SPUR 2022: PRODUCTION OF CACO3 THROUGH CO2 MINERALIZATION BASED ON PHOSPHOGYPSUM WASTE

Mentor Name:
Xuming Wang

Mentor Position:
Research Professor

Department:
Materials Science & Engineering

College:
Mines & Earth Sciences

Email:
x.wang@utah.edu


Project Description:

**This project is a part of the Summer Program for Undergraduate Research (SPUR), which provides undergraduate students with an intensive 10-week research experience under the mentorship of a University of Utah faculty member. SPUR 2022 begins on May 25 and ends on August 4. If you are interested in this project, please review all program information on the SPUR site. If you wish to apply to this project, you must apply using the SPUR 2022 application.**

Phosphogypsum is a waste product from the phosphate industry. Global phosphogypsum (PG) generation is estimated at 200 Mt/a (Parreira, Kobayashi and Silvestre, 2003; Yang et al., 2009), but only about 15 percent is recycled as building materials, agricultural fertilizers, or soil stabilization amendments (Tayibi, Choura and Lopez, 2009). The United States Environmental Protection Agency has banned most applications of phosphogypsum having a 226Ra concentration of greater than 10 picocurie/gram (0.4 Bq/g). As a result, phosphogypsum which exceeds this limit is stored in large stacks. Central Florida has a large quantity of phosphate deposits, particularly in the Bone Valley region. As a result, there are about 1 billion tons of phosphogypsum stacked in 25 stacks in Florida (22 are in central Florida) and about 30 million new tons are generated each year. The transformation of CO2 into a precipitated mineral carbonate is considered a promising option for carbon capture and storage since the captured CO2 can be stored permanently and industrial wastes can be recycled and converted into value-added carbonate materials. Carbon mineralization as a strategy to both sequester CO2 and liberate energy-relevant minerals represents a significant opportunity to address the growing need for these minerals while concurrently contribution to a reduction in greenhouse gases. This proposal will use phosphogypsum (PG) waste for CO2 mineralization to produce high quality CaCO3 and recover the REE and radionuclides from phosphogypsum (PG).



Opportunity Type:

This is a paid research position


Student Role:

Student will participate the experimental design and conducting experiments. Proposed research will include phophogypsum dissolution and CO2 mineral carbonation process. In this process the phosphogypsum will be dissolved into solution and obtain a Ca rich solution. Solid product will be separated from lixivium. The carbonation process is performed by adding NH4OH and CO2 into remaining leach solution. After the desired reaction time, the solution is filtered to recover CaCO3 which will be dried under 80 OC. Most experiments will involve in the dissolution/ leaching and solution reactions.


Student Benefits:

Student will gain the research experiences in materials science and chemical engineering, including the experimental design, procedure development, material characterization, data analysis. These skills will prepare student for future careers in industry and/or to advance their academic degree.


Project Duration:

35-40 hours per week on research and program-related activities, begins May 25, 2022, and ends August 4, 2022


Minimum Requirements:

Admission to the program is competitive. Applicants must meet all of the following criteria: 1) be a matriculated, degree-seeking undergraduate student in the Fall 2022 semester (beginning or continuing college career in Fall 2022 and not graduating before December 2022; concurrent enrollment while in high school does not meet this eligibility requirement). Applicants do not need to be a University of Utah student. 2) eligible to work in the United States: If you are a University of Utah Dreamer (with or without DACA), you are eligible to participate. U Dreamers with DACA will be hired and paid through U payroll. U Dreamers without DACA who graduated from a Utah high school will be compensated via a different mechanism. If you are a Dreamer from a different institution: If you have DACA, you are eligible to participate and will be hired and paid though U payroll. If you do not have DACA, you are able to participate and gain research experience, but we do not currently have a mechanism that allows us to compensate you. For more information, please contact Megan Shannahan at megan.shannahan@utah.edu or 801-581-2478. If you are an international student or scholar, you must either a) be a degree-seeking undergraduate student at the University of Utah, OR b) possess documentation that establishes your eligibility to work in the United States (if you hold US citizenship, it is likely you have these documents). 3) able to commit to approximately 35-40 hours per week of employment at the University of Utah for the entire duration of the program (May 25-August 4, 2022). 4) at least 18 years old by May 23, 2022 (required if you wish to use on-campus housing; preferred if you will not be using on-campus housing).