Wongpromrat, Patthranit

Preferred name

Main Affiliation

School of Engineering

patthranit.wo@kmitl.ac.th

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Simultaneous extraction of crude polysaccharides, soluble proteins, gingerols, and shogaols from dried ginger by subcritical water extraction
(2025-06-01)
Sakdasri, Winatta
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Kaomaneechot, Sunanta
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Lasim, Sarida
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Somboon, Pichayada
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Chotigavin, Natthaporn
Subcritical water extraction (SWE) is a remarkable method for the simultaneous extraction of high- and low-polarity bioactive compounds from ginger. This study investigated the effects of temperature, pressure, and extraction time on the crude polysaccharide yield, protein content, total phenolic content (TPC), and amounts of 6-gingerol and 6-shogaol. The pressure was maintained at 30 bars, and the temperature and extraction time were optimized to maximize the polysaccharide yield, protein, TPC, gingerols, and shogaols contents. The rising temperatures (100–160 °C) and extended extraction times (10–50 min) enhanced the yield and TPC but negatively affected protein stability, leading to thermal degradation when the temperature surpassed 180 °C. Specifically, the content of 6-gingerol decreased at high temperatures because of its conversion into 6-shogaol. The optimal extraction conditions were 160 °C for 40 min at 30 bars, resulting in a polysaccharide yield of 8.54 %, protein content of 100.35 mg body surface area/g dry mass, TPC of 18.10 mg Galic acid (GA)/g dry mass, 6-gingerol content of 2.14 mg/g dry mass, and 6-shogaol content of 0.28 mg/g dry mass. Therefore, SWE effectively extracts various polar bioactive compounds from plant materials in a single step.
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Novel method for predicting the cracks of oxide scales during high temperature oxidation of metals and alloys by using machine learning
(2025-12-01)
Chawuthai, Rathachai
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Promchan, Teeratat
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Rojsanga, Jularak
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Chandra-ambhorn, Somrerk
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Nilsonthi, Thanasak
Material degradation is one of the main problems in various high-temperature processes, directly resulting in the failure of the material. Crack and protective oxide film spallation caused either by mechanical stress development in the oxidation process or thermal stress due to a mismatch of the thermal expansions of the formed oxide and alloy are common forms of failure in high-temperature processes. Typically, the Pilling-Bedworth ratio (PBR) is employed to predict crack and spallation of the oxide by determining the volume changes of oxide and alloy because of its simplicity. However, this approach provides poor crack and spallation predictions. Hence, machine learning was adopted in the present work to predict oxide formation and spallation in the temperature range of 600-1,200 °C. The inputs for the present developed model were alloy compositions, oxide formed during oxidation, and oxidation conditions and periods. Furthermore, the predicted results of the present developed machine learning model were compared to those obtained by the PBR method. The present results revealed that the accuracy of the oxide spallation prediction of the present model was better than that of the PBR method. The random forest with 15 estimators was the best machine learning model. Finally, it can be concluded that the machine learning model is essential for accurate material failure prediction.
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Classification of saline water for irrigated agriculture using near infrared spectroscopy coupled with pattern recognition techniques
(2019-09-24)
Lapcharoensuk, Ravipat
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Phuphanutada, Jirawat
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Wongpromrat, Patthranit
This research aimed to create near infrared (NIR) spectroscopy models for the classification of saline water with a pattern recognition technique. A total of 112 water samples were collected from the Tha Chin river basin in Thailand. Water samples with salinity less than 0.2 g/l were identified as suitable for agriculture, while water samples with salinity higher than 0.2 g/l were found to be unsuitable. The NIR spectra of water samples were recorded using a Fourier transform (FT) NIR spectrometer in the wavenumber of 12,500-4,000 cm-1. The salinity of each water sample was analysed by electrical conductivity meter. Identification models were established with 5 supervised pattern recognition techniques including k-nearest neighbour (k-NN), support vector machine (SVM), artificial neural network (ANN), soft independent modelling of class analogies (SIMCA), and partial least squares-discriminant analysis (PLS-DA). The performance of the NIR model was carried out with a split-test method. About 80% of spectra (90 spectra) were randomly selected to develop the classification models. After model development, the NIR spectroscopy models were used to classify the categories of the remaining samples (22 samples). The ANN model showed the highest performance for classifying saline water with precision, recall, F-measure and accuracy of 84.6%, 100.0%, 91.7% and 90.9%, respectively. Other techniques presented satisfactory classification results with accuracy greater than 68.2%. This point indicated that NIR spectroscopy coupled with the pattern recognition technique could be applied to classify saline water for agricultural use according to salinity level in natural resources.
