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Arsenic Remediation with Dried Plant

Initial Experiment

The Adsorbents
We choose the following four hyperaccumulation plants as Dr. Mai Thanh Truyet suspect they can be a great arsenic adsorbent. Steris Vittata or known as Fern, a ground based plant and Water Hyacinth, Water Lily and Duckweed are water based.

Steris Vittata/Fern
Pteridophytes

Water Hyacinth
Eichhornia Crassipes

Water Lily
Nymphaea

Duckweed
Lemna minor

These plants were collected in various places in the U.S. and Vietnam and sun-dried for approximately three days.

Arsenic Contaminated Standard Water Preparation
1 liter of standard water was prepared with a concentration of 100μg/L arsenic contamination using Na3AsO4 as additive.

Experiment Procedure

  • Four samples of standard water was drawn at 100ml in separate flask
  • Each plant was hand crushed and prepared at 3gr
  • Each plant was loosely submerged in its perspective standard water for 60 minutes

  • The plant was removed afterward and each flask is sealed and ready for shipping together with a sample of standard water.
    To prove our theory is correct, we need the results to be analyzed and certified by a well-known laboratories. Weck Laboratories, Inc. of California U.S. was chosen.

    Experiment Results
    After a week, we got the results back from Weck Laboratories as follow:

    Standard Water
    Steris Vittata/Fern
    Water Hyacinth
    Water Lily
    Duckweed
    89μg/L 3.1μg/L 3.2μg/L 3.4μg/L 3.1μg/L

    See full results

    This certified results far exceeded our expectations!
    These hyperaccumulation plants has been studied for years but as live plants and their rate of adsorption is relatively slow (the fastest confirmed of 70% reduction is 6 months). Using Dr. Truyet's theory of dried plant, our initial experiment has proved to be far quicker and more effective (>95%).

     

    Retest with Field Test Kit

    The cost for analyzed and certified by Weck Laboratories is well deserved but the time waiting for result is in weeks. We search for a quick field test kit and found one by Industrial Test Systems, Inc.

    For our next experiment, we're aiming at simulate an onsite quick test and see if the result is comparable to the result from Weck Laboratories.

    Experiment Procedure
    5 liters standard water were prepared with 100μg/L of arsenic contamination and 50gr of dried water hyacinth was submerged for 1 hr.

     

    Experiment Result

     

    As you can see above, the result is consistent with the Weck Laboratories result. This time, the above experiments has proved using dried plant are performing as Dr. Truyet predicted. It can be used effectively as viable adsorbents as well as reduction in time but more experiments are necessary such as time vs. quantity of adsorbent needed.