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Arsenic Remediation with Dried Plant

Quantity vs. Time Experiment

For this experiment, we want to analyze for 2 things:

  • The time to reduce the arsenic contamination level below 10μg/L (WHO standard).
  • Adsorbent quantity vs. level of contamination.

    Various experiments of contamination level vs. amount of adsorbent was conducted and the results are as follow:

    • Water Hyacinth
    • Water Lily
    • Duckweed
    • Fern

    Water Hyacinth (Eichhornia Crassipes)

    The above graphs show us at 100ppb, it took 45 min for 1gr of water hyacinth to reduce the arsenic level down to ≤ 10μg/L. As you notice, the time also reduce as more water hyacinth was used.

    At 200ppb with 2gr of water hyacinth, it also took 45 min to reduce the arsenic level down to ≤ 10μg/L.

    At 300ppb, it took 45 min to reduce the arsenic level down to ≤ 10μg/L but 4gr of water hyacinth was needed.

    Initial conclusion, an average of 45 min to reduce the arsenic level down to ≤ 10μg/L and more water hyacinth was needed as level of As contamination increases.

    Eichhornia crassipes (commonly known as water hyacinth), is an aquatic plant native to the Amazon basin, and is often a highly problematic invasive species outside its native range. One of the fastest growing plants known, water hyacinth is a free-floating perennial aquatic plant (or hydrophyte) native to tropical and sub-tropical. In their native range these flowers are pollinated by long tongued bees and they can reproduce both sexually and clonally. The invasiveness of the hyacinth is related to its ability to clone itself and large patches are likely to all be part of the same genetic form.

    Water Lily (Nymphaea)

    Nymphaeaceae (commonly called water lilies) is a family of flowering plants. They live as rhizomatous aquatic herbs in temperate and tropical climates around the world. The family contains five genera with about 70 known species. Water lilies are rooted in soil in bodies of water, with leaves and flowers floating on or emergent from the surface.

    Duckweed (Azolla Caroliniana)

    At 100ppb As contamination level and using 2gr of duckweed as adsorbent, it only took 15 min to reduce below WHO (<10ppb) level. As contamination level double, 3gr are needed.

    Duckweed (Lemna minor)

    Duckweed, or water lens, are flowering aquatic plants which float on or just beneath the surface of still or slow-moving bodies of fresh water and wetlands. These plants are very simple, depending on the species, each plant may have no root or may have one or more simple rootlets. One of the more important factors influencing the distribution of wetland plants, and aquatic plants in particular, is nutrient availability. Duckweeds tend to be associated with fertile, even eutrophic conditions. They can be spread by waterfowl and small mammals, transported inadvertently on their feet and bodies, as well as by moving water.

    Fern (Pteridophytes)

    In previous experiments, all adsorbents was sun-dried for 3 days with approximately 10% moisture remain. We have proven Dr. Truyets' theory of dried plant has faster results than live plant. In this experiment, we want to confirm that theory by comparing with a less dried adsorbent.
    A batch of adsorbent was sun-dried for only one day with approximately 50% moisture remain and will be compares with a standard 10% moisture.

    As we predicted, the moisture in the adsorbent does vary the rate of adsorption. We drawn a conclusion that at 10% moisture remaining, it is the optimum dryness condition for the adsorbent.

    Pteridophyte (commonly known as fern) is a member of a group of vascular plants that reproduce via spores and have neither seeds nor flowers. Fern stems are often referred to as "rhizomes", even though they grow underground only in some of the species. Ferns are not of major economic importance, but some are used for food, medicine, ornamentals and even for remediating contaminated soil. They have been the subject of research for their ability to remove some chemical pollutants from the atmosphere.