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Possibility of metallic cobalt formation in the oxide scale during high-temperature oxidation of Co-27Cr-6Mo alloy in air
(2023-01-01)
Wongpromrat, Patthranit
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Tunthawiroon, Phacharaphon
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Bumrungthaichaichan, Eakarach
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Ponpo, Phisan
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Nilsonthi, Thanasak
Co-based alloys are known to be high oxidation-resistant material and used in several high temperature applications. During high temperature oxidation, duplex oxides containing Co and Cr were formed. It was thermodynamically elucidated that when the growing scale was thick enough, the partial pressure of O<inf>2</inf> in the scale dropped. Then, the reduction of CoO occurred for promoting O<inf>2</inf> which was responsible for Cr<inf>2</inf>O<inf>3</inf> production. This work experimentally proved this point by in situ char-acterising Co-27Cr-6Mo at high temperatures in air by X-ray diffractometer in a grazing incident mode and metallic Co was confirmed to be formed by the reduction of CoO consistent with the image taken and analysed by field emission scanning electron microscope, energy-dispersive X-ray, and electron backscatter diffraction. Furthermore, the change in lattice parameter and the phase transition were observed when the temperature was altered.
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A study of atrazine adsorption by using the rice straw synthesized adsorbent
(2018-08-14)
Samanmulya, Thachanan
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Deetae, Pawinee
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Wongpromrat, Patthranit
This study focused on adsorption of atrazine in adsorbent synthesized from Rice Straw. Rice Straw biochar were used in the study as they exhibited significantly high adsorption capacity for pesticide. Briefly, rice straw was pyrolysis at 600°C under nitrogen then biochar was modified using H<inf>3</inf>PO<inf>4</inf>. Biochar were characterized for their physico-chemical characteristics. The elemental analysis of biochar was performed using CHNS Analysis. The surface area and pore volume of adsorbents were estimated using the Brunauer, Emmett, and Teller (BET Analysis). In parts of Batch adsorption experiments was performed in range of room temperature and were divided to 2 parts. Part 1: Study of the kinetics adsorption was investigated using two models, namely, the pseudo-first-order and the pseudo-second-order models. Part 2: study of Adsorption isotherms. The results of CHNS analysis shows the elemental analysis that 51.795% of C, 0.763% of H, 1.634% of N and 0.654 % of S and the result of BET Analysis shows the surface area is 372.4 m2/g and pore volume of adsorbents is 0.315 cm3. From plotting between qt(mg/g) and time (t) shows the dynamics of the adsorption of atrazine onto the biochar at 15 ppm of initial atrazine concentrations. In general, atrazine was adsorbed quickly around 1-30 min. This could be due to fast mass transfer of solute from the solution to surface of adsorbent s as a result of concentration gradient of the solute. The study of the kinetics adsorption showed that the pseudo-second-order model best described the adsorption which agrees with chemisorption as the rate controlling mechanism.
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Mathematical optimization of the anti-corrosive rice husk ash enhanced concrete under marine environment
(2018-01-01)
Wongpromrat, Patthranit
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Anantpinijwatna, Amata
Chloride induced steel corrosion causes safety and stability problems to the reinforced concrete structure located closed to or under marine environment. The corrosive steel rust could potentially lead to surface swelling altering the external appearance, generating the concrete cracking, lowering the elasticity, reducing tensile strength, and thus leading to the deterioration of the concrete structure. Recent studies present an innovative method for inhibiting chloride corrosion by the addition of fibres into concrete to improve its toughness and tensile properties. By the addition of high fineness rice husk ash (RHA), the RHA would function as chloride adsorbent, preventing the chloride penetration through the concrete into the steel foundation. However, the addition of the RHA also affects the compressive strength, the workability, the consistency, and the slump of the concrete structure, limiting the mixed amount of the RHA that could be added in the concrete. A linear optimization model of the anti-corrosive RHA enhanced concrete has been formulated with the objective to minimize the effect of the chloride corrosion of the steel; whereas, the amount of the mixed RHA is limited by the critical concrete strength in term of modulus elasticity. In this study, the mass transfer coefficient, adsorption coefficient, and the Langmuir equilibrium isotherm are taken from the literatures. The chloride concentration is assumed to be 3.5 % w/v of the total chloride ion in salt water. The model has been validated with the measured data collected from open literatures. The optimum ratio between the RHA and cement mixture is discovered to be based on the void fraction of the concrete mixture. The optimum ratio is found to be around 10 % at the void fraction 0.8 and increasing to 25 % at the void fraction 1.2.
