Search results for: NaOH pretreatment
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 435

Search results for: NaOH pretreatment

435 Effects of Alkaline Pretreatment Parameters on the Corrosion Resistance and ‎Wettability of Magnesium Implant

Authors: Mahtab Assadian, Mohd Hasbullah Idris, Mostafa Rezazadeh Shirdar, Mohammad Mahdi Taheri, ‎S. Izman

Abstract:

Corrosion behaviour and surface roughness of magnesium substrate were investigated after NaOH pretreatment in different concentrations (1, 5, and 10 molar) and duration of (10 min, 30 min, 1 h, 3 h, 6 h and 24 h). Creation of Mg(OH)2 barrier layer after pretreatment enhanced corrostion resistance as well as wettability of substrate surface. Characterization including Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) was conducted to detect the existence of this barrier layer. Surface roughness and wettability of substrate was evaluated using atomic force microscopy (AFM) and contact angle measurement respectively. It is found that magnesium treated by 1M NaOH for 30 min reveals higher corrosion resistance and lower water contact angle of substrate surface. In addition, this investigation indicates that pH value of SBF solution is strongly influenced by different time and concentration of alkaline pretreatment.

Keywords: magnesium, NaOH pretreatment, corrosion resistance, wettability

Procedia PDF Downloads 961
434 Development of a Steam or Microwave-Assisted Sequential Salt-Alkali Pretreatment for Sugarcane Leaf Waste

Authors: Preshanthan Moodley

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This study compares two different pretreatments for sugarcane leaf waste (SLW): steam salt-alkali (SSA) and microwave salt-alkali (MSA). The two pretreatment types were modelled, optimized, and validated with R² > 0.97. Reducing sugar yields of 1.21g/g were obtained with optimized SSA pretreatment using 1.73M ZnCl₂, 1.36M NaOH and 9.69% solid loading, and 1.17g/g with optimized MSA pretreatment using 1.67M ZnCl₂, 1.52M NaOH at 400W for 10min. A lower pretreatment time (10min) was required for the MSA model (83% lower). The structure of pretreated SLW was assessed using scanning electron microscopy (SEM) and Fourier Transform Infrared analysis (FTIR). The optimized SSA and MSA models showed lignin removal of 80.5 and 73% respectively. The MSA pretreatment was further examined on sorghum leaves and Napier grass and showed yield improvements of 1.9- and 2.8-fold compared to recent reports. The developed pretreatment methods demonstrated high efficiency at enhancing enzymatic hydrolysis on various lignocellulosic substrates.

Keywords: lignocellulosic biomass, pretreatment, salt, sugarcane leaves

Procedia PDF Downloads 264
433 Optimization of NaOH Thermo-Chemical Pretreatment to Enhance Solubilisation of Organic Food Waste by Response Surface Methodology

Authors: Hafizan Junoh, Kumaran Palanisamy, Yip Chan Heng, Pua Fei Ling

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This study investigates the influence of low temperature thermo-chemical pretreatment of organic food waste on the performance of COD solubilisation. Both temperature and alkaline agent were reported to have an effect on solubilizing any possible biomass including organic food waste. The three independent variables considered in this pretreatment were temperature (50-90oC), pretreatment time (30-120 minutes) and alkaline concentration, sodium hydroxide, NaOH (0.7-15 g/L). The optimal condition obtained were 90oC, 15 g/L NaOH for 2 hours. Solubilisation has potential in enhancing methane production by providing a high amount of soluble components at an early stage during anaerobic digestion.

Keywords: food waste, pretreatments, respond surface methodology, ANOVA, anaerobic digestion

Procedia PDF Downloads 554
432 Thermochemical and Biological Pretreatment Study for Efficient Sugar Release from Lignocellulosic Biomass (Deodar and Sal Wood Residues)

