CERAMIC IN-LINE PARTICLE FILTER FOR HEAVY-DUTY HYDROGEN FUELING STATIONS

This proposal is in response to DOE topic 15c, which seeks novel filter solutions that can demonstrate high hydrogen flow (10 kg/min) at -40°C at 1000 bar pressure with minimum pressure drop. The filter is expected to filter out particulate contaminates that are larger than 5 μm in diameter. The resulting filter along with its filter module design will potentially contribute to the progress towards fast filling of heavy- duty hydrogen fueled electric vehicles. Commercially available filter materials do not have low temperature resistance (polymers), hydrogen tolerance (metals), or otherwise not enough flow rate (ceramic). The innovation of the α-Al2O3 filters proposed by Global Research, is the highly porous and geometrically precise structure, that allows for much higher flow rate than traditional ceramic filters. The overall goal of the proposed SBIR project is to develop and eventually commercialize a cost effective, filter element and filter module design that can reach the required flow rate and operating pressure. The overall objective of phase I project will be to develop a highly porous a flat/ or tubular α-Al2O3 filter element and the construction of the filter module. The hydrogen flow rate of the filter element will be measured with respect to its pore size and mechanical strength. The choice of filter module material will be investigated for long-term operation. In Phase I, flat and tubular α-Al2O3 filter element with higher than 35% porosity will be fabricated. The hydrogen flow rate of these filter element will be measured as well as their mechanical strength. Research activities will be performed to study the effect of thermal processing, choice of particle size on the transport properties and mechanical strength. Due to strictly size exclusion, we expect a >99.9% filter efficiency. However, the filter element’s mechanical integrity in high pressure can be a source of contaminates. As a result, any particles remained in the permeate stream will be collected and evaluated. Filter modules of the flat and tubular filter elements will be designed and improved for filter element support, housing, and long- term operation. Specific quantifiable milestones in Phase I will be hydrogen flow-rate vs pressure drop, and the maximum operating pressure. Besides the use of these in-line filters in heavy-duty hydrogen fueling stations, they can be used for a variety of other applications. For instance, these ceramic filters will have excellent thermal resistance at both low and high temperatures, as well as chemical resistance in corrosive or oxidizing environment. This applies to both gas-phase and liquid-phase filters for particulates. Additional benefits to these filter elements, or supports is their ultra-smooth surface, which allows for nano-meter thin film coatings for various applications such as gas separation, water purification, and fuel cells.