Category Archives: Chemistry

Fear and Loathing with Frac Fluids

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There is considerable handwringing over hydraulic fracturing fluids and their potential effects on “the environment”. I use quotes in ironic fashion because I see very little parsing of the issue into relevant components. The chemical insult to the environment is highly dependent on both the substances and the extent of dispersion. But I state the obvious.

There are surface effects at the drill site and there are subsurface effects. A spill on the surface is going to be relatively small due to the limited size of the available tankage on site. I drive by these sites almost daily and can see with my own eyes the scale of the project. A surface spill of materials will be limited in scope.

The subsurface effects are complex, however, and the magnitude of consequences will depend on both the extent of the fluid penetration into aquifers and the nature of the materials in the fluid. Much criticism has been dealt, rightfully I think, over the secrecy claims on the composition of these fluids. The default reply from drillers has rested on trade secrecy. To be sure, the matter of government forcing a company to reveal its art is a serious matter. But the distribution of chemical substances into the environment requires some oversight. Especially when substances are injected into locations where they cannt be readily remediated. The remediation of an aquifer is a serious undertaking which may or may not be effective.

If you want to see what is potentially in frac fluids, go to Google Patents and search “hydraulic fracturing fluid”. A great many patents will be found. This will give the length and breadth of the compositions patented. Of this large list only a few are used in current practice. The potential carrier fluids vary from water to LPG (!). Water is a common component, but brine is said to be preferred. Additives include hydrochloric acid and surfactants. The MSDS documents may be a good source of info. Consider that a substantial threat to ground water may be that it is rendered non-potable rather than outright  toxic.

Academic Lab Due Diligence Post-Sangji

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A colleague and I were discussing the Sangji case off-line and I did what I am pathologically prone to do which is to blurt out suggestions.  I’m passing them along to my other friends out in the ether as a rough guideline to thinking about training and due diligence. My suggestions are merely a watered down version of a typical industrial EH&S SOP.

Due Diligence

Your university EH&S department no doubt has some some form of written policy, but having your own arrangement with your student workers will accomplish two things for you- 1) you will have written and signed documentation on having trained your students to use what you might call, if not “best practices”, then “reasonable and ordinary practices” in the lab, and 2) you will have made it perfectly clear to them what kind of expectations you have in regard to their work practices, open lab times, types of activities they may perform unsupervised by you, and your absolute dedication to lab worker safety.

In a civil or criminal action you will be under court order to surrender your documents in a process called “discovery”. Your attorney, being an officer of the court, is legally obligated to ensure that you surrender all of your documentation related to the action.

So, wouldn’t it be useful to surrender documentation of your diligence in all matters of safety?

Making a student or other lab worker’s activity in your lab contingent upon some basic operating rules is not at all unreasonable. And, if the rules are clearly written with consequences for violation of policies, then everyone knows the expectations.

No one can predict the future. But what you can do is some due diligence. Have a written training program with goals and scope. Run your research students and other coworkers through it every year and have them sign off on their attendance. Put it in a file and hope that you never have to pull it out in self-defense.

Such a program would be a solid basis for your defense attorney to argue that you went to reasonable measures to train students on escape plans, shower and eye wash use, sharps, proper PPE, fire extinguisher use, lab hygiene, proper storage, and special techniques to use when handling reactive/toxic/corrosive/flammable materials.

A policy on the amount of flammable materials you have in your lab space is a good thing as is a policy of segregating chemicals in storage according to their flammability and corrosiveness.

Get a signature from coworkers on the policies as well and file it away. I think this is critical. Give a copy of your policies and training plan to the department chairman.

Possible Blowback

Once you have given instruction on your policies, collected all of the signatures, and neatly filed them away, the hard part begins. You must be consistent in enforcing the policies. You have to tear yourself away from the word processor and make periodic safety inspections. If you’re off to a week-long NSF study session, a proxy should be appointed to monitor your labs.

The last thing you want is to have a plan that crumbles under scrutiny. You want to have a gap free history of due diligence.  Former coworkers may be called to testify as to your enforcement of safety rules. Nothing rings hollow like a safety plan that was constructed only for show.

Benefit

A benefit to all of this due diligence is that you may have actually made your lab a safer place to work and have instilled a level-headed safety mentality in your coworkers. Fancy that.

The Sheri Sangji Case

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Many readers know that research assistant Sheri Sangji died from burns sustained in a laboratory fire in the lab of UCLA professor Patrick Harran. Harran and university Regents are up on felony charges for their part in the incident. I understand that the charges are based on occupational health and safety violations related to the incident.