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Evidence for chromium, cobalt and molybdenum volatilisations during high temperature oxidation of Co-27Cr-6Mo Alloy
(2022-07-01)
Wongpromrat, Patthranit
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Galerie, Alain
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Thublaor, Thammaporn
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Chandra-ambhorn, Walairat
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Ponpo, Phisan
A Co-27Cr-6Mo alloy was oxidised in pure O<inf>2</inf> between 800 and 1000 °C for durations up to 96 h. The flow rate was varied between 2 and 5 cm.s–1. In these conditions, volatilisations of chromium, cobalt and molybdenum were observed. The chromium volatilisation values were in good agreement with calculations assuming (CrO<inf>3</inf>)g volatilisation limited by diffusion in the gas boundary layer. On the contrary, the measured flux of evaporated Co was higher than the calculated Co volatilisation flux from the metallic Co. The theoretical relation between the solid Co particle size and its vapour pressure was suggested to help explaining such difference.
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Xps analysis of oxide formed on the surface of co-28cr-6mo-1si alloy oxidized at 550 ºc
(2020-01-01)
Tunthawiroon, Phacharaphon
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Kitiwan, Mettaya
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Wongpromrat, Patthranit
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Chiba, Akihiko
This work investigated the influence of oxidation durations on the formation of oxide on the surface of wrought Co-28Cr-6Mo-1Si alloy. The iso-thermal oxidation was individually performed in air at 550ºC for 4, 12 and 24 h. For comparison, the surface of the non-oxidized Co-28Cr-6Mo-1Si alloy was concurrently examined. The chemical compositions of the non-oxidized and oxidized alloys were principally analyzed via X-ray photoelectron spectroscopy (XPS). The XPS results revealed that the surface of the non-oxidized alloy enriched in Cr-oxide. After oxidation treatment, the Co-oxide, existing as Co2+ state was observed coexisting with two Cr-oxide states, Cr3+ and Cr4+. The low concentrations of Mo6+ were also observed on the oxidized alloy surface. With the increase in oxidation durations, the Co-oxide was suppressed by Cr-oxide. The XPS depth profile analysis indicated that the thickness of the oxide film increased with increasing the oxidation duration.
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Characterisation of thermal oxide scales on stainless steels
(2020-01-01)
Srisrual, Anusara
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Thublaor, Thammaporn
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Wongpromrat, Patthranit
This chapter aims at reviewing the characterisation techniques that are commonly used for high temperature oxidation study, especially on stainless steels. In addition, the experimental studies about the high temperature oxidation i.e. thermogravimetric method and chromium volatilisation measurement are explained. The various kinds of characterisation techniques for physico-chemical and electronic properties of thermal oxide scales are reviewed, starting from optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), focused ion beam coupled with scanning electron microscope (FIB/SEM), X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy (RS), and photoelectrochemical characterisation (PEC). The review focuses on the basic concepts and shows how the characterising tools can be applied to thermal oxide characterisation.
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Corrosion Resistance Enhancement of Reinforced Concrete in Marine Environment by Partial Replacement of Black Rice Husk Ash
(2023-01-01)
Chandra-Ambhorn, Walairat
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Bumrungthaichaichan, Eakarach
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Rotchan, Chayanit
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Haema, Narunat
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Wongpromrat, Patthranit
In this work, the black rice husk ash (BRHA), a pozzolanic material, was used as a partial replacement in concrete with the weight percentages of 0%, 10%, 20%, 30%, 40% and 50% for enhancing the corrosion resistivity in the marine environment. The compressive strength, corrosion by accelerated corrosion test by impressed voltage (ACTIV), and chloride (Cl− ) penetration of concrete specimens were investigated after 28 days of curing. For corrosion and chloride penetration analyses, the 20% of BRHA replacement specimen was the most effective concrete specimen because the deformation was not observed within 19 days of the test. The cement specimens with lower BRHA percentages were cracked due to the development of stress by the rust formation. For higher BRHA percentages, the protective Fe2O3 was dissolved due to the acidic environment caused by higher chloride accumulation in the cement specimens. The steel rebar was then aggressively attacked by the chloride and it was finally broken. Therefore, the optimization of the BRHA percentage is needed to minimize corrosion. However, the longer curing time of 20% BRHA replacement specimen is required for increasing the compressive strength because its compressive strength is slightly lower than the standard.

Wongpromrat, Patthranit

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