Authors: Neelu Raina, Parvez Singh Slathia, Deepali Bhagat, Preeti Sharma

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Pretreatment of lignocellulosic biomass for generating suitable substrates (starch/ sugars) for conversion to bioethanol is the most crucial step. In present study waste from furniture industry i.e sawdust from softwood Cedrus deodara (deodar) and hardwood Shorea robusta (sal) was used as lignocellulosic biomass. Thermochemical pretreatment was given by autoclaving at 121°C temperature and 15 psi pressure. Acids (H2SO4,HCl,HNO3,H3PO4), alkali (NaOH,NH4OH,KOH,Ca(OH)2) and organic acids (C6H8O7,C2H2O4,C4H4O4) were used at 0.1%, 0.5% and 1% concentration without giving any residence time. 1% HCl gave maximum sugar yield of 3.6587g/L in deodar and 6.1539 g/L in sal. For biological pretreatment a fungi isolated from decaying wood was used , sawdust from deodar tree species was used as a lignocellulosic substrate and before thermochemical pretreatment sawdust was treated with fungal culture at 37°C under submerged conditions with a residence time of one week followed by a thermochemical pretreatment methodology. Higher sugar yields were obtained with sal tree species followed by deodar tree species, i.e., 6.0334g/L in deodar and 8.3605g/L in sal was obtained by a combined biological and thermochemical pretreatment. Use of acids along with biological pretreatment is a favourable factor for breaking the lignin seal and thus increasing the sugar yield. Sugar estimation was done using Dinitrosalicyclic assay method. Result validation is being done by statistical analysis.

Keywords: lignocellulosic biomass, bioethanol, pretreatment, sawdust

Procedia PDF Downloads 413
431 Pretreatment of Cattail (Typha domingensis) Fibers to Obtain Cellulose Nanocrystals

Authors: Marivane Turim Koschevic, Maycon dos Santos, Marcello Lima Bertuci, Farayde Matta Fakhouri, Silvia Maria Martelli

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Natural fibers are rich raw materials in cellulose and abundant in the world, its use for the cellulose nanocrystals extraction is promising as an example cited is the cattail, macrophyte native weed in South America. This study deals with the pre-treatment cattail of crushed fibers, at six different methods of mercerization, followed by the use of bleaching. As a result, have found The positive effects of treating fibers by means of optical microscopy and spectroscopy, Fourier transform (FTIR). The sample selected for future testing of cellulose nanocrystals extraction was treated in 2.5% NaOH for 2 h, 60 °C in the first stage and 30vol H2O2, NaOH 5% in the proportion 30/70% (v/v) for 1 hour 60 °C, followed by treatment at 50/50% (v/v) 15 minutes, 50°C, with the same constituents of the solution.

Keywords: cellulose nanocrystal, chemical treatment, mercerization, natural fibers

Procedia PDF Downloads 293
430 Analysis Influence Variation Frequency on Characterization of Nano-Particles in Preteatment Bioetanol Oil Palm Stem (Elaeis guineensis JACQ) Use Sonication Method with Alkaline Peroxide Activators on Improvement of Celullose

Authors: Luristya Nur Mahfut, Nada Mawarda Rilek, Ameiga Cautsarina Putri, Mujaroh Khotimah

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The use of bioetanol from lignocellulosic material has begone to be developed. In Indonesia the most abundant lignocellulosic material is stem of palm which contain 32.22% of cellulose. Indonesia produces approximatelly 300.375.000 tons of stem of palm each year. To produce bioetanol from lignocellulosic material, the first process is pretreatment. But, until now the method of lignocellulosic pretretament is uneffective. This is related to the particle size and the method of pretreatment of less than optimal so that led to an overhaul of the lignin insufficient, consequently increased levels of cellulose was not significant resulting in low yield of bioetanol. To solve the problem, this research was implemented by using the process of pretreatment method ultasonifikasi in order to produce higher pulp with nano-sized particles that will obtain higher of yield ethanol from stem of palm. Research methods used in this research is the RAK that is composed of one factor which is the frequency ultrasonic waves with three varians, they are 30 kHz, 40 kHz, 50 kHz, and use constant variable is concentration of NaOH. The analysis conducted in this research is the influence of the frequency of the wave to increase levels of cellulose and change size on the scale of nanometers on pretreatment process by using the PSA methods (Particle Size Analyzer), and a Cheason. For the analysis of the results, data, and best treatment using ANOVA and test BNT with confidence interval 5%. The best treatment was obtained by combination X3 (frequency of sonication 50 kHz) and lignin (19,6%) cellulose (59,49%) and hemicellulose (11,8%) with particle size 385,2nm (18,8%).