[The excellent blog Chemjobber has been following this story.  I might add that this blog should be put on your Favorites list if it isn’t already there. The author puts a lot of work into it and it shows.]

Sangji was transferring t-butyllithium when her plastic syringe came apart and a quantity of the pyrophoric solution was splashed on her and ignited. She sustained fatal burns when her clothing caught fire and she died 18 days later.

Syringe techniques are common and the use of plastic syringes in such transfers of lithium alkyls is not unusual or automatically over-dangerous. However, some syringes have what is called a Luer tip where a syringe needle is attached solely by friction.

Another design has a Luer lock where the needle is affixed with a twist of the needle into a friction lock.  The former design, with the tubular tip and no locking mechanism is prone to disconnection under tension and on withdrawl of the needle from the septum on a pressurized bottle, the needle is likely to squirt bottle contents onto the worker. The Luer lock largely prevents this type of accident.

Another failure mode is when the plunger is inadvertantly withdrawn completely from the barrel of the syringe. Minimally, this would release the contents from the barrel, possibly on the operator. If the plunger is pulled completely out while the needle is still in a pressurized bottle, a fountain of liquid may discharge, possibly on the operator.

Syringe plungers with a rubber tip are prone to swelling in organic solvents and may become difficult to move during a single use. If the plunger is pulled with great force, it might release suddenly causing it to come out of the barrel along with the contents.

Other syringes have plungers that provide a seal by plastic-on-plastic pressure. The seal depends on the elasticity of the barrel to accomodate the slightly oversized plunger. These syringes do not come with Luer locks and as such, are not forgiving of less than skillful use.

I do not know exactly what technique Sangji was using. Aldrich distributes literature on the use of a cannula in the transfer of air sensitive liquids. That is fine, but if you want 0.1 to 60 mL of RLi, a syringe is the most expeditious method for delivering a precise aliquot in my opinion.

Experimentalists are often stricken with a cowboy mentality. If you have never had a serious incident with a material, it is easy to get a bit cavalier. But handling metal alkyls is a lot like handling rattle snakes- you have to be careful every single time.

A subsequent post offers suggestions on due diligence for ressearch professors.

Plasma

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Today I found myself peering at the lovely lavender glow of opaque argon plasma through the viewing screen of a gleaming new instrument. The light-emitting 8000 K plasma sits apparently still alongside the conical metal skimmer. Somewhere a Dewar was quietly releasing a stream of argon into a steel tube that was bent in crisp military angles into and through walls and across the busy spaces above the suspended ceiling. Another cylinder quietly blows a faint draught of helium into the collision cell. A chiller courses cooled water through the zones heated by the quiet but savage plasma. Inside a turbo pump labors to rush the sparse gases out of the mass analyzer and into the inlet of the rough pump and up the exhaust stack.

Up on the roof, the heavy and invisible argon spills along the cobbles of roofing stones until it rolls off the roof onto the ground where the rabbits scamper and prairie dogs yap. The helium atoms begin their random walk into space. The argon shuffles anonymously into the breeze and becomes part of the weather.

All of the delicate arrangements; all of the contrivances and computer controls in place to tune and play this 21st century marvel. And a wonderment it is. The ICPMS obliterates solutes into a plasma state and then taps a miniscule stream of the heavy incandescent argon breath that trickles into the vacuous electronic salsa dance hall of the quadrapole.  All the heat and rhythm for the sake of screening and counting atomic ions. What a exotic artifact of anthropology it is. And it all began in a rift zone in Africa millions of years ago.

Bubble bubble, Windows trouble

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The latest rev of Windows 7 and MS office is driving me freaking nuts. Used to be that I could do a graph in Excel and copy it cleanly into Word.  That convenience seems to be absent in the latest rev. What fails to copy are the arrows and text boxes that I add to the graph. Not only do some of them fail to transfer, but the graph reformats and they arrive all cattywompus.

What works is to save the Excel document as a pdf and then cut out the graph and paste it into Word.  Fancy that.

So, Microsoft, if I could make the dollars I pay for software change form inside your bank account, say, from dollars into Congolese francs, I’d do it this moment.

Fox Investigates Chem Labs

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Good God.  Fox News in Philly is now investigating university chemistry labs for “high risk” chemicals.  The shabby quality of this piece is beyond words. The entire thrust is this- Chemicals as bomb raw materials. An invitation to walk right in and grab all the corrosives and explosives you can.

Note the law enforcement images alluding to sinister threats and the fear mongering.  It’s what these people do. Manufacturing consent.

Respecting liquid hydrocarbons as a natural wonder

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I just had a conversation with a colleague who is somewhat mainstream in his/her thinking. The question came up as to why can’t we be energy independent.  What is taking so long with the electric cars and natural gas powered … everything? When can we break away from middle eastern petroleum?

