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An artificial neural network (ANN) was applied to construct the relationship between the CO2 photocatalyst variables. A total of 147 data points from 38 research publications related to photocatalytic CO2 reduction via bismuth-based photocatalysts were used to develop, validate and test the developed model. The most important variable for the yield of the obtained product is irradiation time. The longer irradiation time the higher obtained product yield. Whereas the type of main product and band gap energy had the strongest effect on product yield in the positive and negative directions, respectively, in the Pearson correlation analysis. The ANN model was successfully tested to predict other literature datasets. The ANN model can then be used to estimate the yield of the obtained product, which reflects the CO2 photocatalytic reduction efficiency.

Nowadays microplastics have become a significant environmental concern, impacting both freshwater and marine ecosystems. In response to this issue, extensive research has been conducted to explore methods for separating microplastics from water. One area of investigation involves the use of computational fluid dynamics (CFD) models to study hydrocyclones and their intricate flow patterns. In this study, CFD was systematically used to examine various hydrocyclone designs with different geometrical parameters, including the ratios of cylindrical diameter to underflow diameter and overflow diameter, the cone to cylindrical height ratio, and the inlet angle. The efficiency of these hydrocyclones has been evaluated based on key performance metrics, including microplastics recovery percentage, water split percentage, and pressure drop. The results of this study have revealed noteworthy findings. Moreover, statistical analysis, specifically the analysis of variance (ANOVA), was employed to determine the significance of various geometric parameters on microplastics separation within the hydrocyclone. As a result of this comprehensive investigation, an optimized hydrocyclone design was proposed. This optimized hydrocyclone featured an underflow diameter to diameter of the cylindrical ratio of 0.264, an overflow diameter to diameter of the cylindrical ratio of 0.3, a cone to cylindrical height ratio of 13.22:70.78, and a tangential inlet. This configuration achieved a remarkable 76% microplastics recovery, a 52% water split, and a pressure drop of 82,340 Pa.

Combining biomass fuel with coal in circulating fluidized bed (CFB) boilers is attractive as the increasing of energy demand. The characteristics of biomass/coal co-firing in the industrial boiler are then investigated using computational fluid dynamics (CFD). In this study, fuels of interest are coal, wood chips, and bark. The fuel proportions were set for investigating their effects on the combustion using a simplex centroid mixture design. CFD simulations consist of a standard k-epsilon viscosity flow model, Euler multiphase fluid flow model, and a simplified biomass-char combustion reaction model. The predictive responses of the model are bed temperature, heat flux, and carbon dioxide (CO2) and carbon monoxide (CO) mass flows. The simulation results showed that the operation with coal gave the highest temperature and heat flux, followed by wood chips and bark. On the other hand, the operation with biomass releases fewer gas emissions, CO2 and CO, than those of the operation with coal. The type and proportion of boiler fuel can be easily determined using two methods: predictive equation and ternary contour plot graph, which can be likened to the digital twin of biomass/coal co-firing boiler.

In this work, the industrial-scale co-fired power plant in Thailand was analyzed and the optimization model was proposed to provide a proper fuel selection for the feedstock seasonal planning to minimize the cost of electricity generation. Also, the dust emission model was introduced in this work to investigate the environmental concern of the proposed fuel formula. The seasonal effects including feed price, properties, and availability were also included in the optimization model. The optimum solution reported a set of fuel formulas for each season that is capable of maintaining power production stability and minimizing fuel costs. Although, the global demand for coal was at its peak in the winter season, using biomass (wood chip, wood bark, and fiber) could increase the production to achieve its minimum requirement. The optimization could reduce the cost of electricity (COE) production by up to 14% (in the winter season). Also, the emission model indicated that to increase the steam production rate to meet the requirement in the summer season, a larger amount of mixed fuel consumption rate was needed. This led to an increase in dust emissions in the summer season. However, in the winter season, the result from optimization could decrease dust emissions by up to 50%. In conclusion, increasing biomass utilization is a favorable option in both economic and environmental aspects.

Polymer-based heat exchangers can offer a promising solution for environmental sustainability due to their low energy consumption. The incorporation of microchannels and nanofluids further enhances the heat transfer performance of these heat exchangersIn this study, a polymer-based microchannel heat exchanger combined with nanofluid is simulated through the integration of an artificial neural network predictive model and a three-dimensional computational fluid dynamics model. This study unveils an advanced calculation that integrates artificial intelligence and readily-available computational software provided as the advanced calculation system. A statistical mathematics response surface method which data is used for correlating the calculation model is applied to obtain the design parameters between operating conditions and for optimal performance. The optimized results reveal that polymer-based microchannel heat exchanger combined with nanofluid is a promising innovation. The heat transfer improvement achieved a 12 % increase in the overall heat transfer coefficient by using TiO2/Water compared to Water. Moreover, a 1.03 performance index is obtained when CuO/Water nanofluid is used, a 66 horizontal parallel connecting of the polymer-based microchannel heat exchanger shows that the equipment can afford the same heat transfer performance of the metal-based microchannel heat exchanger in TiO2/Water nanofluid usage and implying a balance between heat transfer enhancement and energy consumption.

Abstract Bismuth oxyhalides (BiOX) including BiOCl, BiOBr, and BiOI, were well synthesized using solvothermal technique and then used in the aqueous phase photooxidation of glycerol as a catalyst. The as-synthesized BiOBr could achieve the highest glycerol transformation of around 85.6% in 8 h under ultraviolet light (UV) irradiation among as-synthesized BiOXs. Moreover, the BiOBr/TiO2 heterojunction was also prepared through an ethylene glycol-assisted solvothermal process. This new BiOBr/TiO2 heterostructure exhibited excellent photocatalytic activity (97.4%) for the oxidation of glycerol compared with pure BiOBr (74%) under ultraviolet light irradiation at 6 h. This obtained behavior was confirmed by more produced OH• radicals of BiOBr/TiO2.

Waste heat utilization has been prioritized especially in various industries and sectors. Many researchers have developed heat recovery processes by designing suitable waste heat recovery units (WRU), such as heat exchangers, using water as a coolants to receive heat from the waste heat fluid in the production process. The conventional heat exchanger has limitations such as its equipment size, space for installation, and flexibility. The microchannel heat exchanger is one of many ideas for resolving these limitations. Moreover, the coolant on the cold side can be upgraded by adding nanometer-sized solid particles which is called “Nanofluid”. To reduce the high investigation cost and time, a new efficient and cost-effective simulation method was selected to use for investigating the performance of a microchannel heat exchanger with nanofluids in this study. To analyze the heat recovery at low temperature, i.e. around 100–200 °C, nanofluid property predictive models were developed using an artificial neural network (ANN). Then, the predictive models were embedded and integrated into computational fluid dynamics to design a microchannel heat exchanger. It is found that the use of nanofluids improved the heat transfer efficiency of this heat exchanger. The suitable nanofluid types and concentrations were selected based on the thermal–hydraulic​ performance. Here, the 3% weight TiO2/Water fluid with a 1.03 thermal–hydraulic​ performance ratio was found to be the most promising nanofluid for using in this condition.

In this study, the CaO adsorbent was prepared by using local waste eggshell as a raw material. The influence of preparation parameters including calcination temperature, calcination time and particle size of eggshell powder on the adsorption surface area were investigated. By means of statistically experiment design, the interesting parameters were investigated by a full 23 factorial design. The prepared sorbent material was characterized by X–ray diffraction (XRD), Scanning electron microscopy (SEM) and the Brunauer–Emmet–Teller (BET). The results showed the particle size of eggshell powder greatly affected the BET surface area. By applying the prepared condition of 149 μm in particle size, 6 h of calcination time and 1,000oC calcination temperature, the obtained CaO adsorbent yielded the highest in BET surface area of 5.023 m2 g-1. The CO2 performance test in the fluidized bed reactor with 12% V/V CO2 in N2 balance also revealed that the local waste eggshell can be used as CO2 adsorbent. The CO2 carrying capacity of the highest BET surface area sorbent was 0.011 g CO2 g-1 sorbent at 700°C carbonation temperature.

Air quality has a significant impact on the health of the people especially inside buildings that use closed air conditioning systems. When the indoor air quality level is below the standard but the people are unable to detect and continue to work in that area, it may affect to human health and cause respiratory disease. In this study, a carbon dioxide (CO2) sorbent based on the synthesis of potassium carbonate/gamma-alumina (K2CO3/γ-Al2O3) modified with amine-based solvents was developed. The sorbent exhaustion was indicated by observing the indicator color change for indoor direct air capture of CO2. The results showed that the modified sorbent had adsorption capacity around 60–64 mg CO2/g sorbent under room temperature and atmospheric pressure. The modified sorbent could successfully demonstrate its exhaustion by changing color of the sorbent. In addition, the exhaustion sorbents could also be reused by thermal regeneration process using conventional microwave oven due to the low power consumption and less regeneration time.

