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A thorough and comprehensive study of different parameters affecting the sorbents prepared by impregnating polyethyleneimine (PEI) on silica for CO 2 capture has been conducted. The CO 2 capture performances of resulting sorbents were evaluated on both packed-bed and fluidized-bed reactors. Obtained results indicated that CO 2 adsorptiondesorption performances of sorbents are greatly affected by the operation temperature in both simulated flue gas from coal fired power plant (SCF) and natural gas combined cycle power plant (NGCC). The optimal adsorption temperatures are from 50 to 80 o C for NGCC flue gas and from 70 to 90 o C for SCF flue gas, while the optimal regeneration temperatures are from 110 to 130 o C for both flue gas. Adsorbent containing 30 to 35 wt% PEI fluidized well with both simulated flue gas and steam. Results from this study revealed that PEI impregnated silica is a promising sorbents for CO 2 capture process, using a fluidized-bed reactor, from both coal-fired power and natural gas combined cycle power plants.

The production of hydrogen from renewable and nonrenewable resources is demonstrated. Catalytic steam reforming, using a rhodium-containing catalyst, is shown to be effective for the conversion of natural gas and n-hexadecane (used as a simulant for diesel fuel). Improved conversion efficiencies can be achieved by performing the reaction at higher temperatures and steam to carbon ratios. The presence of sulfur in the fuel is shown to have a significant inhibiting effect on catalyst performance. Steam reforming of biomass-derived species is less effective when compared with that of simpler compounds such as methane and methanol, because these species decompose to produce tars and chars at temperatures below which steam reforming reactions are effective. Autothermal reforming has been shown to be relatively effective for several biomass-derived species.

Production of hydrogen from natural gas is the most cost-effective and simplest technology for commercial hydrogen generation. Natural gas is also a likely source of hydrogen for residential fuel cell systems, due to its wide availability and ease of conversion via steam methane reforming. Although catalyst technology is available for generating hydrogen from natural gas, the design of new catalysts and new catalytic supports to overcome the limitations associated with ceramic catalyst provides an opportunity to make the conversion of natural gas to hydrogen more cost-effective. In the present study, the performance of Ni-Rh/Al 2 O 3 -CeO 2 -ZrO 2 , Ni-Rh/γ-Al 2 O 3 , and Ni-Pd/γ-Al 2 O 3 catalysts were quantitatively evaluated in terms of activity and stability using appropriate kinetic models. Catalysts were tested as powders and supported on metal foil. Results proved rhodium to be a better active agent than palladium, and catalyst activity was found to increase with the increase in rhodium loading at both atmospheric and elevated pressures. γ-Al 2 O 3 supported rhodium catalysts exhibited a better performance at a much lower rhodium loading than the Al 2 O 3 -CeO 2 -ZrO 2 supported catalysts. Mass and heat transfer advantages of the metallic support over the powder form were also established by studying the performance of this catalyst in both forms to demonstrate the potential for the use of metal structured support to achieve commercially relevant hydrogen production targets at lower residence times.

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To support the field demonstration and development of warm syngas cleanup for chemical applications, this project has worked in parallel toward multiple objectives for different aspects of RTI's warm syngas cleanup technologies. It would be difficult to name every individual who has contributed to this project. Nonetheless, we would like to attempt to recognize the individuals who contributed to the development of the warm CO 2 capture technologies. States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights.Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, ABSTRACTOne of the key obstacles for the introduction of commercial gasification technology for the production of power with Integrated Gasification Combined Cycle (IGCC) plants or the production of value added chemicals, transportation fuels, and hydrogen has been the cost of these systems. This situation is particularly challenging because the United States has ample coal resources available as raw materials and effective use of these raw materials could help us meet our energy and transportation fuel needs while significantly reducing our need to import oil. One component of the cost of these systems that faces strong challenges for continuous improvement is removing the undesirable components present in the syngas.The need to limit the increase in cost of electricity to < 35% for new coal-based power plants which include CO 2 capture and sequestration addresses both the growing social concern for global climate change resulting from the emission of greenhouse gas and in particular CO 2 and the need to control cost increases to power production necessary to meet this social objective. Similar improvements to technologies for trace contaminants are getting similar pressure to reduce environmental emissions and reduce production costs for the syngas to enable production of chemicals from coal that is cost competitive with oil and natural gas.RTI, with DOE/NETL support, has been developing sorbent technologies that enable capture of trace contaminants and CO 2 at temperatures above 400 °F that achieve better capture performance, lower costs and higher thermal efficiency. This report describes the specific work of sorbent development for mercury (Hg), arsenic (As), selenium (Se), cadmium (Cd), and phosphorous (P) and CO 2 removal. Because the typical concentrations of Hg, As, Se, Cd, and P are less than 10 ppmv, the focus has been on single-use sorbents with sufficient capacity to ensure replacement costs are cost effective. The research in this report describes the development efforts which expand this sorbent developm...

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