In the public sphere, all I hear are the questioners seeking reassurance that there are energy forms out there that will allow us to maintain our current level of consumption. They rarely put it exactly that way, but that is the heart of the issue.

I think multiple generations of people have failed to appreciate the natural wonder of liquid hydrocarbons. The C7-C10 fractions of petroleum, whether directly from the ground or from a cat cracker or reformer, are the motive basis for most of our ground transportation. These liquid hydrocarbons are of a reasonably low vapor pressure and high enough boiling point to allow their use in everything from go-carts and lawn mowers to automobiles and caterpillars.  Teenagers and grandmothers can pump hydrocarbons into an inexpensive and simple tank for use at ambient pressure and temperature. This liquid has a melting point low enough to make it flowable under nearly all earthly conditions.

The high energy density and the liquid state of gasoline is what makes it nearly perfect for propulsion. The energy density of gasoline is 34.8 mega-Joules per liter (MJ/L), as opposed to 21.2 MJ/L for ethanol.

Yeah, gasoline is cheaper per liter than the bottled water inside the convenience store. That perversion is just a temporary historical aberration. This will change.

Cosmically, hydrocarbons in the C7-C10 range suitable for automotive use are quite scarce in the local stellar neighborhood.  Some small hydrocarbon molecules like methane have been spotted in the gas giant planets and on Titan. But for the most part, the only supply of hydrocarbons we have are found in porous deposits below the surface of the only place we can get to- Earth.

We should appreciate our hydrocarbon resources for the true natural wonder that it is and be a bit more reluctant to squander it.  I doubt we’ll ever find a source of energy that is as cheap and convenient to use with such a high energy density.  Battery technology may get close, but innovation there is a highly specialized art that is beyond the scope of most shade tree mechanics. Common lead acid batteries require material and energy inputs, like everything else, and have somewhat low energy density and a high weight penalty.

Lithium batteries, with their higher energy density require a variety of manufactured and relatively exotic substances. And, they require lithium which is fairly scarce, both cosmically and on earth. We really should be recycling lithium scrap.  Seriously, we need to have great respect and appreciation for lithium as well. There really isn’t enough lithium to support everyone’s high energy density lifestyle.

Pinch Predicted in the Uranium Market

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According to an article in Mineweb, the remaining cold war era uranium will be consumed in the next few years, leaving the nuclear industry with inadequate supply streams from mining.  Thomas Drolet of Drolet & Associates Energy Services, said that in 2010 mining produced 118 million pounds of uranium against a demand of 190 million pounds. Obviously, the balance was made up from decomissioned nuclear weapons stockpiles. The article did not say whether the numbers represented lbs of U or of U3O8. The oxide is commonly cited in relation to uranium mine production.

Drolet suggests that Japan will have to restart ca 30 of its 50 or so reactors in order to meet power demand.

It is my sense that the Fukushima disaster will not be the stake in the heart of nuclear power. The location of the Fukushima plant and a list of easily identifiable design features allowed the initiation and propagation of the incident. While the future of reactor operation in Japan may be stunted, most reactors elsewhere in the world are not located in tsunami flood zones. Regrettably, some are located in fault zones. But the insatiable demand for kilowatt hours will override everything. Commercial fission will continue into the indefinite future.

Return to fundamentals

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As we labor away on our extractive metallurgy project, I continue to marvel at how even complex extraction schemes reduce to the application of fundamental chemistry and basic unit operations. It is crucial to have a comprehensive understanding of the composition of your ore and the fate of the components as they are exposed to unit operations. The extraction of desired metals from your ore requires extensive use of analytical resources in order to keep the process economics in line.

Extractive metallurgy also requires an extensive knowledge of descriptive inorganic chemistry- something that was glossed over when I was in college. When I took undergraduate inorganic chemistry the emphasis was on ligand field theory, group theory application to symmetry and vibrational modes, coordination complex chemistry, etc. Lots of content that took many lecture hours to cover. Basic reaction chemistry was neglected in favor of admittedly elegant theory.

The fun for me (an organikker) has been in learning lots of descriptive inorganic chemistry and inorganic synthesis.

Extractive metallurgy in practice comes down to a relatively short list of operations. Roasting or calcining, comminution & classification, extraction, dissolution, flocculation, frothing, dewatering and filtration, redox transformations, precipitation, and drying.  Since most of the solution work is water based, the main handles you have to pull are temperature, selective solubility, and pH.

My undergrad coursework in inorganic qualitative analysis, specifically the separation schemes, has been very valuable both in terms of benchwork as well as descriptive chemistry.