Carbon dioxide is main causes the greenhouse effect and it contributes to global warming. Zeolite NaA is an excellent adsorbent among other materials but its potential as a carbon dioxide adsorption still needs to be developed. Therefore, this research was to synthesize zeolite NaA from rice husk ash under different temperatures and crystallization times. The synthesized zeolite NaA was modified with zinc by an ion exchange method. Adsorbents were tested for the carbon dioxide adsorption at different operating temperatures and flow rates. The results showed that the zeolite NaA was successfully synthesized from rice husk ash under optimal conditions of the crystallization temperature at 333.15 K and time for 2 h. The zeolite NaA can be synthesized at low crystallization temperature and time resulted in this adsorbent has low cost while achieving high efficiency. The results of zeolite NaA modification with zinc playing a key role to increase the BET surface area, micropore volume and total pore volume resulted in an increase of carbon dioxide adsorption capacity. High carbon dioxide adsorption at 89.08% with the operating temperature at 573.15 K and carbon dioxide flow rate of 1 L/h were shown with 5 wt.% zeolite NaA.

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This research investigated the effects of compression force, compression time, and addition of bentonite binder on zeolite 5A pelletization. Carbon dioxide (CO2) adsorption of zeolite 5A pellets was tested in a laboratory-scale packed-bed reactor at 298 K, atmospheric pressure and 2 l/h flow rate. Zeolite 5A pellets were prepared using a pelletization technique at 200-400 MPa compressive force, 5-15 min compression time, and with 0-15% wt. of bentonite binder. The specific surface area and density of zeolite 5A pellets increased with increase of compression force. Compression force led to increase in specific surface area and resulted in an agglomeration of zeolite pellets, making CO2 molecules more difficult to become active sorbent. The addition of bentonite into zeolite 5A pellets with more compression time resulted in the reduction of specific surface area. The compression force and mass fraction of the binder were found to offer significant control over CO2 adsorption capacity. No addition of binder, 200 MPa compression force and 5 min compression time resulted in a maximum CO2 adsorption capacity of 3.64 mmol CO2/g. This research indicated that zeolite 5A pellets have a beneficial effect and high potential as an adsorbent, especially in terms of CO2 adsorption and environmental applications

The objectives of the research were to develop synthesis and estimation of each factor on carbon dioxide adsorption of advanced functional zeolite NaY material derived from bagasse ash and rice husk ash with different crystallization temperatures and weight percentages of zinc by the ion exchange method. The adsorbents were tested in a packed bed reactor at different temperatures and flow rates of carbon dioxide. The Minitab program was used to estimate the effects of each factor on carbon dioxide adsorption properties. The results showed that extracted silicon dioxide from bagasse ash and rice husk ash could be successfully used as raw material for zeolite NaY synthesis with a crystallization temperature of 298.15 K. The zeolite NaY crystalline structure was well-preserved after ion exchange. The highest capacity of carbon dioxide adsorption was at 10.33 mmol/g with zeolite 5B298-373-1. The results of the Minitab program showed that the carbon dioxide adsorption decreased with increasing crystallization temperature and carbon dioxide flow rate parameters. However, the increased weight percentage of zinc loading on zeolite NaY resulted in better carbon dioxide adsorption. The factors of the types of adsorbents and adsorption temperature showed interaction with each other.

This study focused on a quantitative study of the CO2 adsorption dynamic within the adsorbent particle. It could drive and improve ideal pore characteristics and the adsorption process efficiency. The parameters operating conditions for the CO2 adsorption process of zeolite 5A pellet were studied using Aspen Adsorption. The effects of compression force (200–400 MPa), compression time (5–15 min), and addition of bentonite binder (0–15% wt. of bentonite binder) for zeolite 5A pelletization and temperature for CO2 adsorption ranging from 298–373 K were studied. There was an error from the simulation of approximately 0.34–10.62% compared to the experimental results. The results showed that the interparticle voidage was reduced, and the appropriate mass transfer was required for good CO2 adsorption capacity. Reduction of interparticle voidage is achieved using a small compression force, a short compression duration, and a small bentonite binder, all of which significantly increase CO2 adsorption capacity. The mass transfer must be within the optimum range because it will decrease the contact time between the zeolite surface and the CO2 molecules. The CO2 adsorption increases with the gas phase temperature decrease. The result showed that the maximum CO2 adsorption by zeolite 5A was 7.078 mmol CO2/g with 0 wt% bentonite binder, 200 MPa, and 5 min at 298 K, 1 atm pressure.