Purification Possibilities through the Implementation - PowerPoint Presentation

Slide1

Purification Possibilities through the Implementation

of the Prickly Pear Cactus (Opuntia) Bella Alexander & Kathy Chen

ABSTRACT

MATERIALS & METHODS

Creating

Opuntia

Powder

RESULTS

DISCUSSION

CONCLUSION

Figure 2:

The removal of the inner cactus meat from the waxy outer coating after boiling to be further processed.

Testing Nitrate Concentration

Figure 6:

50 mL of a previously prepared nitrate-water

solution is

added to each beaker filled with 800, 600, 400, and 200 grams of

Opuntia

powder. From left to right.

Figure 3:

The powder has settled to the bottom of the water, making it easy to remove.

ACKNOWLEDGEMENTS

We would like to acknowledge Mrs. Newman for the time and assistance she has dedicated to our project. Thank you!

Since the 1800’s,

our knowledge of water

pollution and

the associated waterborne illnesses have expanded greatly, and this awareness has compelled us to devise numerous decontamination methods. While most are used in conjunction with others, or simply too costly and labor intensive to use at all, the struggle for accessible, clean water continues. If an efficient method to harvest the mucilage of Opuntia (prickly pear cactus) can be developed and successfully used to decontaminate water, this small, ordinary plant may be the solution to our ongoing struggle to bring potable water to 7 billion people.

Figure 1:

The harvest of the

Opuntia

leaf requires the slicing of the pad into strips.

Figure 5:

From left to right; 800 mg, 600 mg, 400 mg, 200 mg. The shade of red determines the nitrate concentration based on the chart provided.

Figure 4:

The comparison of nitrate concentration (ppm) before and after the application of

Opuntia

cactus powder to the various water samples.

Opuntia

, or commonly known as the prickly pear cactus, grows extensively throughout in its native Mexico. Recent research by Dr. Norma

Alcantar of South Florida University has found that the prickly pear cactus, used by indigenous peoples to purify their water, also possesses oil dispersant and anti-bacterial properties. As current water purification techniques either lack certain levels of efficiency or aren’t suited

for implementation in anunderdeveloped environ-ment where water purifi-cation systems are needed most, a powdered form of the prickly pear cactus mucilage may be the low cost, highly effective, and all natural solution we need to supply clean water for all.

Approximately 130 g of raw prickly pear cactus pads were obtained for processing into a fine powder. The needles were removed from the flesh and then the pads were sliced into 2.5x10 cm strips. The cactus was placed in a pot which was then filled with about 500 mL of water. The pads were cooked for approximately 1.5 hours, the purpose of this cooking process being to make the meat inside the pads easily separable from the waxy outer skin. After the pads were thoroughly cooked, they were placed in a freezer for 30 minutes to cool and were removed at room temperature. The cactus was divided through the meat and a paring knife was used to carefully scrape all the

To measure the effectiveness and to determine the optimal amount of cactus powder that would yield the best results, we tested 0.8, 0.6, 0.4, and 0.2 grams of cactus powder per trial in addition to our control of no cactus powder and pure nitrate solution. Based on standards set by the EPA for safe nitrate content in drinking water, we exceeded the 10 mg/L and created a solution using 2 g/L. Nitrate solution was added to each of the trials, three per amount of powder, and then tested for nitrate content after being stirred for 30 seconds and allowing powder to settle.

Despite our predictions, the data from our experiment did not support our hypothesis that the water sample treated with the highest amount of Opuntia cactus powder would result in the largest decrease in nitrate content. In reality, the cactus powder seemed to do just the opposite: the trials with more cactus powdered showed an increase in nitrate content. We performed a T-test on our data and found that all four trials resulted in a p-value of 0.0277, which suggested that there was no difference in effectiveness between the various amounts of Opuntia. There were many flaws within our experiment, for example, allowing the cactus paste to dry on the sides of a glass container made it very difficult to remove. We would have liked to have tested more contaminants to see if the cactus had varying effects on different impurities for a more holistic grasp of its effectiveness in purifying water We plan to purchase larger quantities of cactus as certain amounts yield less powder than one would initially assume. The liquid nitrate test we used was not as accurate as the electric device we had first planned on utilizing. We have accurately identified and evaluated our procedure so that in the future we may obtain more accurate data for better holistic analysis.

inner cactus off of the waxy skin. After all the cactus had been separated, the waxy remains were discarded and the meat was placed into a blender and puréed until it was a smooth consistency. The liquid was placed back into the pot and reduced until it thickened to a paste which was smeared inside of a glass container and left to dry for 36 hours. After the paste had dried completely, it was scraped off the sides and processed in attachment to form 6.69 g of

Opuntia

powder.