Expert Forums

Topic: Which desiccants should we use?

posed by 
We are looking for the desiccants. We are trying to remove the vapor in the air as much as possible before it goes into our high-precision spectrometer. But we need to keep the hydrocarbon molecule intact. Which desiccants should we use?
  • Avatar Dave Russell Forum Moderator 32 Posts

    Re: Which desiccants should we use?

    All that I could suggest might be a silica-based absorber, which may or may not tie up hydrocarbons. The desiccant might be the same one that you use in the lab. It would probably be clay, silica gel, or activated alumina. There is a finite capacity, and a quick web search revealed several companies manufacturing desiccants which turn a color when they are exhausted. A quick call to one of their tech services might be helpful. A desiccant vendor I called recommended a 3A or a 4A molecular sieve to trap water but not hydrocarbons. I don't know how well that would work. They also suggested silica gel. So it's your choice.

  • Avatar GopalaKrishnaMurthy H S Community Member 1 Post

    Re: Which desiccants should we use?

    Molecular Sieve 3A should be the best because it has a strong affinity for moisture but does not adsorb hydrocarbons of molecular sizes of ethylene or larger. In fact 3A is used for drying ethylene.
  • Avatar Than Nguyen Community Member 1 Post

    Re: Which desiccants should we use?

    A desiccant is a substance that absorbs water vapor from the air. Typically used in the packaging industry, desiccants are used to eliminate the harmful humidity that could potentially degrade or even destroy products that are sensitive to moisture. The most commonly used desiccants include: • silica gel desiccants • molecular sieve desiccants • montmorillonite clay desiccants Proper protection from moisture is important. To that end, combining our moisture barrier bags with a desiccant is one of the most efficient ways to protect your goods. No matter how effective a moisture barrier bag may be, there is always a possibility that a minute amount of moisture may seep in. The use of desiccants is a smart preventive measure for added protection. For more details the applications for each of these desiccants, please visit: