Complete Factorial Design Research Articles

Factorial design methodology for synthesizing zeolites: A critical review

AbstractThis review shows an outlook about several works which have used the factorial design methodology for synthesizing zeolites and mesoporous materials, included the use of wastes as sources of silicon and aluminum. In the bibliography several interesting works were identified with a complete development of the factorial design methodology. However, there are other works that showed a limited statistical analysis of the results. In spite of these issues, their contribution in the advance of synthesis of zeolites is important. Moreover, different ways to measure the crystallinity were detected being the X‐ray diffraction (XRD) the most used technique. This work also gives a proposal of the complete factorial design methodology as a guide in future works for synthesizing zeolites or zeo‐types materials. This work presents a detailed review of the methodology of designing experiments for the synthesis of zeolite or zeo‐type materials, where it has been shown and analyzed the type of design used, because the choice of a design involves a large number of experiments or few experiments thus facilitating the production of zeolite, in addition to the factors that influence the synthesis give information of the type to obtained zeolites, also includes a guide for applying this methodology. Experiment design methodology can help to produce high quality zeolites from virgin raw material or waste that impact the economy of the zeolite industry.

Comparing how compost and manure affect soil organic matter using a complete factorial design

BackgroundThe aim of this study was to determine the influence of physico-chemical factors on soil organic matter by comparing two types of soil improver: one produced from olive mill waste cake residues (CRPM) and the other from manure (CF). This was achieved using Full Factorial Design, the main objective of which is to measure precisely the impact of each factor on a given response, to analyze the interactions between the various factors and to identify the optimum conditions for achieving a specific objective or improving the performance of a process. MethodsFour independent factors were studied: pH, electrical conductivity, humidity and carbon/nitrogen (C/N) ratio. Using design, based on their significance, coefficient of determination, analysis of variance and Pareto charts, the interactions between these variables were assessed to identify those with the most positive impact on soil fertility. ResultsThe results show that, for CRPM compost, the most positive interaction is between pH and ratio C/N. For manure, the interaction between pH and moisture has the greatest beneficial effect. These findings underline the importance of controlling all three factors − pH, moisture and ratio C/N to optimize soil fertility. ConclusionsThe analysis confirmed the reliability of the models used, with p-values below 0.05 and coefficients of determination (R2 and adjusted R2) close to 1, indicating the robustness of the models. Pareto diagrams were used to precisely identify the most relevant interactions for improving soil amendment management.

Effect of the Digestibility of Cassava Flour (Manihot esculenta Crantz) by Enzymes Extracted from Corn Malt.

The aim of this study is to determine the effect of the digestibility of cassava starch by the enzymes extracted from corn malt, which will constitute one of the answers to the problem of integrating local products into the process in a modern brewery. Cassava starch solutions of different concentrations (E0: 0g/L; E1: 1g/L; E2: 1.1g/L; E3: 1.2g/L; E4: 1.3g/L; E5: 1.4g/L and E6: 1.5g/L) were prepared and subjected to two treatments (gelatinized and non-gelatinized) and 5mL of each were placed in a test tube. Three millilitres (3mL) of the solution containing amylases extracted from malt corn was then added to each of the test tubes containing the cassava flour solutions. All the treatments were subjected to three temperature stages (50°C for 15min, 90°C for 20min, and 100°C for 75min). Twenty-eight (28) objects (two duplicates) were experimented in a complete factorial design (2 treatments × 2 temperature levels). The results obtained showed that gelatinization had no effect, which could be due to the high optimum temperatures of corn enzyme activity. The concentrations also did not have significant differences which shows that these concentrations can well be used on an industrial scale to digest cassava starch by corn malt enzymes.

Structural, physicochemical and technofunctional properties of corn gluten meal modified by extrusion

This study aimed to evaluate the influence of sample moisture, extrusion temperature, and extruder screw speed on the hydration properties of corn gluten meal (CG), optimize process condition for the highest protein solubility at pH 7 (PS7) and WAC, and assess the effect of the optimized extrusion process on the structural, chemical, physical, and technofunctional properties of CG proteins. Extrusion was carried out at different sample moisture (20%–40%), temperatures (120–160 °C), and screw speeds (33–117 rpm) using a complete factorial design with two central points. All extrusion conditions resulted in reduced hydration properties. Extrusion with 20% sample moisture, 120 °C and 117 rpm resulted in the lowest loss of water absorption capacity and protein solubility at pH 7 (optimized condition). After optimized extrusion, the GC became darker and showed greater activity and protein emulsifying capacity and lower foaming capacity. Furthermore, CG proteins had reduced solubility at different pHs. Changes in technofunctional properties resulted from changes in protein structure after extrusion. The new protein structure is stabilized by non-covalent bonds (hydrogen bonds and hydrophobic interactions) and disulfide bonds. Extruded corn gluten has the potential to be used as an ingredient in bakery, emulsified meat products, salad dressings, vegetable pates, and desserts.

Ultraviolet‐B Stress Increases Epidermal UV‐Screening Effectiveness and Alters Growth and Cell‐Wall Constituents of the Brown Midrib bmr6 and bmr12 Mutants of Sorghum bicolor

ABSTRACTThe brown midrib bmr6 and bmr12 mutants of sorghum (Sorghum bicolor) have alterations to the phenylpropanoid pathway impairing the activity of cinnamyl alcohol dehydrogenase (CAD) and/or caffeate5/hydroxyferulate O‐methyl transferase (COMT) enzymes, which inhibit lignin synthesis. Interestingly, these phenylpropanoids can also act as sunscreen compounds in plants and potentially attenuate ultraviolet radiation. We examined the effects of ultraviolet‐B (UV‐B; 280–320 nm) exclusion on growth, cell‐wall constituents and UV‐screening abilities of bmr6, bmr12, a double mutant (bmr6 bmr12; dm) and wild‐type (WT) genotypes of S. bicolor. Plants were grown in a UV‐transparent greenhouse under filters that either transmitted 2.8% (Mylar) or 90% (Aclar) of UV‐B. The greenhouse experiment was a 2 × 4 (UV treatment × genotype) complete factorial design. Sorghum grown under reduced UV were 23% taller and had 22% fewer leaves. Among genotypes, the WT plants were 5%–12% taller than the bmr6, bmr12 and dm mutants. The near‐ambient UV‐B treatment group was more effective at UV screening and had a 16% higher UV‐screening effectiveness than those under reduced UV‐B. Sorghum plants with the bmr6 and dm genotypes had 8%–19% higher UV‐shield than the bmr12 and WT. Plants grown under the reduced UV‐B treatment had 5% less hemicellulose and 6% more cellulose in their cell walls. There were no overall treatment effects on bulk soluble phenolics, chlorophyll fluorescence (Fv/Fm) or lignin concentrations. These results are a possible indication that the bmr mutants of S. bicolor have a varied response to UV‐B exclusion due to alterations in the phenylpropanoid pathway leading to redistribution of metabolites.

Modeling of mechanical behavior of Agave sisalana fiber's yarn using the design of experiments method

The aim of this study is to propose a model for predicting the mechanical properties of natural sisal yarn based on mechanical strength of used fibers, unit twist of yarn and its density. To achieve this, a complete factorial design modelling method was used, based on a design of experiments approach, which is recommended today because of the ease it offers in taking into account the most complex phenomena. It was developed on the basis of laboratory tests. The model obtained predicts mechanical strength and elasticity modulus of sisal yarn, based on control parameters such as fiber strength, unit twist and yarn mass. This model is currently one of the most accurate tools for predicting and optimising the mechanical properties of sisal yarns. The iso-surface curves represented by this model, can be used to obtain the strength and elasticity modulus of sisal yarn during manufacture, by varying the optimum control parameters. This model is an original tool that can be recommended to the spinning and sisal fiber composite manufacturing industries and others, as it saves time and materials and ensures precision in the manufacture of yarns according to the field of application, thereby contributing to safety in use.

The effect of shade and drought on the growth and proline content of Medinilla speciosa and Medinilla verrucosa plants

Abstract Medinilla is a cultivated wild plant because it has medicinal properties. This research aims to determine the level of resistance and growth of Medinilla speciosa and Medinilla verrucosa plants in drought and shade conditions. The research was carried out in April 2022 – April 2023 in Pakem District Sleman Regency. Analysis of proline and chlorophyll content was carried out at the Gadjah Mada University Laboratory. This study used a nested complete factorial randomized block design, with the types of Medinilla speciosa, Medinilla verrucosa and the volume of water given, 1750 ml, 1500 ml, 1250 ml per polybag nested in 25%, 50% and 75% shade. Each treatment was repeated three times, resulting in a total sample of 54 plants. The results of the study showed that the volume of water provided in the shade suppressed growth, that is number of leaves, leaf area, root volume, fresh weight of stover, chlorophyll except plant height, dry weight of stover and proline content. Water is one of the essential factors needed by plants to grow and develop well. Appropriate light intensity impacts plant growth and production. Light intensity stress and water supply volume stress are part of abiotic stress that can affect growth morphology productivity.

Use of metakaolin with a low surface area and rich in quartz and iron as a precursor in the production of structural alkali-activated concrete

Pumpable and machineable alkali-activated structural concretes are made using low-reactivity metakaolin with high quartz and iron contents. The effects and interaction of alkaline concentration (NaOH - 8, 10, 12, 14, and 16 M) and ratio of alkaline reagents (Na2SiO3/NaOH - 1.0, 1.5, 2.0, 2.5, and 3.0) on their properties were accessed using 2k complete factorial design. Higher concentrations of alkaline solutions resulted in faster hardening, decreased material deformation, and increased mechanical strength, with higher elastic modulus, lower damping, lower water absorption, and porosity. With time, the elastic modulus increased, and the dynamic damping decreased, suggesting the homogeneous formation of alkaline-activated products, confirming the proper configuration of the hardening process. The factorial design allowed for determining the ideal dosage for producing the material, indicating that the alkaline concentration (NaOH) should be 10 M and the Na2SiO3/NaOH ratio should be 2.5. They analyzed the possible combinations that allowed obtaining a material with adequate characteristics for the structural application.

Characterization and production hydroponic fodder for corn (Zea mays) and sorgum (Sorghum bicolor) at different harvest times

The study aimed to determine the characterization and production of hydroponic fodder corn (Zea mays) and sorghum (Sorghum bicolor) at different harvest ages. The study used a randomized complete factorial design. The first factor was plant type (corn and sorghum) and the second factor was harvest age (7 days, 10 days and 13 days). Each treatment was replicated 3 times. Variables observed included number of leaves, the growth rate of fodder plants, the fresh production of fodder plants, and the dry matter production of fodder plants. The research stages included seed preparation, planting, maintenance and harvesting. Data were analyzed using ANOVA and further test using Duncan’s Multiple Range Test. The results of the research show that corn is better used as fodder compared to sorghum, because corn fodder has a greater number of leaves, the growth speed is faster, the production of fresh and dry matter is also higher compared to sorghum fodder. A harvest time of 10 days relatively produces higher production and a shorter time compared to a harvest time of 13 days. The conclusion of this research is that the best growth and biomass production results is corn fodder crops with a harvest time of 10 days.

Internally cooled tools as an innovative solution for sustainable machining: Temperature investigation using Inconel 718 superalloy

Machining is a process that involves intense heat generation at localized points within the tool-chip interface. This leads to elevated temperatures, which can be detrimental to cutting tools. This issue becomes even more crucial when dealing with superalloys like Inconel 718, as they exhibit high shear strength and good creep resistance. Consequently, a significant amount of energy is expended, increasing the cutting temperature. Until now, the primary technique employed to address this issue has been using Cutting Fluids (CFs). In machining, a portion of costs is attributed to fluid handling. It also contains harmful elements that can pose health risks, potentially leading to conditions such as cancer. Moreover, the toxic components can contribute to environmental degradation when improperly disposed of. Therefore, this study proposes an innovative cooling technique called Internally Cooled Tools (ICTs). The ICTs employ an internally circulating coolant fluid through closed cooling channels within the cutting tools, eliminating fluid dispersion into the atmosphere. The main objective was to compare the performance of ICTs in controlling the tool-chip interface temperature during Inconel 718 turning using hard metal tools. For this purpose, a complete factorial experimental design (25) was utilized, with the response variable being the temperature measured by the tool-work thermocouples technique. Beyond that, a sustainable assessment was performed using the Pugh Matrix method. Many key sustainable factors were evaluated related to three atmospheres, cutting fluids in abundance – CFA, dry machining, and ICT. The data base used was a depth literature investigation together with results found in this work. The main findings of this entire work demonstrated that an increase in cutting parameters corresponded to an increase in temperature, as anticipated. TiNAl coating reduced the temperature by up to 10% compared to uncoated tools. Similarly, applying ICTs led to temperature reductions of up to 17% compared to dry machining conditions. The Pugh Matrix made considering 12 factors showed that ICT (14 points) was the most sustainable lubri-cooling method in comparison to CFA (3) and DM (5). Ultimately, ICTs showed to be a promising eco-friendly method. It outperformed conventional methods, showcasing a remarkable heat dissipation capacity. As a result, further studies are warranted to delve deeper into this promising approach.