The spherical inert particles are typically added to a fluidized bed system to promote the fluidization of non-spherical particles. In this study, the mixing behavior of binary mixtures of rod-like particles and spherical particles in a bubbling fluidized bed was investigated using a computational fluid dynamics-discrete element method (CFD-DEM) simulation. The 2kfactorial experimental design was used to study the effect of particle size and rod-like particle loading on the average mixing index, as measured by the Lacey mixing index. The use of smaller spheres and rod diameters resulted in a high average mixing index despite increasing the rod weight. The effect estimates from the factorial experimental design indicated that the rod diameter was the most crucial factor for the average mixing index. Furthermore, the sphere diameter also had a significant effect. Nevertheless, the rod weight and interaction of parameters had a slight effect on the average mixing index. These findings confirmed the significance of using inert spherical particles for improving the hydrodynamics properties of non-spherical particles, including the mixing behavior of the binary mixtures system.

The aqueous-phase glycerol photocatalytic oxidation under ultraviolet irradiation was studied to reduce the fossil energy or electricity usage. Here, the glycerol is transformed into several valuable products over the new Bi2O3/TiO2 composite heterostructure which was well produced by employing maleic acid as an organic binder. The prepared α-Bi2O3/TiO2 composites revealed higher photocatalytic activity for the conversion of glycerol (88.7%) compared with TiO2 (69.7%) under ultraviolet irradiation at 8 h which could be attributed to their relative positions of the energy bands. Nevertheless, all the Bi2O3/TiO2 heterostructures had the same photocatalytic transformation of glycerol and gave similar distribution of generated valuable products. Moreover, the photocatalytic activity of the β-Bi2O3/TiO2 heterostructure had been compared to those of pure TiO2, α-Bi2O3, β-Bi2O3 and α-Bi2O3/TiO2 for the photooxidation of glycerol under the same conditions.

In multi-solid, particle-size fluidized bed reactor systems, segregation is commonly observed. When segregation occurred, small solid particles were entrained to the top of the bed and escaped from the reactor. During the combustion process, the small solid particles that escaped from the boiler were burned and subjected to damage around the cyclone separator. This study then employed a computational fluid dynamics approach to investigate solid particle behavior in the reactor using three different sizes of solid particles. The effects of baffle insertion, baffle angle, stage number, and its arrangement were examined. The percentage of segregation was calculated to compare behavior among different reactor systems. The insertion of 45-degree baffles resulted in reduced segregation behavior compared to cases without baffles and with 90-degree baffles, attributed to solid hindering and collision phenomena. Additionally, a double-stage baffle with any arrangement could reduce segregation behavior. The best arrangement was “above-arrangement” due to particles hindering, swirling, and accumulating between the baffle stages. Therefore, to diminish segregation behavior and enhance combustion chemical reactions, the insertion of baffles in the reactor zone is recommended.

An increase in power demand is one of the key reasons for the global warming problems due to the increase of greenhouse gas emissions. Carbon dioxide (CO2) is the main greenhouse gas emitted into the atmosphere. CO2 capture technology becomes an alternative solution to reduce CO2 emissions. There are many processes for CO2 capture technology. Among these, CO2 adsorption using solid sorbent has been wildly received attention. Most of the study was focused on the adsorption performance of solid sorbent. However, only a few studies were focusing on the regeneration of solid sorbent. This study investigated the effects of regeneration temperature and pressure on the regeneration rate of non-modified and modified K2CO3/γ-Al2O3 with monoethanolamine (MEA). The results showed that an increase in regeneration temperature and a decrease in regeneration pressure enhanced the regeneration rate of non-modified and modified K2CO3/γ-Al2O3. Furthermore, the experimental data of the regeneration rate was fitted to Avrami’s fractional-order model for further use in other applications.

