Papers by Keyword: Hydrolysis

Abstract: Procion M dyes are widely used reactive dyes for cellulose-based textiles due to their bright colors, fastness properties, and covalent bonding capabilities. This study examines the chemical structure of Procion M dyes, highlighting key components: the chromophore, reactive group, solubilizing group, and linking group. The hydrolysis and alcoholysis of these dyes were investigated using Procion Red M-X5B and Procion Blue M-XG under various temperatures (25°C, 35°C, 45°C). Experimental setups included UV-Vis and IR spectroscopy to monitor dye concentration and functional group changes, respectively. Data revealed temperature-dependent reaction rates, with higher temperatures accelerating both hydrolysis and alcoholysis. Thermodynamic analysis showed that both processes are exothermic and spontaneous, with enthalpy changes of -20 kJ/mol (hydrolysis) and -25 kJ/mol (alcoholysis), and Gibbs free energy changes confirming spontaneity. FTIR and HPLC analyses provided insights into molecular structural changes and product formation. These results underscore the efficiency and temperature sensitivity of Procion M dye reactions, offering valuable information for optimizing textile dyeing processes.

Abstract: It is important for consumers to be aware of the source of gelatin due to religious restrictions, as pork is forbidden for consumption by Muslims and Jews, and cows are forbidden for consumption by Hindus. Fishery waste, such as fish bones and scales, can be a promising alternative raw material for gelatin production, as they are halal for consumption. The process of gelatin preparation involves several stages, including pretreatment, degreasing, demineralization, and hydrolysis using bromelain enzyme. hydrolysis process using bromelain enzyme ranging from 1, 2, 3, 4, 5, 6 and 7% at 300 rpm and temperature 55 °C. Hydrolysis was carried out for 6 hours and 9 hours for each concentration. Characterizations of gelatin was conducted for pH, water content, ash content, Fourier Transform-Infrared Analyzer (FTIR), X-ray Fluorescence (XRF) Spectrometry and Gas chromatography (GC). Based on the research, the optimum conditions for produce halal gelatin from red snapper scales was obtained at 5% bromelain enzyme for 9 hours for hydrolized collagen to gelatin with a yield of 11.414%, pH of 5.3, water content of 7%, ash content of 2.1%, and free from alcohol and heavy metals. The FTIR spectra show that the absorption at wavenumber 2944.5, 1628.74, 1524.55, and 1332.14 cm^-1 respectively, indicating the presence of C–H, C=O, C=C and C–N stretching. The presence of absorption peaks of that functional groups show gelatin has been formed. XRF analysis show the absence of heavy metals as Hg, Pb, Cd, and Zn. Fish-based gelatin in this study is produced through a halal process, using halal ingredients, and its product does not contain alcohol, thus the gelatin produced in this study is a halal product.

Abstract: Silica based catalyst was prepared from geothermal sludge – solid waste from geothermal exploration - of Dieng Power Station, Central Java, Indonesia. The catalyst was prepared by extracting silica compound from the sludge matrix, followed by sulfonation to obtain sulfonated – solid catalyst. Catalyst sample analysis informed the catalyst was generally amorphous in structures, possessed surface area between 76 – 81 m²/g, with acidity approximately 5-6 mmol/g. Evaluation on catalyst activity was performed by applying it on sago starch hydrolysis - atmospheric pressure and 100 – 150°C (373 – 423 K) - in which more than 90 % conversion could be achieved.

Abstract: Catalyst is a substance that is widely used in chemical reactions to obtain certain products. This study has been focusing on preparing and employing solid catalyst derived from geothermal sludge (GS) as waste material from Dieng Geothermal Power Plant (PLTPB) activity. The methodology of catalyst preparation was extraction of silica from the sludge by alkali solution, followed by gelling formation and acidification with sulfuric acid solution. The prepared catalyst was then applied in hydrolysis reaction to convert sago flour into glucose.Catalyst properties were assessed in term of morphology, crystallinity, surface area, and activity (hydrolysis reaction). Sample analysis confirmed the produced catalyst was amorphous in general, having 127 m²/g of surface area. In addition, the prepared catalyst contained 78 - 79 % of silica, a significant increase - as a result of preparation - from that of raw material sludge which had 33 - 43 % silica. From the catalyst activity test conducted at 120 - 185°C hydrolysis reaction, as much as 50 % of glucose yield could be obtained from sago starch conversion, indicating prospective catalyst performance.Keyword: Sulfonated SiO₂, Catalyst, Geothermal Sludge Waste, Sago, Hydrolysis

Abstract: This study develops an absorber containing abaca fiber (Musa Textiles) and epoxy resin as a binder. The ability to absorb sound energy is related to the pore’s size present in the absorber. One of the methods to create porosity is to vary the length of fiber, which is 1, 10 mm, 15 mm and 20 mm. Before the fiber is cut to be certain length, it is treated employing NaOH alkalization and acetic acid hydrolysis. The characterization carried out includes density, morphology and absorption coefficient measurement using impedance tubes. Moreover, the fibers are measured for the density, then continued to determine the porosity and air flow resistivity using the Konzeny-Carman equation. The air flow resistivity parameter is utilized to determine the absorption coefficient using Delany-Bazley model. The value of the absorption coefficient from experiments using impedance tubes and based on theoretical analysis shows a similar trend curve. The results show that the fiber with the length of 20 mm exhibits the highest sound absorption coefficient.

