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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
We prepared our arsenic contaminated standard testing water with level of 100μg/L. Na3AsO4 was added to 1 liter of household water.

Experiment Procedure

  • Four samples of standard water was drawn at 100ml in separate flask
     
  • 3gr of each plant was hand crushed
     
  • Each plant was loosely submerged for 60 minutes in its perspective sample and removed
     
  • Together with the intial standard water, all flasks was prep for shipping.

    We needed the results to be accurately analyzed and certified by a well-known laboratory. Weck Laboratories, Inc. of California U.S. was chosen.


    Experiment Results

    After a few weeks, the results came back from Weck Laboratories as follow:

    Source Arsenic Level
    Contaminated Water 89μg/L

    Adsorbent Arsenic Remains
    Steris Vittata/Fern 3.1μg/L
    Water Hyacinth 3.2μg/L
    Water Lily 3.4μg/L
    Duckweed 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 tooks over 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 concentration 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.

    Both above experiments results have proved Dr. Truyet's theory is correct.
    Certain dried plant can be used effectively as a viable adsorbents in Arsenic reduction.

    We are so excited with the results but as we celebrated, more questions were raised:
    Quantity of plant needed for daily consumption?
    How long does it need to be soaked?
    How long does the plant need to be dried?
    Can the plant be resued?
    .... and so on!

    More tests are needed!.