Internally circulating fluidized bed reactor (ICFB) is the reactor that combines the conventional circulating fluidized bed (CFB) reactor system, including riser, downer, loop seal and cyclones, into a single compact reactor column. The ICFB reactor column is separated into two sections (riser and downer) by baffles and is linked together via connecting ports. The solid particles are circulated in the ICFB reactor by unequal fluidizing velocities in the riser and downer sections. The solid particles in the downer section are operated with low fluidizing velocity in the bubbling fluidization regime. In the riser section, the solid particles are transferred to the downer section because of the high fluidizing velocity. In this study, the carbon dioxide reforming or dry reforming reaction of methane was investigated. Dry reforming is a reaction between carbon dioxide and methane, which are the major greenhouse gases, for producing syngas, hydrogen and carbon monoxide. The hydrodynamics and dry reforming reaction with different reactor designs were explored using two-dimensional Eulerian–Eulerian computational fluid dynamics simulation (CFD). The ICFB reactor with no elevation gas distributor, 90 cm of draft tube height, 2 cm of loop-seal length and 1 cm of gas outlet diameter gave the highest methane conversion of 15.4%. The analysis of variance (ANOVA) indicated that the length of loop-seal and the gas outlet diameter gave substantial negative and positive effects on methane conversion, respectively. The interaction between length of loop-seal and gas outlet diameter also had a significant effect on the methane conversion. Although the ICFB reactor in this study gave the methane conversion slightly lower than referenced literature conventional CFB reactor, the ICFB reactor is the reactor that can reduce construction cost and simplify complex reactor operation.

The chemical looping hydrogen production (CLHP) process is a new approach for hydrogen (H2) fuel production. The proposed process consists of three reactors which are air reactor (AR), fuel reactor (FR) and steam reactor (SR). In this study, the gas solid flow behaviour in a cold model of the proposed CLHP process was simulated using computational fluid dynamics (CFD) with kinetic theory of granular flow. The effect of drag coefficient models on the pressure profile of each reactor was investigated and the results from the modified Syamlal–O’Brien drag model agreed well with the experimental data. The model was further used to investigate effects of the operating parameters on the hydrodynamics profiles of each reactor. The solid flux increased with the increasing of inlet velocity of AR and FR but decreased with the increasing of the inlet velocity of SR. At the same time, the solid flux increased with the increasing of the solid inventory.

In this paper, the steam production of the power plant from four biomass types has been investigated via the combination of the neural network (NN) model and constrained particle swarm optimization (CPSO) methods. First, the power plant modeling was accurately developed using NN simulation. Then, the model was applied to the optimization step, where the CPSO (the modified algorithm from the classical PSO) was introduced. The proposed method included real operation constraints to the algorithm, such as biomass feed availability and minimum steam production rate. In the optimization step, the COP has been defined as the cost function to check the present operation’s economic viability. To obtain the minimum production cost (COP), the CPSO suggested feeding wood bark from sources C and D with the amount of 104.1 and 463.8 tons/day, respectively. The result has been extensively validated by the real operation. The calculation framework in this study then applies to various production systems. Besides, by integrating the cost function in the optimization model with other indicators such as environmental impact indices, the output would provide an additional holistic picture of economic and environmental aspects.

The minimum fluidization velocity (Umf) and maximum pressure drop (ΔPmax) of a gas-solid fluidized bed are important hydrodynamic characteristics. The accurate information of these characteristics is required for obtaining the optimum design and operating conditions. In this study, a multi-layer perceptron (MLP) based on an artificial neural network was developed to accurately predict these hydrodynamic characteristics dealing with the influence of the particle size distribution (PSD). The MLP model parameters were adjusted by the backpropagation learning algorithm using wide ranges of experimental data from conducted experiments and collected literature. The five influential dimensionless groups of parameters were used for simultaneous estimation of the Umf and ΔPmax. Statistical accuracy analysis confirmed that a two-layer feedforward with thirteen hidden neurons was the best architecture for the MLP model in terms of absolute average relative deviation (AARD), mean square error (MSE) and regression coefficient (R2). The accuracy of Umf and ΔPmax was 10.36% and 8.35% with AARD, 1.7 × 10−4 and 0.0188 with MSE, and 0.9935 and 0.9152 by R2, respectively. Besides, the predictive performance of the developed model was compared with other literature models. The comparison shows the performance of the developed MLP model was acceptable.

The concern about the environment is the driving force to reduce the CO2emission. The main source of CO2 emission is from the flue gas from combustion process. The K2CO3solid sorbent in circulating fluidized bed reactor (CFB) is nominated as an efficient method for capturing CO2in flue gas. The CFB reactor consists of two reactors including circulating fluidized bed riser (CFBR) and circulating fluidized bed downer (CFBD). The study focused on the CFBR as it was used in adsorption process. However, CO2 capture capacity is limited due to the equilibrium at the specific system temperature. This study developed the computational fluid dynamics model of the nonisothermal circulating fluidized bed riser which included effect of the cooling water tube. The simulation procedure found the suitable grid number and simulation time of 420,000 cells and 100 s, respectively. The effect of cooling water temperature on the system hydrodynamics and temperature profiles was investigated. The results showed that the CO2 capture capacity increases with the decreasing temperature of cooling water temperature.