Keywords: bioethanol, pretreatment, stem of palm, cellulosa

Procedia PDF Downloads 327
429 Microwave-Assisted Inorganic Salt Pretreatment of Sugarcane Leaf Waste

Authors: Preshanthan Moodley, E. B. Gueguim-Kana

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The objective of this study was to develop a method to pretreat sugarcane leaf waste using microwave-assisted (MA) inorganic salt. The effects of process parameters of salt concentration, microwave power intensity and pretreatment time on reducing sugar yield from enzymatically hydrolysed sugarcane leaf waste were investigated. Pretreatment models based on MA-NaCl, MA-ZnCl2 and MA-FeCl3 were developed. Maximum reducing sugar yield of 0.406 g/g was obtained with 2 M FeCl3 at 700W for 3.5 min. Scanning electron microscopy (SEM) and Fourier Transform Infrared analysis (FTIR) showed major changes in lignocellulosic structure after MA-FeCl3 pretreatment with 71.5 % hemicellulose solubilization. This pretreatment was further assessed on sorghum leaves and Napier grass under optimal MA-FeCl3 conditions. A 2 fold and 3.1-fold increase in sugar yield respectively were observed compared to previous reports. This pretreatment was highly effective for enhancing enzymatic saccharification of lignocellulosic biomass.

Keywords: acid, pretreatment, salt, sugarcane leaves

Procedia PDF Downloads 452
428 Optimization of Diluted Organic Acid Pretreatment on Rice Straw Using Response Surface Methodology

Authors: Rotchanaphan Hengaroonprasan, Malinee Sriariyanun, Prapakorn Tantayotai, Supacharee Roddecha, Kraipat Cheenkachorn

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Lignocellolusic material is a substance that is resistant to be degraded by microorganisms or hydrolysis enzymes. To be used as materials for biofuel production, it needs pretreatment process to improve efficiency of hydrolysis. In this work, chemical pretreatments on rice straw using three diluted organic acids, including acetic acid, citric acid, oxalic acid, were optimized. Using Response Surface Methodology (RSM), the effect of three pretreatment parameters, acid concentration, treatment time, and reaction temperature, on pretreatment efficiency were statistically evaluated. The results indicated that dilute oxalic acid pretreatment led to the highest enhancement of enzymatic saccharification by commercial cellulase and yielded sugar up to 10.67 mg/ml when using 5.04% oxalic acid at 137.11 oC for 30.01 min. Compared to other acid pretreatment by acetic acid, citric acid, and hydrochloric acid, the maximum sugar yields are 7.07, 6.30, and 8.53 mg/ml, respectively. Here, it was demonstrated that organic acids can be used for pretreatment of lignocellulosic materials to enhance of hydrolysis process, which could be integrated to other applications for various biorefinery processes.

Keywords: lignocellolusic biomass, pretreatment, organic acid response surface methodology, biorefinery

Procedia PDF Downloads 654
427 Development of Microwave-Assisted Alkalic Salt Pretreatment Regimes for Enhanced Sugar Recovery from Corn Cobs

Authors: Yeshona Sewsynker

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This study presents three microwave-assisted alkalic salt pretreatments to enhance delignification and enzymatic saccharification of corn cobs. The effects of process parameters of salt concentration (0-15%), microwave power intensity (0-800 W) and pretreatment time (2-8 min) on reducing sugar yield from corn cobs were investigated. Pretreatment models were developed with the high coefficient of determination values (R2>0.85). Optimization gave a maximum reducing sugar yield of 0.76 g/g. Scanning electron microscopy (SEM) and Fourier Transform Infrared analysis (FTIR) showed major changes in the lignocellulosic structure after pretreatment. A 7-fold increase in the sugar yield was observed compared to previous reports on the same substrate. The developed pretreatment strategy was effective for enhancing enzymatic saccharification from lignocellulosic wastes for microbial biofuel production processes and value-added products.

Keywords: pretreatment, lignocellulosic biomass, enzymatic hydrolysis, delignification

Procedia PDF Downloads 499
426 Effect of Ultrasound-Assisted Pretreatment on Saccharification of Spent Coffee Grounds

Authors: Shady S. Hassan, Brijesh K. Tiwari, Gwilym A. Williams, Amit K. Jaiswal

Abstract:

