carbon disulphide during the cleaning of storage tanks.
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