Minimum fluidization velocity is an important property which can influence the hydrodynamics and chemical conversion in fluidized bed reactor. Most of the fluidized bed boilers usually mix raw biomass solid particles with medium silica sand solid particles. This is because the biomass supply is varied with the season and location. The objective of this study is to investigate the effect of binary and ternary biomass mixtures with medium solid particles on the obtained minimum fluidization velocity. The experiment was conducted with three types of biomass including, wood chip, rice husk and palm shell waste, together with silica sand. The biomass mixtures were mixed according to the mixture experimental design. The results showed that the mixture of biomass could improve the hydrodynamics inside the system. The minimum fluidization velocity was thus decreased when conducting the experiment with the binary and ternary biomass-silica sand mixtures. The obtained minimum fluidization velocity range was 0.19 to 0.37 m/s.

At present, global warming becomes a major problem affecting the world in many ways. The main cause is the releasing of large amounts of carbon dioxide (CO2) into the atmosphere. The reduction of CO2 is thus a tremendous challenge. The CO2 capture processes then are invented to account this problem. One of the essential basic information for designing and operating of these separation processes is the adsorption–desorption equilibrium. In this study, the equilibrium isotherms on potassium carbonate on gamma-alumina (K2CO3∕γ-Al2O3) solid sorbent were correlated with Langmuir, Freundlich, Sips and Toth models. The CO2 sorption capacities were measured with pressures at different system temperatures (45–90 °C). From the result, it was found that Sips isotherm was the suitable model (R2 ranged between 0.91–0.99 with an error of less than 2.09%). When comparing the CO2 capture capacity with pure K2CO3, the obtained CO2 capture capacities were improved by impregnating K2CO3on the γ-Al2O3 support.

Carbon dioxide (CO2) has been increasingly released to the environment with the increased electricity demand via fossil fuel combustion. The alternative solution is the combustion unit that prevents CO2 from releasing. Chemical looping combustion is the combustion unit that can achieve this objective and provides high purity of a CO2 product for meaningful uses. The high efficiency of the process is achieved by designing good reactor hydrodynamics. A dual circulating fluidized bed reactor was then investigated in this study. The two parameters were studied; the temperature of the reactor (A) and the ratio of coal velocity to the weight of oxygen carrier (B). The two responses were analyzed; 1) combustible gas percentage from a fuel reactor, and 2) CO2 percentage from an air reactor. The 3kfactorial experimental was used for systematic experimental design which included the curvature behavior of the result. The results indicated that parameters A and B affected the combustible gas percentage from the fuel reactor. However, only B affected the CO2 percentage from the air reactor. The high A and B gave a high combustible gas percentage from the fuel reactor and high CO2 percentage from the air reactor. The high combustible gas percentage from the fuel reactor indicated the incomplete combustion and the high CO2 percentage from the air reactor indicated the high CO2 releasing to the environment. The low values of A and B then supported the proper hydrodynamics in these reactors which will provide the efficiency of fuel usage, the reduction of CO2 emission to the environment, and the mitigation of the environmental crisis.

The objective of this study was to develop empirical models for predicting the obtained products from lignocellulosic biomass through alternative technologies. The model can be applied for further studies to provide the insight information for bio-refinery optimization and planning where suitable biomass characteristics are necessary for the conversion pathways to achieve the target products. To build the regression model, 330 case studies including the use of 66 lignocellulosic biomasses in 5 technologies were simulated using Aspen plus 11.0 software. Five correlations between biomass characteristics and five product yields were then successfully developed with R2 equals to 0.99. The results indicated that almond shell with high VM, C, H contents and low FC, O, N contents produced the highest syngas, hydrogen, power and liquid fuels product yields (7121 kJ/kgbiomass, 0.051 kg/kgbiomass, 6474 kJ/kgbiomassand 0.12 L/kgbiomass, respectively). Among the local biomass candidates, palm empty fruit bunch (PEFB) was the preferable choice.

