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Hydrogen fluoride & alkylation
JCHAS-915; No of Pages 3
Hydrogen fluoride & alkylation News & Views
O
n 18 February 2015, an explosion occurred in an air pollution control device at the Exxon-Mobile Torrance Refinery, south of Los Angeles. Debris from the explosion came close to, but did not impact, a large storage tank holding Modified Hydrofluoric Acid. According to the U.S. Chemical Safety and Hazard Investigation Board, ‘‘had the debris struck the tank, a rupture could have been possible, resulting in a potentially catastrophic release of extremely toxic modified HF into the neighboring community.’’ Since the explosion, the citizens of Torrance have been campaigning to remove the hydrofluoric acid and replace it with a safer alternative. Some members of the community would prefer that the refinery completely close. This is a battle that has been waged in many locations. While the details change, the overall argument remains the same – ‘‘the hazards of the chemical are too great to allow its presence in the community.’’ Alkylated hydrocarbon derivatives are a significant component in aviation fuel. The Torrance refinery is the major source of fuel for Los Angeles International Airport. The optimal chemistry for alkylation is hydrogen fluoride. The major alternative, sulfuric acid, is more costly and much less efficient. An alternative to anhydrous HF is the mixture referred to as ‘‘Modified Hydrogen Fluoride’’.
Sulfolane (see structure) is added to anhydrous HF to reduce the vapor pressure. According to the South Coast Air Quality Management District (SCAQMD), ‘‘. . .unique physical properties of the additive substantially reduce the volatility of the acid at ambient conditions. This reduction in volatility proportionately reduces the amount of HF that can vaporize and subsequently disperse off-site from a given liquid release quantity. The modified HF catalyst reduces acid vapor pressure sufficiently to suppress the usual flash atomization process of hydrofluoric acid, causing most of the acid to fall to the ground as an easily controlled liquid and reduces the potential for off-site consequences of an accidental HF release.’’ The refining company, UOP, claims the reduction in vapor dispersion is up to 90%, but no data were presented. It is
1871-5532 http://dx.doi.org/10.1016/j.jchas.2016.09.003
worth noting that extensive searching in Science Direct, SciFinder, and the patent literature failed to identify physical property data on the HF-Sulfolane mixture. This same point is noted in the 9 September 2016 report by Norton Engineering to the SCAQMD.1 The major alternative to HF catalyzed alkylation is sulfuric acid catalyzed alkylation. While the latter greatly reduces the amount of vapor or mist released during a loss of containment event, overall process risk management studies indicate that the markedly increased transportation of sulfuric acid fails to make this substitution an inherently safer option. It is this point that the community seems to not accept. The Norton report makes it very clear that the conversion to a sulfuric acid based technology would be cost-prohibitive, estimated in the range of $100 million USD. No estimate was given of the impact of this capital cost on the price of gasoline in Southern California. It is not clear how this battle will play out. There is little room for compromise on the part of the community. The new owners of the refinery are working with regulators and trying to work with the community, but little progress is apparent. Never discussed in all of the coverage of this on-going disagreement is the role that the Torrance zoning commission has played over the years. The refinery predates most of the residential housing near the plant. The City allowed housing to be built within the impact zone of the refinery. People purchased homes within a line-of-sight of the refinery and had to recognize that the refinery could impact their quality of life. It is tough to place all of the responsibility to mitigate the issue on the refinery. The City and each of the residents made informed choices and are now complaining about the consequences. It seems that emotion needs to be put aside by everyone and a reasonable solution developed. LITHIUM ION BATTERY SAFETY
The many reports of thermal runaway events associated with lithium ion powered devices raises risk mitigation concerns in workplaces. 1
SCAQMD Norton Engineering, Alkylation Technology Study, AQMD-15-5087-005, 9 Sept 2016.
ß 2016 Published by Elsevier Inc. on behalf of Division of Chemical Health and Safety of the American Chemical Society.
