Evaporators are a common sight in virtually any laboratory. “Everyone is evaporating off solvents,” says Jeff Reid, product specialist for evaporation at BUCHI (New Castle, DE). That includes everything from academic and environmental labs to the chemical and pharmaceutical industries. So anyone who wants to dry something down to a powder, recrystalize a sample, or recycle a solvent needs an evaporator.
“More people are finding uses for evaporators,” says Jim Jacso, director of sales and engineering at Glas-Col (Terre Haute, IN). “For instance, some biologists use evaporators to dry down well plates.” He adds, “The pharmaceutical industry uses evaporators for many things, such as drying down compounds.” Jacso also notes growth in evaporator use in the food and beverage industry. “There’s an increased demand for them to make sure that there are no residues, such as pesticides, in the foods that we’re consuming.”
“The technology is very mature,” says John Pollard, director of sales at BUCHI, “so the real trends are in the usage of the products.” He adds, “[As with] many other products in the marketplace, customers want automation, automation, automation.” As Pollard says, “A user wants to start the evaporator, walk away, and come back and have the process completed.”
Jacso adds, “There is always talk about helping the end user do the research in the minimum amount of time.” He adds, “We develop our evaporators so the researcher spends less time standing around [waiting] for the process to finish.”
Researchers save the most time by taking advantage of rotary evaporators that have individualized, preprogrammed parameter settings, says Nicole Kvasnicka, product marketing manager at Heidolph North America (Elk Grove Village, IL). She adds, “Lots of customers request digital displays on the units to control all parameters such as bath temperature and rotation speed.” She also points out the requests for reduced process time and says, “Heidolph is releasing a new unit called the Distimatic, which provides automated evaporation 24/7. What’s unique about the product is its automatic residue drainage that allows you to distill large volumes in a continuous and unattended way.” She adds, “This is a product that is not currently out on the market, and we find that [there] is a need in labs so that researchers can optimize their daily workflow.”
The automation in evaporators can also extend to safety. “You can automate our units to lift the flask out of the bath if needed,” says Pollard. “That way you can walk away and not worry about the unit being damaged.” Such features used to exist only on high-end evaporators. “Some of these features are making their way down in terms of price,” Pollard says. “Plus, if you don’t need or can’t afford these features today, you can add them on later.”
Some of today’s evaporators also give users options to be much more environmentally friendly. For example, Jacso mentions that Glas- Col has developed evaporators that reduce the consumption of nitrogen. “We also have a new one that allows customers to recapture solvents,” he says. “We’re hearing a lot that companies are getting more strict about what they’re sending up their stacks.”
Evaporators can also be more green by being more efficient. Evaporators could save energy, for instance, if the technology “knew” how long it needed to run. For example, Jacso says, “We’re coming out with new end-point [detectors]. So the concentration goes only to some level, which you establish by monitoring the level in the tubes.”
Rotated, not stirred
Sometimes the concept of a laboratory goes beyond science, and that really happens with rotary evaporators, which now show up in kitchens and bars. In so-called molecular cooking, chefs often use a rotary evaporator to make sauces and other delectable concoctions.
For example, Kvasnicka says that their rotary evaporators are “used from creating dishes in five-star restaurants to [mixing] unique cocktails.” She adds, “University culinary courses are now using rotary evaporators.”
So the next time you order a cocktail, maybe you should add “Rotated, not stirred.”
An evaporator should last a long time in almost any lab. “We’re in hard economic times,” says Pollard, “and people are trying to get as much value as they can afford.” He adds, “They might not have funding for a new evaporator, so they are looking at the serviceability of the system, the quality of the system. Is it going to last ten to fifteen years?”
Beyond making evaporators last a long time, vendors also make them cost less. When asked about trends in evaporators, Jacso says, “Price. There’s lots of competition out there as far as different models and price ranges.”
In addition to saving money, researchers also want to save space. “The bench space that an evaporator takes is the most important thing that we hear,” Jacso says. “Some researchers are using more personal types of hoods where they want to use an evaporator.” He mentions that some scientists use hoods that are only 24 inches wide and about 15 inches deep, and they want to simultaneously run three to four samples in evaporators. That takes small evaporators.
At the Woods Hole Oceanographic Institution in Massachusetts, assistant scientist Jessica Tierney, Ph.D., uses “evaporators to remove solvent from lipid extracts.” She writes by email, “When buying an evaporator I look for flexibility (e.g., being able to adjust each nozzle on its own), the ability to blow down multiple samples at once, efficiency in terms of using [nitrogen gas, and the] ability to adjust to different vial sizes.”
Whatever uses a scientist plans for an evaporator, some of the same concerns apply in every case. “A buyer should look for quality and craftsmanship as well as the kind of support team that can help you if anything happens,” says Kvasnicka.
For additional resources on evaporators, including useful articles and a list of manufacturers, visit www.labmanager.com/evaporators
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