Nowadays, the concentration of greenhouse gases in the atmosphere has been growing continuously due to the increase of energy consumption, generated from carbon-based fuels and has created global warming. In this study, a model of carbon dioxide capture adsorption in a fluidized bed reactor was developed based on experimental data using commercial CFD program called ANSYS FLUENT. Then the model was employed to observe the hydrodynamics behavior and the dynamic responses of CO2 capture inside the adsorber when the operating variables were changed. The effects of operating variables on carbon dioxide capture were evaluated. From the simulation results, both the inlet gas velocity and the inlet solid circulation rate affected the carbon dioxide capture. The relationships between inlet gas velocity and inlet solid circulation rate to the percentage of carbon dioxide capture were investigated and analyzed by using system identification toolbox in MATLAB. After that, these relationships were used to design a control system. For the considered control system, the inlet solid circulation rate was selected to be a manipulated variable, while the inlet gas velocity, composition and temperature were designated as system disturbances. The controlled variable was carbon dioxide content remaining in the flue gas at the outlet. It was found that the control system could maintain the concentration of carbon dioxide in the flue gas at a specified value. Keywords: Carbon dioxide capture, Fluidized bed reactor, Solid sorbent, CFD, Adsorption, Control system

Nowadays, the global warming is considered as a world problem because it influences the environment by increasing the average temperature of earth surface. One of the greenhouse gases that release from human activities and fossil fuels combustion in industry is CO2. Several technologies are applied to reduce the CO2 emission to atmosphere. In this study, the aim is to capture the CO2 by solid sorbent adsorption with potassium carbonate supported on gamma alumina using full loop circulating fluidized bed reactor in commercial computational fluid dynamics program, ANSYS FLUENT. This study focuses on the effect of initial CO2 concentrations from cement industry and power plant on CO2 removal efficiency. Besides, the solid volume fraction profile is also considered. The simulation results showed the hydrodynamics in circulating fluidized bed reactor that the solid sorbent was high at the reactor wall and low at the reactor center. In addition, the independent input variables were investigated which were percentage of K2CO3 loading on sorbent and gas velocity. The increasing of K2CO3 loading on sorbent and the decreasing of gas velocity increased the CO2 capture efficiency. Keywords: Circulating fluidized bed reactor, K2CO3 sorbent, CO2 capture, CFD, Cement

Chemical looping combustion (CLC) is a technique for separating carbon dioxide from flue gas. It consists of two main processes: a fuel reactor and an air reactor. In the fuel reactor, fuel reacts with solid metal oxide particles to produce heat, CO2 and H2O vapor which later can be easily separated by the condensation. The reacted solid metal is then sent to the air reactor for regenerating via an oxidation reaction with air before being returned to the fuel reactor. In this study, these reactors in the CLC system are integrated as a circulating fluidized bed system and a dynamic model has been developed for the system. The fuel reactor (or downer) operates in bubbling fluidization regime where the air reactor (or riser) operates in fast fluidization regime. Using the developed dynamic model, the transient responses of various control variables such as the temperature of two fluidized bed reactors, pressure and the liquid level of a condenser have been controlled by manipulating variables such as heat transfer rates of the reactors, gas outlet flow rate and liquid outlet flow rate of the condenser. A proportional–integral–derivative (PID) controller was tuned for controlling purpose. The integral of the absolute value of error (IAE) is used to evaluate the control system performance. Keywords: Chemical looping combustion, Fluidized bed reactors, Aspen Dynamics, Dynamic simulation

Carbon dioxide adsorbent is an important factor in the adsorption process of carbon dioxide. Therefore, this study interested in the adsorption of potassium carbonate solid sorbents on gamma-alumina to adsorb carbon dioxide. The added basic solution was used instead of the de-ionized water by assuming that it would give higher support surface area. The various preparation parameters were explored by impregnation method as follows: the different base types (NaOH, Ca(OH)2, and Na2CO3), the basicity of the solution (8, 10 and 12) and the duration of shaking (12, 18 and 24 h). From the results, all parameters affected on the carbon dioxide capture capacity. The sodium hydroxide gave the highest carbon dioxide capture capacity. An increasing in basicity of the solution resulted in higher carbon dioxide capture capacities, since the reactant was acidic. For the effect of the time spent on shaking the adsorbent, the ability to capture carbon dioxide increased with preparation time. The highest adsorption capacity of 4.34 mmol CO2 / g sorbent was obtained from potassium carbonate adsorbent, prepared by using sodium hydroxide with a pH value of 12 and a duration of 24 h while, in normal preparation condition, potassium carbonate adsorbent had a capacity of 2.27 mmol CO2 / g sorbent. Keywords: CO2 capture capacity, Impregnation, Base condition, K2CO3/Al2O3