Optimization of synthesis parameters of PUF/ENB microcapsules for self‐healing applications using factorial design methodology

AbstractThis study introduces a systematic experimental approach aimed at enhancing the production process of poly(urea‐formaldehyde) (PUF) microcapsules filled with 5‐ethylidene‐2‐norbonene (ENB) using in situ emulsion polymerization. Essential parameters were identified through a prior Plackett Burman (PB) design, leading to the implementation of a 24‐1 fractional factorial design. The key parameters selected encompassed stirring speed, poly(ethylene‐alt‐maleic anhydride) (EMA) emulsifier content, pH of the reaction, and the quantity of 1‐octanol. Optimal conditions for polymeric microcapsule synthesis were determined using a statistical analysis of the complete factorial design, facilitating the development of representative mathematical models for the process. A comprehensive evaluation of response variables including microcapsule diameter, yield, encapsulated content, stability, and thermal degradation was conducted. Utilizing response surface analysis (RSM), it was determined that the PUF/ENB(2C) condition (stirring at 700 rpm, a reaction pH of 3.0, and EMA content of 0.425 g) resides within the optimized synthesis region, producing microcapsules exhibiting favorable morphological characteristics, yield of 52% and encapsulated content of 80%.

Enhancing Sustainable Waste Management Using Biochar: Mitigating the Inhibitory of Food Waste Compost from Methane Fermentation Residue on Komatsuna (Brassica rapa) Yield

Methane fermentation, utilizing food waste (FW), is viewed as a sustainable strategy that leverages garbage and agricultural waste to conserve the environment. However, FW compost encounters growth inhibition issues, which we examine in this study. The aim of this study was to assess the influence of various compost mixtures on seed germination growth and the yield of Komatsuna (Brassica rapa). The experiment employed FW compost mixtures with biochar (BC), clay (CL), weeds (WD), and a control group in a completely randomized design with three replications to monitor germination. The experimental pots, arranged in a complete factorial design, involved three treatment factors: compost type (FW or HM), biochar presence or absence (WB or NB), and three input rates (25 g pot−1, 50 g pot−1, and 100 g pot−1), each in triplicate. The combination of FW and BC exhibited an enhanced germination rate compared to FW alone. Moreover, the inclusion of biochar significantly amplified this effect, particularly at the input rate of 50 g pot−1 and had a substantial impact on the interaction between input rate, compost type, and biochar on variables such as nitrogen (N) uptake, % N, soil carbon, and yield. Homemade BC demonstrates an increasing fertilizer cost performance (FCP) as the input rate rises across all fertilizer combinations, while commercially priced BC exhibits a reverse relationship with FCP. These findings suggest that the addition of biochar enhances the performance of methane fermentation residue compost, thereby promoting plant growth through the processing of environmentally sustainable waste.

Microstructure, hardness, and tribological performance of D2 tool steel fabricated by laser cladding using pulsed wave and substrate heating

D2 steel is a tool grade steel that presents hot cracking problems during the solidification process due to its alloying elements. On the other hand, additive manufacturing processes have great potential to manufacture, repair, and functionalize metal parts due to their low heat input, minimal distortion, and excellent metallurgical bonding. In this work, D2 metallic powder was deposited by the laser cladding process using pulsed wave, without and with preheating of the substrate. Through ANOVA statistical analysis using a complete factorial design 24, the optimal regions were determined to obtain D2 deposits with minimum dilution and depth, and maximum widths, heights and high hardness. Once the optimal parameters of the process were established, the coatings were deposited without and with preheating the substrate where, regardless of the condition, coatings without defects and good metallurgical adhesion were obtained. Coatings with preheating obtained higher cooling rates, where lower laser powers promoted higher rates; while in the coatings without preheating, lower duty functions promoted higher rates. The austenite, martensite and M7C3 eutectic carbides phases were obtained, with austenite being the main phase due to the C content in solid solution due to the cooling rates achieved. The coatings in as-built condition, reached hardness values between 606 and 711 HV (55–60 HRC), where the preheated coatings obtained the highest values. On the contrary, the coatings without preheating showed a better wear resistance (7.672 x10-6 mm3/Nm) due to the formation of tribo-layers due to the formation of oxides due to the higher amount of austenite.