1
Whether you operate in an academic lab, an industrial office, or a manufacturing facility, devices powered by lithium ion batteries are ubiquitous. They are also found in most residential locations. Experience proves that a fire associated with these devices is a significant risk. Given that you cannot easily remove them; you must consider implementing some best management practices. Here are some thoughts. Store the device away from direct heat or sunlight. This includes storage in use. For example, putting your cell phone on top of a drying oven while you manipulate glassware in the oven is not a good idea, even if it is convenient. Do not place the battery on or near fires, stoves, or other hightemperature locations. Do not place the battery in direct sunshine, or use or store the battery inside cars in hot weather. Doing so may cause the battery to generate heat, explode, or ignite. Avoid situations which generate and accumulate heat. Do not carry or store the batteries with exposed contacts together with necklaces, hairpins, or other metal objects. Do not solder directly onto the battery. Do not place the battery in fire or heat the battery. Do not place the batteries in microwave ovens, high-pressure containers, or on induction cookware. Do not install the battery backwards so that the polarity is reversed. Do not connect the positive terminal and the negative terminal of the battery to each other with any metal object (such as wire). Devices that have fans for ventilation (e.g. laptops) should not be used where the airflow is blocked. Use forced-cooling pads if you have a high-performance laptop that you use for computation-intensive tasks
2
or gaming. Use the device plugged-in in such cases, so that the battery is not discharging rapidly (causing heating) while running compute-intensive tasks (producing even more heat). Charging and discharging both cause build-up of heat. Pay attention to the temperature of the device and try to keep it within the hand-comfortable range. Prevent mechanical damage to this battery, even though this is unlikely during regular use. Li-ion batteries store a LOT of energy, and crushing or puncturing will cause shorting, resulting in a sudden buildup of a LOT of heat and possibly cause a fire. Do not penetrate the battery with nails, strike the battery with a hammer, step on the battery, or otherwise subject it to strong impacts or shocks. Do not expose the battery to water or salt water, or allow the battery to get wet. Do not disassemble or modify the battery. The battery contains safety and protection devices which, if damaged, may cause the battery to generate heat, explode or ignite. If you see a battery bulging, it can mean only one thing- buildup of gas inside. This strongly suggests a thermal runaway event is imminent. Stop using the device, isolate it in a location that is clear of all ignitable materials, and seek expert assistance, or call the fire department. Do not insert the battery into equipment designed to be hermetically sealed. In some cases, hydrogen may be discharged from the cell which may result in rupture, fire or explosion. Do not use cheap chargers from noname manufacturers. Using a faulty charger can cause dangerous overcharging, and this should be avoided at all costs. Use the charger supplied by the device manufacturer if possible. Use low-current chargers when feasible.
Avoid fully discharging batteries very often. 30%–95% is a good range for best cycle life. If battery fluid contacts your skin or eyes, treat this as a chemical contamination and flush the affected area with large amounts of cool water. Get assistance immediately. In the event of a battery fire, follow your company’s fire response procedures. Isolate the area and get help immediately. Sand or dry powder is the fire suppression medium of choice.
Lithium ion batteries are another hazard found in the workplace. Control the risks by proper handling of all devices which use these energy sources.
U4700 SCHEDULE I DRUG
Commonly known as U4700, the opioid chemical 3,4-Dichloro-N[(1R,2R)-2-(dimethylamino)cyclohexyl]-N-methylbenzamide (see structure) is a selective agonist of the m-opioid receptor. It has a reported potency 7.5 times greater than morphine in animal models. The drug was developed by a research team at Upjohn with a patent issued in 1978. U4700 has recently been implicated in the current opioid overdose epidemic. In response, Ohio issued an emergency restrictive order of 3 May 2016 and the U.S. Drug Enforcement Agency placed it (temporarily) on the Schedule I Controlled Substances List on 7 September 2016. For research programs which are studying this compound, these restrictions place significant barriers for unimpeded research handling. If you are working with U4700 or related opioids, review your protocols to ensure you are consistent with DEA and institutional requirements.
Journal of Chemical Health & September/October 2016
The current opioid overdose epidemic is primarily driven by the misuse of prescription drugs. But synthetic drugs, as the accompanying CDC2 graph shows, play a major role.