EU is known as the destination with the highest rate of the coffee consumption per capita in the world. Spent coffee grounds (SCG) are the main by-product of coffee brewing. SCG is either disposed as a solid waste or employed as compost, although the polysaccharides from such lignocellulosic biomass might be used as feedstock for fermentation processes. However, SCG as a lignocellulose have a complex structure and pretreatment process is required to facilitate an efficient enzymatic hydrolysis of carbohydrates. However, commonly used pretreatment methods, such as chemical, physico-chemical and biological techniques are still insufficient to meet optimal industrial production requirements in a sustainable way. Ultrasound is a promising candidate as a sustainable green pretreatment solution for lignocellulosic biomass utilization in a large scale biorefinery. Thus, ultrasound pretreatment of SCG without adding harsh chemicals investigated as a green technology to enhance enzyme hydrolysis. In the present work, ultrasound pretreatment experiments were conducted on SCG using different ultrasound frequencies (25, 35, 45, 130, and 950 kHz) for 60 min. Regardless of ultrasound power, low ultrasound frequency is more effective than high ultrasound frequency in pretreatment of biomass. Ultrasound pretreatment of SCG (at ultrasound frequency of 25 kHz for 60 min) followed by enzymatic hydrolysis resulted in total reducing sugars of 56.1 ± 2.8 mg/g of biomass. Fourier transform Infrared Spectroscopy (FTIR) was employed to investigate changes in functional groups of biomass after pretreatment, while high-performance liquid chromatography (HPLC) was employed for determination of glucose. Pretreatment of lignocellulose by low frequency ultrasound in water only was found to be an effective green approach for SCG to improve saccharification and glucose yield compared to native biomass. Pretreatment conditions will be optimized, and the enzyme hydrolysate will be used as media component substitute for the production of ethanol.

Keywords: lignocellulose, ultrasound, pretreatment, spent coffee grounds

Procedia PDF Downloads 323
425 Fermentable Sugars from Palm Empty Fruit Bunch Biomass for Bioethanol Production

Authors: U. A. Asli, H. Hamid, Z. A. Zakaria, A. N. Sadikin, R. Rasit

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This study investigated the effect of a dilute acid, lime and ammonia aqueous pretreatment on the fermentable sugars conversion from empty fruit bunch (EFB) biomass. The dilute acid treatment was carried out in an autoclave, at 121ºC with 4 % of sulphuric acid. In the lime pretreatment, 3 wt % of calcium hydroxide was used, whereas the third method was done by soaking EFB with 28 % ammonia solution. Then the EFB biomass was subjected to a two-stage-acid hydrolysis process. Subsequently, the hydrolysate was fermented by using instant baker’s yeast to produce bioethanol. The highest glucose yield was 890 mg/g of biomass, obtained from the sample which underwent lime pretreatment. The highest bioethanol yield of 6.1mg/g of glucose was achieved from acid pretreatment. This showed that the acid pretreatment gave the most fermentable sugars compared to the other two pretreatments.

Keywords: bioethanol, biomass, empty fruit bunch (EFB), fermentable sugars

Procedia PDF Downloads 616
424 Studies of Carbohydrate, Antioxidant, Nutrient and Genomic DNA Characterization of Fresh Olive Treated with Alkaline and Acidic Solvent: An Innovation

Authors: A. B. M. S. Hossain, A. Abdelgadir, N. A. Ibrahim

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Fresh ripen olive cannot be consumed immediately after harvest due to the excessive bitterness having polyphenol as antioxidant. Industrial processing needs to be edible the fruit. The laboratory processing technique has been used to make it edible by using acid (vinegar, 5% acetic acid) and alkaline solvent (NaOH). Based on the treatment and consequence, innovative data have been found in this regard. The experiment was conducted to investigate biochemical content, nutritional and DNA characterization of olive fruit treated with alkaline (Sodium chloride anhydrous) and acidic solvent (5% acetic acid, vinegar). The treatments were used as control (no water), water control, 10% sodium chloride anhydrous (NaOH), vinegar (5% acetic acid), vinegar + NaOH and vinegar + NaOH + hot water treatment. Our results showed that inverted sugar and glucose content were higher in the vinegar and NaOH treated olive than in other treatments. Fructose content was the highest in vinegar + NaOH treated fruit. Nutrient contents NO3 K, Ca and Na were found higher in the treated fruit than the control fruit. Moreover, maximum K content was observed in the case of all treatments compared to the other nutrient content. The highest acidic (lower pH) condition (sour) was found in treated fruit. DNA yield was found higher in water control than acid and alkaline treated olives. DNA band was wider in the olive treated water control compared to the NaOH, vinegar, vinegar + NaOH and vinegar + NaOH + Hot water treatment. Finally, results suggest that vinegar + NaOH treated olive fruit was the best for fresh olive homemade processing after harvesting for edible purpose.