Controlling Clostridium sporogenes spoilage of “requeijão cremoso” processed cheese: Modeling the growth/no-growth probability as a function of pH, sodium chloride and nisin

Predictive models were developed to assess the growth response of Clostridium sporogenes in “requeijão cremoso” processed cheese, as affected by pH and sodium chloride and nisin concentrations. A complete factorial design was performed using different formulations: pH (5.2, 5.6, and 6.0), sodium chloride (0.5, 0.75, 1.0, 1.25, and 1.5%), and nisin (0.0, 5.0, 7.5, 10.0 and 12.5 mg/kg), totalizing 75 conditions. Packs with 150 g of “requeijão cremoso” were inoculated with 103 spores/g following storage at 10 °C for up to 60 days. The counts of C. sporogenes were performed on day zero and at the end of storage after a heat shock (80 °C for 12 min). The formulations that allowed an increase in the population >1 log CFU/g were assigned the value of 1 (growth), and the formulations in which the increase was <l log CFU/g were assigned 0 (no growth). Overall, the growth of C. sporogenes was affected by pH, salt concentration and nisin, e.g. at pH 5.2 the growth/no growth limit is 1.25% salt and no nisin, at pH 5.6 this limit is reduced to 0.75% salt, while at pH 6.0 only the effect of pH was sufficient to inhibit C. sporogenes even in the absence of salt and nisin. All isolated parameters and their combinations significantly affected spore germination, indicating that the model generated significantly contributes to the optimization of the processing and mitigation of the microbiological spoilage of “requeijão cremoso” processed cheese by Clostridia.

Experimental Design of the Interaction Effect of Independent Variables on Pineapple (Ananas comosus) Fruit Bromelain Activity

Background: Certain factors are known to influence the rate of enzyme activity. It is paramount to study such independent factors to obtain the ideal conditions required to maximize enzyme activity. The time-consuming traditional one-factor-at-a-time (OFAT) approach of evaluating the effect of independent variables on enzyme activity does not consider the interaction effects of the independent variables on dependent responses. Methods: The impact of four independent variables on fruit bromelain activity was evaluated using the complete factorial design of the experiment approach. Results: The highest actual fruit bromelain activity (76.83 U/ml) and predicted activity (74.81 U/ml) were recorded at an optimum pH of 7.5, temperature of 50oC, and incubation period of 10 minutes using azocasein substrate. All tested variables except temperature; the interaction between substrate type and incubation time significantly affected fruit bromelain activity (p &lt; 0.05). Conclusion: The design model analysed the main and interaction effect of the variables on bromelain activity. Therefore, complete factorial design is a better approach than OFAT to determine the effect of independent variables on fruit bromelain activity.

Physicochemical quality of duck meat marinated using Keranji (Dialium indium) and mini vacuum tumbler

A sustainable green economy in meat production must consider food safety principles, prevent the risk of meat contamination and improve meat quality. Duck meat has a darker colour than chicken meat, a distinctive aroma, tough texture and high fat, making it less preferred by consumers. This study aimed to determine the effect of Keranji marination using a mini vacuum tumbler on duck meat. This study used a complete factorial randomised design with four replicates. Factor I was the concentration of Keranji (D0=0%, D1=10%, D2=20% and D3=30%). Factor II is marination time using a mini vacuum tumbler (V1=15 minutes and V2=30 minutes). The results showed that Keranji concentration and marination time using a mini vacuum tumbler very significantly affected (P<0.01) pH, tenderness, cooking loss, moisture content and colour. The interaction between Keranji concentration and marination time using a mini vacuum tumbler significantly affects (<0.05) pH, cooking weight loss and tenderness. It was concluded that the best result was the best for Keranji with 20% concentration and marination time using a mini vacuum tumbler of 30 minutes. Keranji is recommended as a marinade that can sustainably improve the physicochemical quality of meat.

