Grantee Research Project Results
Final Report: PanCeria NOx Reducing Device: Selective Catalytic Reduction System for Emission Control of Small Off-Road Engines
EPA Grant Number: SU839310Title: PanCeria NOx Reducing Device: Selective Catalytic Reduction System for Emission Control of Small Off-Road Engines
Investigators: Cocker, David , Ramirez, Aaron , Cardenas, Alexis , Benitez, Chris , Tam, Kawai
Institution: University of California - Riverside
EPA Project Officer: Page, Angela
Phase: I
Project Period: February 1, 2018 through January 31, 2019
Project Amount: $15,000
RFA: P3 Awards: A National Student Design Competition for Sustainability Focusing on People, Prosperity and the Planet (2017) RFA Text | Recipients Lists
Research Category: Sustainable and Healthy Communities , P3 Awards , P3 Challenge Area - Chemical Safety
Objective:
The aim of the PanCera prototype is to be an inexpensive catalytic converter for small off-road engines (SOREs) that will reduce air pollution. The device focuses on reducing the concentrations of nitrogen oxide (NO), carbon monoxide (CO), volatile organic compounds (VOCs), as well as particulate matter (PM) emitted through various small off-road engines such as gasoline-powered generators, lawn mowers, and leaf blowers. The development of this device will include the optimization of a non-precious metal catalyst, and the selection of environmentally-friendly and low-cost materials for construction.
The levels of air pollution have continued to increase globally since the industrial revolution. As a result, air quality has deteriorated due to harmful gas emissions such as NOx which lead to smog formation. The increase in smog has started to adversely affect human health by increasing lung and heart complications, causing inflammation of the lungs, and shortening a person's life expectancy. [1] Because of the perilous effects of smog, domestic and international governments have issued legislation with the intentions of reducing smog. [2] Although regulations have been set in place to reduce smog, regulations often focus on automotive, manufacturing, and energy industries. Small off-road engines (SOREs) which are found in various lawn and gardening equipment, specialty vehicles, and airport ground support are often overlooked as major contributors of smog and are scarcely held to any regulations. [3] The California Air Resource Board classifies SOREs as equipment that contain a spark ignition engine with less than 25 horsepower or produce less than 19 kilowatts of gross power, but do not include compression-ignition engines, watercrafts, or recreational vehicles. [3] Although SOREs go overlooked they are used globally, such as generators used for heat and electricity in San Juan, Puerto Rico or a leaf blower used in Vancouver, WA. Reducing the emissions from these sources of air pollution is globally beneficial, which could be implicated in underdeveloped and developing nations where gas and diesel generators are a commonly used power source. PanCeria is capable of reducing NOX and CO pollution resulting in cleaner air.
Summary/Accomplishments (Outputs/Outcomes):
The PanCeria prototype is currently undergoing its first stage of bench-scale testing. Three different copper weight loadings of the Cu/CeO2 catalyst were sythesiszed using the starting reagents of copper (II) nitrate (Cu(NO3)2), cerium oxide (CeO2), and water (H2O). To synthesize the 5% copper weight catalyst, the mass of copper (Cu) in an arbitrary amount of copper (II) nitrate (Cu(NO3)2) was calculated. Using the calculated mass of copper in the copper (II) nitrate, the amount of cerium oxide needed to produce a catalyst where 5% of its weight is copper was determined. This procedure was completed to determine the ratio of copper(II) nitrate and cerium oxide needed to synthesize each copper weight loading (5%, 10%, and 20%) catalyst. Once the ratios were determined, the copper (II) nitrate and cerium oxide were mixed together with water. Three different mixing techniques were utilized which included using a stir rod, a vortex mixer, and a sonicator (60 Amps). Three different mixing techniques were employed, to determine how mixing affects the particle size and shape of the catalyst. These characteristics of the catalyst will be determined in Phase 2 when SEM and XRD techniques are utilized. Moreover, after mixing the copper (II) nitrate