2
U.S. Center for Disease Control and Prevention, https://www.cdc.gov/ drugoverdose/data/analysis.html (last visited 22 September 2016). Journal of Chemical Health & Safety, September/October 2016
3
Hydrogen fluoride & alkylation News & Views
O
n 18 February 2015, an explosion occurred in an air pollution control device at the Exxon-Mobile Torrance Refinery, south of Los Angeles. Debris from the explosion came close to, but did not impact, a large storage tank holding Modified Hydrofluoric Acid. According to the U.S. Chemical Safety and Hazard Investigation Board, ‘‘had the debris struck the tank, a rupture could have been possible, resulting in a potentially catastrophic release of extremely toxic modified HF into the neighboring community.’’ Since the explosion, the citizens of Torrance have been campaigning to remove the hydrofluoric acid and replace it with a safer alternative. Some members of the community would prefer that the refinery completely close. This is a battle that has been waged in many locations. While the details change, the overall argument remains the same – ‘‘the hazards of the chemical are too great to allow its presence in the community.’’ Alkylated hydrocarbon derivatives are a significant component in aviation fuel. The Torrance refinery is the major source of fuel for Los Angeles International Airport. The optimal chemistry for alkylation is hydrogen fluoride. The major alternative, sulfuric acid, is more costly and much less efficient. An alternative to anhydrous HF is the mixture referred to as ‘‘Modified Hydrogen Fluoride’’.
Sulfolane (see structure) is added to anhydrous HF to reduce the vapor pressure. According to the South Coast Air Quality Management District (SCAQMD), ‘‘. . .unique physical properties of the additive substantially reduce the volatility of the acid at ambient conditions. This reduction in volatility proportionately reduces the amount of HF that can vaporize and subsequently disperse off-site from a given liquid release quantity. The modified HF catalyst reduces acid vapor pressure sufficiently to suppress the usual flash atomization process of hydrofluoric acid, causing most of the acid to fall to the ground as an easily controlled liquid and reduces the potential for off-site consequences of an accidental HF release.’’ The refining company, UOP, claims the reduction in vapor dispersion is up to 90%, but no data were presented. It is
1871-5532 http://dx.doi.org/10.1016/j.jchas.2016.09.003
worth noting that extensive searching in Science Direct, SciFinder, and the patent literature failed to identify physical property data on the HF-Sulfolane mixture. This same point is noted in the 9 September 2016 report by Norton Engineering to the SCAQMD.1 The major alternative to HF catalyzed alkylation is sulfuric acid catalyzed alkylation. While the latter greatly reduces the amount of vapor or mist released during a loss of containment event, overall process risk management studies indicate that the markedly increased transportation of sulfuric acid fails to make this substitution an inherently safer option. It is this point that the community seems to not accept. The Norton report makes it very clear that the conversion to a sulfuric acid based technology would be cost-prohibitive, estimated in the range of $100 million USD. No estimate was given of the impact of this capital cost on the price of gasoline in Southern California. It is not clear how this battle will play out. There is little room for compromise on the part of the community. The new owners of the refinery are working with regulators and trying to work with the community, but little progress is apparent. Never discussed in all of the coverage of this on-going disagreement is the role that the Torrance zoning commission has played over the years. The refinery predates most of the residential housing near the plant. The City allowed housing to be built within the impact zone of the refinery. People purchased homes within a line-of-sight of the refinery and had to recognize that the refinery could impact their quality of life. It is tough to place all of the responsibility to mitigate the issue on the refinery. The City and each of the residents made informed choices and are now complaining about the consequences. It seems that emotion needs to be put aside by everyone and a reasonable solution developed. LITHIUM ION BATTERY SAFETY
The many reports of thermal runaway events associated with lithium ion powered devices raises risk mitigation concerns in workplaces. 1
SCAQMD Norton Engineering, Alkylation Technology Study, AQMD-15-5087-005, 9 Sept 2016.
ß 2016 Published by Elsevier Inc. on behalf of Division of Chemical Health and Safety of the American Chemical Society.
