Desalination and Purification of Water using a Solar Powered Hydrogel Multistage

Student: Kevin Murphy
Table: ENG2
Experimentation location: School, Home
Regulated Research (Form 1c): No
Project continuation (Form 7): Yes




[1]   “Water and Sanitation – United Nations Sustainable Development.” United Nations, United Nations, 

[2]   California-Great Basin, Bureau of Reclamation. “Central California Area Office.” Water Facts - Worldwide Water Supply | ARWEC| CCAO | Area Offices | California-Great Basin | Bureau of Reclamation, 4 Nov. 2020,'s%20water,extracted%20at%20an%20affordable%20cost. 

[3]   Gabriel Filippelli, Indiana University – Purdue University Indianapolis. “Climate Change Threatens Drinking Water Quality Across the Great Lakes.” Discover Magazine, Discover Magazine, 29 Apr. 2020, 

[4]    Robbins, Jim. “Desalination Is Booming as Cities Run out of Water.” Wired, Conde Nast, 26 June 2019, 9:00 AM, 

[5]    “Climate Change.” Amazon Aid Foundation, 25 Feb. 2018,,much%20of%20the%20world's%20biodiversity. 

[6]    May, Sue Chen 26, et al. “How to Filter and Remove Microplastics from Tap Water? - TAPP Water.” USA, 10 Feb. 2021, 

[7]    Reports, Consumer. “You're Literally Eating Microplastics. How You Can Cut down Exposure to Them.” The Washington Post, WP Company, 7 Oct. 2019, 

[8]    Zhao, X., et al. (2019) Architecting highly hydratable polymer networks to tune the water state for solar water purification. American Association for the Advancement of Science, vol. 5, no. 6, doi:10.1126/sciadv.aaw5484.

[9]   Lara, R., et al. (2017) Influence of freezing temperature and deacetylation degree on the performance of freeze-dried chitosan scaffolds towards cartilage tissue engineering. Science Direct, vol. 95, pp. 232-240, ISSN 0014-3057.

[10]   Xu, Z., et al. (2020) Ultrahigh-Efficiency Desalination via a Thermally-Localized Multistage Solar Still. Energy & Environmental Science, vol. 13, no. 3, pp. 830– 839., doi:10.1039/c9ee04122b. 

[11]  Boundless. “Boundless Physics.” Lumen,phase%20of%20a%20given%20substance. 

[12]“Department of Health.” Boil Water Response-Information for the Public Health Professional, Nov. 2018, 


Additional Project Information


Research Plan:

The research plan:

Synthesize hydrogels, build freeze dryer for freeze drying, testing using calorimetry for an approximation, take the next step and use DSC to get a highly accurate measurement of evaporation enthalpy.

Build multistage using goretex as a semipermeable membrane, silicone surrounds and an aluminum plate as an intermediate conductor.

Construct the paraboloidal concentrator to focus the solar energy and power the stage.

Questions and Answers

1. What was the major objective of your project and what was your plan to achieve it? 

The major objective was to design, build and test an adaptable and portable device capable of producing pure clean water efficiently.

       a. Was that goal the result of any specific situation, experience, or problem you encountered?

  I grew up in Ireland where it rains all the time however, when I moved to Australia in the middle of the millennium drought to say I was shocked would be an understatement. However, the water crisis isn't just limited to Australia. It is becoming a global crisis. So this research is an attempt to solve it.

       b. Were you trying to solve a problem, answer a question, or test a hypothesis?

I was trying to solve a problem.

2. What were the major tasks you had to perform in order to complete your project?

I had to build a solar tracking nested paraboloidal concentrator, design a photoresistor circuit for triangulation, synthesize hydrogels, build a freeze-dryer, freeze dry the hydrogels, and construct the multistage.


3. What is new or novel about your project?

       a. Is there some aspect of your project's objective, or how you achieved it that you haven't done before?

My project unites three core ideas, all of which I have my own novel impact on. While freeze dried hydrogels have been used to reduce evaporation enthalpy of water, they have not been freeze dried at -80C so they can have larger pores. While multistages have been used to increase the efficiency of solar evaporation, semipermeable membranes have not been applied to these designs. And while solar energy has been captured to evaporate water, a nested paraboloidal mirror with full range of movement using a photoresistor circuit to track the sun has not.

       b. Is your project's objective, or the way you implemented it, different from anything you have seen?


       c. If you believe your work to be unique in some way, what research have you done to confirm that it is?

I have searched through many research papers in my field and not found anything like it.


4. What was the most challenging part of completing your project?

      a. What problems did you encounter, and how did you overcome them?

I didn't have a freeze dryer to freeze dry the hydrogels. So I tried dehydrating them instead which ultimately failed. So then I built a freeze dryer and used that.

      b. What did you learn from overcoming these problems?

I learned how freeze dryers work

5. If you were going to do this project again, are there any things you would you do differently the next time?

I believe that research is about making mistakes and learning from those mistakes, so for that reason I wouldn't change anything.

6. Did working on this project give you any ideas for other projects? 

I want to try changing the solar tracker to something more dormant that doesn't need energy to run. For this I might install a different solar absorber in its place in the future.

7. How did COVID-19 affect the completion of your project?

It slowed down progress but I was able to bring alot of my research home and work on it there./