Prediction of quality characteristics of micro-channels by deep learning algorithm during laser transmission ablation of PMMA

Underwater laser transmission micro-channelling of thick transparent polymethyl methacrylate (PMMA) using a neodymium-doped yttrium aluminium garnet (Nd: YAG) laser is the focus of this study. Experiments are conducted to determine the effect of three significant variables, namely pulse frequency, lamp current, and cutting speed, on heat-affected zone (HAZ) width, cut depth, and kerf width. Experiments are designed systematically utilising the full factorial design method. The purpose of constructing empirical models, specifically non-linear ones, is to establish and clarify the relationship between control factors and corresponding responses. A feed forward backpropagation neural network (FF-BPNN) is employed for predicting the measured response. Additionally, an assessment is made between the FF-BPNN results and the values predicted by the model. On the basis of the anticipated results, it can be concluded that the FF-BPNN model is preferable in predicting both the depth of cut and kerf width. In contrast, when specifically contemplating the measurement of HAZ width, the application of a non-linear model is more advantageous. As a measure of accuracy, the mean absolute error is computed for both the feedforward backpropagation neural network (FF-BPNN) and the nonlinear modelling technique.

Effectiveness of Bacillus subtilis ANT01 and Rhizobium sp. 11B on the control of fusarium wilt in pineapple (Ananas comosus).

Pineapple (Ananas comosus) is commonly infected by Fusarium oxysporum, causal agent of the fusarium wilt disease. Conventionally, growers use synthetic fungicides to control the disease, which lead to environmental pollution, hazardous effects on non-target organisms and risks on human health. The aim of this work was to assess the effectiveness of Bacillus subtilis ANT01 and Rhizobium sp. 11B to control fusarium wilt on pineapple plants. Four treatments derived from a complete factorial design were tested under field conditions. Treatments composed of B. subtilis ANT01 and the combination B. subtilis ANT01-Rhizobium sp. 11B decreased disease severity by 94.4% and 86.1%, respectively. On the other hand, the treatment prepared with Rhizobium sp. 11B alone showed a reduction of 75.0%. Size of leaves and nutritional condition (SPAD units) of the biocontrol agents-treated plants showed no statistical differences. Moreover, B. subtilis ANT01 decreased by 46% the initial soil population of F. oxysporum, while Rhizobium sp. 11B, B. subtilis ANT01 plus Rhizobium sp. 11B and control, showed a population reduction of 12.5%, 24.2% and 23.0%, respectively. These results make evident the potential of B. subtilis ANT01 as biocontrol agent of the pathogen under field conditions.

Utilizing Organic Compounds and Planting Medium to Enhance the Growth Rate of Vanda tricolor

This study aims to investigate the reciprocal impact of Vitamin B1 and rice washing water usage, as well as the utilization of lumber + coconut husk + moss medium, to identify the most effective medium for expediting the growth of Vanda tricolor seedlings after acclimatization, as well as determining the optimal application method for Vitamin B1 or rice washing water to enhance their growth. This study is a field experiment that uses a complete factorial randomized block design, comprising 2 elements. The primary determinant is the medium composition, consisting of either lumber or a combination of lumber, coconut husk, and moss. The secondary component is the nutrient source, which can be water, vitamin B1, or rice- washing water. The research findings indicate that the growth of Vanda tricolor after acclimatization is influenced by both the kind of medium and nutritional source, specifically to disease attack parameters. Lumber is the preferred medium for promoting the growth of Vanda tricolor after it has adapted to the conditions on the slopes of Mount Merapi. Vitamin B1 is the suggested nutritional supply to enhance the growth of Vanda tricolor after it has adapted to the conditions on the slopes of Mount Merapi.

Application of Activated Carbon from Cocoa Pod Husk (Theobroma cacao L.) in Used Cooking Oil

One method for purifying used cooking oil is to utilize activated carbon derived from cocoa pod husk. Cocoa pod husk contains high cellulose, allowing it to be an absorbent material that can reduce moisture content, free fatty acids, and peroxide value in used cooking oil. This study aims to (1) determine the effect of concentration and adsorption time of cocoa pod husk activated carbon on moisture content, free fatty acids, and peroxide value of used cooking oil and (2) determine the best concentration and adsorption time of cocoa pod husk activated carbon. This study used a randomized complete factorial design consisting of two factors: concentration of cocoa pod husk activated carbon: 5%, 10%, and 15% and adsorption time: 30, 60, 90, and 120 minutes. The results after refining using cocoa pod husk activated carbon, the moisture content dropped to 0.07%-0.28%, free fatty acid content dropped to 0.79%-1.42%, and peroxide value dropped to 32.20-32.53meq/kg. The best treatment obtained was a concentration of 15% of cocoa husk activated carbon with an adsorption time of 120 minutes, which produced used cooking oil with a moisture content of 0.08%, free fatty acids of 0.79%, and peroxide value of 32.20meq/kg.