Abstract: The development of the palm oil industry is followed by the increased amount of lignocellulosic biomass waste. Lignocellulosic biomass waste contains cellulose and hemicellulose which are potential sources of C6 and C5 sugars. C5 or pentose can be hydrolyzed into furfural through the hydrolysis process and then dehydration reaction using the acid catalyst in various kinds of solvent. At this moment, the highest yield of furfural in the acid-catalyzed hydrolysis of xylose in water resulted in only about 50.0w-%. Other methods such as salt addition or the use of various organic solvents lead to new challenges both in purification and environmental issues. Therefore in this study, 70.0w-% ethanol in water was utilized as the solvent in a range of temperatures (140-170°C) and concentration of sulfuric acid (0.1-0.5M) up to 120 minutes reaction time. As the outcomes, the shorter time was needed to achieve maximum furfural yield with the increase of temperature and acid concentration with the water and the ethanol as the solvent. Improvement was shown in the highest furfural yield achieved up to 70.0-72.0mol-% (after 15 min at 170°C, 0.2-0.5 M concentration of H₂SO₄). The results showed the potential use of ethanol as a green solvent to produce furfural from xylose.

Abstract: Platinum (Pt), a noble metal, is known for its ability to regenerate and be recycled even without any reactivation procedure, and still demonstrated good stability. The cost of the noble metal can be reduced by incorporating the metal into the pores of catalyst support rather than using it individually. Hence, in this research study, 4 wt.% Pt supported on silica-alumina (SiO₂-Al₂O₃) and gamma-alumina (γ-Al₂O₃) was synthesized using wet impregnation method, then followed by catalyst calcination at 500 °C. The catalyst was then characterized using Thermogravimetric Analysis (TGA), Fourier-Transform Infrared Spectroscopy (FTIR), Brunauer–Emmett–Teller (BET), and particle size analyzer where catalyst with high surface area and pore volume demonstrated an excellent performance for the catalytic reaction of cellulose. Experimental results showed that catalyst Pt/SiO₂-Al₂O₃ with the highest surface area and pore volume (466.4 m²/g and 0.1157 cm³/g, respectively) exhibited the highest catalytic performance with the conversion of cellulose up to 65.8% and 30.9% levulinic acid (LA) yield produced at the reaction temperature of 200 °C in a semi-batch reactor for 8 hrs.

Abstract: Bamboo saw dust (BSD) as reducing agent in low-grade manganese ore leaching is used, and therefore the performance of cellulose hydrolysis will affect the percent recovery of Mn ore. This work is studies the effect of sulphuric acid and speed rotation on hydrolysis of BSD. The crytallinity of BSD were investigated. The parameters considered in this work are sulphuric acid concentration and the speed rotation by using 2³ +3 factorial design. The significant factor, main and interaction effect were investigated based on Analysis of Variance obtained from statistical software. It shows that the sulphuric acid concentration is the main factors that affects the percentercent crystallinity compared to rotation speed. It is proved by the DOE analysis and supported by the crystallinity analysis of BSD before and after hydrolysis process. The optimum condition that can be suggested to obtain low percent crystallinity are when the sulphuric acid concentration and speed rotation at 4M and 400 rpm respectively. This indicates that reducing agent can be obtained from BSD in mild condition of hydrolysis due to decrement of cellulose crystallinity

Abstract: The purpose of this study is to present a suitable production process of a carbonated drink from ingredients originated from red flesh dragon fruits. Additionally, optimal parameters in the hydrolysis and pasteurization stages of the juice were determined so that the product could retain the highest bioactive ingredients while still maintaining favorable color. The investigated parameters of pectinase hydrolysis process included hydrolysis temperature (35, 40, 45 and 50oC), hydrolysis time (1 hour, 2 hours, 3 hours and 4 hours), concentration pectinase enzyme level (0.4; 0.6, 0.8 and 1%) and enzyme pectinase content (0.2, 0.4, 0.6 and 0.8%). Outcomes which were considered in optimization processes included polyphenol content, vitamin C content and DPPH scavenging activity. The results are expected to aid in diversification of products from dragon fruit raw materials to meet the increasing demand of consumers.

Abstract: S. platensis is a microalga that contains carbohydrate composition of 30.21% which makes it potential to be used as raw material for ethanol production. Hydrolysis of S. platensis is the first step for converting its carbohydrates into monosaccharides. The second step is fermentation of monosaccharides into ethanol. This research aims to study the effect of temperature and microalgae concentration on the hydrolysis of S. platensis using sulfuric acid as catalyst. This research was conducted using 300 mL sulfuric acid of 2 mol/L, hydrolysis temperatures of 70, 80 and 90 °C, and microalgae concentrations of 20, 26.7, and 33.3 g/L. The effect of temperature is significant in the hydrolysis of S. platensis using sulfuric acid. At microalgae concentration of 20 g/L and hydrolysis time of 35 minutes, the higher the temperatures (70, 80, and 90 °C), the more the glucose yields would be (8.9, 13.5, and 22.9%). This temperature effect got stronger when the hydrolysis was running for 15 minutes. Every time the hydrolysis temperature increased by 10 °C, the glucose yield increased by 13.0% at microalgae concentration of 33.3 g/L. At temperature of 90 °C and time of 35 minutes, the higher the microalgae concentrations (20, 26.7, and 33.3 g/L), the higher the glucose yields would be (25.5, 27.7, and 28.2%). The highest glucose concentration obtained was 2.82 g/L at microalgae concentration of 33.3 g/L, temperature of 90 °C, and time of 35 minutes.