1
Whether you operate in an academic lab, an industrial office, or a manufacturing facility, devices powered by lithium ion batteries are ubiquitous. They are also found in most residential locations. Experience proves that a fire associated with these devices is a significant risk. Given that you cannot easily remove them; you must consider implementing some best management practices. Here are some thoughts. Store the device away from direct heat or sunlight. This includes storage in use. For example, putting your cell phone on top of a drying oven while you manipulate glassware in the oven is not a good idea, even if it is convenient. Do not place the battery on or near fires, stoves, or other hightemperature locations. Do not place the battery in direct sunshine, or use or store the battery inside cars in hot weather. Doing so may cause the battery to generate heat, explode, or ignite. Avoid situations which generate and accumulate heat. Do not carry or store the batteries with exposed contacts together with necklaces, hairpins, or other metal objects. Do not solder directly onto the battery. Do not place the battery in fire or heat the battery. Do not place the batteries in microwave ovens, high-pressure containers, or on induction cookware. Do not install the battery backwards so that the polarity is reversed. Do not connect the positive terminal and the negative terminal of the battery to each other with any metal object (such as wire). Devices that have fans for ventilation (e.g. laptops) should not be used where the airflow is blocked. Use forced-cooling pads if you have a high-performance laptop that you use for computation-intensive tasks
2
or gaming. Use the device plugged-in in such cases, so that the battery is not discharging rapidly (causing heating) while running compute-intensive tasks (producing even more heat). Charging and discharging both cause build-up of heat. Pay attention to the temperature of the device and try to keep it within the hand-comfortable range. Prevent mechanical damage to this battery, even though this is unlikely during regular use. Li-ion batteries store a LOT of energy, and crushing or puncturing will cause shorting, resulting in a sudden buildup of a LOT of heat and possibly cause a fire. Do not penetrate the battery with nails, strike the battery with a hammer, step on the battery, or otherwise subject it to strong impacts or shocks. Do not expose the battery to water or salt water, or allow the battery to get wet. Do not disassemble or modify the battery. The battery contains safety and protection devices which, if damaged, may cause the battery to generate heat, explode or ignite. If you see a battery bulging, it can mean only one thing- buildup of gas inside. This strongly suggests a thermal runaway event is imminent. Stop using the device, isolate it in a location that is clear of all ignitable materials, and seek expert assistance, or call the fire department. Do not insert the battery into equipment designed to be hermetically sealed. In some cases, hydrogen may be discharged from the cell which may result in rupture, fire or explosion. Do not use cheap chargers from noname manufacturers. Using a faulty charger can cause dangerous overcharging, and this should be avoided at all costs. Use the charger supplied by the device manufacturer if possible. Use low-current chargers when feasible.
Avoid fully discharging batteries very often. 30%–95% is a good range for best cycle life. If battery fluid contacts your skin or eyes, treat this as a chemical contamination and flush the affected area with large amounts of cool water. Get assistance immediately. In the event of a battery fire, follow your company’s fire response procedures. Isolate the area and get help immediately. Sand or dry powder is the fire suppression medium of choice.
Lithium ion batteries are another hazard found in the workplace. Control the risks by proper handling of all devices which use these energy sources.
U4700 SCHEDULE I DRUG
Commonly known as U4700, the opioid chemical 3,4-Dichloro-N[(1R,2R)-2-(dimethylamino)cyclohexyl]-N-methylbenzamide (see structure) is a selective agonist of the m-opioid receptor. It has a reported potency 7.5 times greater than morphine in animal models. The drug was developed by a research team at Upjohn with a patent issued in 1978. U4700 has recently been implicated in the current opioid overdose epidemic. In response, Ohio issued an emergency restrictive order of 3 May 2016 and the U.S. Drug Enforcement Agency placed it (temporarily) on the Schedule I Controlled Substances List on 7 September 2016. For research programs which are studying this compound, these restrictions place significant barriers for unimpeded research handling. If you are working with U4700 or related opioids, review your protocols to ensure you are consistent with DEA and institutional requirements.
Journal of Chemical Health & September/October 2016
The current opioid overdose epidemic is primarily driven by the misuse of prescription drugs. But synthetic drugs, as the accompanying CDC2 graph shows, play a major role.
2
U.S. Center for Disease Control and Prevention, https://www.cdc.gov/ drugoverdose/data/analysis.html (last visited 22 September 2016). Journal of Chemical Health & Safety, September/October 2016
3