and cerium oxide slurry, the catalyst was dried and calcined at 400oC, using a tube furnace. After calination, the Cu/CeO2 catalyst would be ready to be coated onto our ceramic cordierite monolith. The team was able to synthesize and calcine the 5, 10, and 20% copper weight catalysts. In addition to synthesizing the Cu/CeO2 catalysts, the laboratory where the emissions testing would be taking place was relocated to the Atmospheric Processes Laboratory (APL) at the Center for Environmental Research & Technology (CE-CERT). The relocation involved moving the NO gas tank, CO gas tank, and H2 gas tank to APL and retrofitting the appropriate regulators onto the tanks. Moreso, at APL two unoperational gas analyzers were provided which the team worked to restore. The two analyzers were a 48C CO Analyzer and a 42C NO-NO2-NOx Analyzer High Level. The team has successfully restored power to the analyzers and has been able to turn on the analyzers as well as adjust the parameters and menus of the analyzers such as the Range Menu, Averaging Time, Calibration Factors Menu, Calibration Menu, Instrument Controls Menu, Diagnostics Menu, and Alarms Menu. However, currently the analyzers are indicating that there exists not flow rate of gases entering the system, as well as the analyzers not recording any concentrations. Thus, the team in currenyl troubleshooting this issue and is in the midst of checking the tubings and orifices used in the analyzer to ensure that they are not blocked. Therefore, the ana;yszers are not completely operational for emission reduction bench scale testing of the catalyst. Although the team has faced several setbacks in completing the catalytic benchmark testing of 5, 10, and 20% copper solution weight loadings, thorough research was conducted regarding the materials used to construct the PanCeria device including aluminum sheets for the outer casing of the catalytic converter, a thread adapter to connect the catalytic converter to the exhaust port of the SORE, a stainless steel particulate matter (PM) mesh, a 2MgO-2Al2O3-5SiO2S ceramic cordierite monolith which will house the Cu/CeO2 catalyst, and a fiberglass muffler cap to reduce noise pollution. The lab space at CE-CERT has been set up for catalytic bench scale testing. All gas tanks have been placed near the test bench that will be used, both CO and NO analyzers have been calibrated, and all tubing and exhaust lines have been set up for bench scale testing. Weight loadings of 5, 10, and 20% Cu/CeO have been synthesized as well as calcined, and are undergoing bench scale testing.
Conclusions:
The PanCeria prototype was designed to be environmentally-friendly and affordable through careful selection and research of the materials used to develop the device. Through further catalytic testing the device is aimed at lasting the lifetime of the small off-road engine in use.
The objective of phase two is to optimize the PanCeria prototype and determine the lifespan and stability of the Copper over Ceria catalyst. The PanCeria prototype is expected to last the average lifetime of any SORE. To ensure that the catalyst can withstand long-term use, the cordierite covered catalyst will be subjected to accelerated aging. Accelerated aging will be conducted based on the methods outlined in appendix A of the California Evaluation procedures for new aftermarket catalytic converters, where the coated cordierite will be tested for catalytic efficiency following accelerated aging to determine the catalyst lifespan. Real time aging of the catalyst will also be conducted from 1 to 5 years to determine the catalyst shelf life. To optimize the PanCeria device the catalyst will be tested in a humid environment to determine catalyst stability. To efficiently reduce NOX and CO the cordierite dimensions will be optimized following dip coating and catalyst efficiency testing. After the PanCeria device has been optimized, prototype testing will be completed. Followed by the retrofitting of the prototype on several SOREs including generators, lawn mowers, and leaf blowers.
Supplemental Keywords:
environmental sustainability, air-pollution, criteria pollutants, catalysis, human healthP3 Phase II:
PanCeria: Catalytic NO and CO Emission Control Unit for Small Off-road Engines | 2019 Progress Report | 2020 Progress Report | 2021 Progress ReportThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.