Keywords: olive, vinegar, sugars, DNA band, bioprocess biotechnology

Procedia PDF Downloads 185
423 Comparison of Acid and Base Pretreatment of Switchgrass (Panicum virgatum L.) for Bioethanol Production

Authors: Mustafa Ümi̇t Ünal, Nafi̇z Çeli̇ktaş, Aysun Şener, Sara Betül Dolgun, Duygu Keser

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The aim of this study was to compare acid and base pretreatment of switchgrass for bioethanol production. Switchgrass was pretreated with sulfuric acid and sodium hydroxide at 0.5, 1.0 and 1.5% (v/v) at 120, 140, 180 °C for 10, 60 and 90. Optimization of enzymatic hydrolysis of the pretreated switchgrass samples were carried out using three different enzyme mixtures (22.5 mg cellulase and 75 mg cellobiase /g biomass; 45 mg cellulase and 150 mg cellobiase /g biomass; 90 mg cellulase and 300 mg cellobiase /g biomass). Samples were removed at 24-h interval for fermentable sugar analyses with HPLC. The results showed that use of 90 mg cellulase and 300 mg cellobiase/g biomass resulted in the highest fermentable sugar formation. Furthermore, the highest fermentable sugar yield was obtained by pretreatment at 120 °C for 10 min using 1.0 % sodium hydroxide.

Keywords: switchgrass, acid pretreatment, enzymatic hydrolysis, base pretreatment, ethanol production

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422 Regenerated Cellulose Prepared by Using NaOH/Urea

Authors: Lee Chiau Yeng, Norhayani Othman

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Regenerated cellulose fiber is fabricated in the NaOH/urea aqueous solution. In this work, cellulose is dissolved in 7 .wt% NaOH/12 .wt% urea in the temperature of -12 °C to prepare regenerated cellulose. Thermal and structure properties of cellulose and regenerated cellulose was compared and investigated by Field Emission Scanning Electron Microscopy (FeSEM), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Thermogravimetric analysis (TGA), and Differential Scanning Calorimetry. Results of FeSEM revealed that the regenerated cellulose fibers showed a more circular shape with irregular size due to fiber agglomeration. FTIR showed the difference in between the structure of cellulose and the regenerated cellulose fibers. In this case, regenerated cellulose fibers have a cellulose II crystalline structure with lower degree of crystallinity. Regenerated cellulose exhibited better thermal stability than the cellulose.

Keywords: regenerated cellulose, cellulose, NaOH, urea

Procedia PDF Downloads 431
421 Cellulose Extraction from Pomelo Peel: Synthesis of Carboxymethyl Cellulose

Authors: Jitlada Chumee, Drenpen Seeburin

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The cellulose was extracted from pomelo peel and an etherification reaction used for converting cellulose to carboxymethyl cellulose (CMC). The pomelo peel was refluxed with 0.5 M HCl and 1 M NaOH solution at 90°C for 1 h and 2 h, respectively. The cellulose was bleached with calcium hypochlorite and used as precursor. The precursor was soaked in mixed solution between isopropyl alcohol and 40%w/v NaOH for 12 h. After that, chloroacetic acid was added and reacted at 55°C for 6 h. The optimum condition was 5 g of cellulose: 0.25 mole of NaOH : 0.07 mole of ClCH2COOH with 78.00% of yield. Moreover, the product had 0.54 of degree of substitution (DS).

Keywords: pomelo peel, carboxymethyl cellulose, bioplastic, extraction

Procedia PDF Downloads 314
420 Optimal Consume of NaOH in Starches Gelatinization for Froth Flotation

Authors: André C. Silva, Débora N. Sousa, Elenice M. S. Silva, Thales P. Fontes, Raphael S. Tomaz

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Starches are widely used as depressant in froth flotation operations in Brazil due to their efficiency, increasing the selectivity in the inverse flotation of quartz depressing iron ore. Starches market have been growing and improving in recent years, leading to better products attending the requirements of the mineral industry. The major source of starch used for iron ore is corn starch, which needs to be gelatinized with sodium hydroxide (NaOH) prior to use. This stage has a direct impact on industrials costs, once the lowest consumption of NaOH in gelatinization provides better control of the pH in the froth flotation and reduces the amount of electrolytes present in the pulp. In order to evaluate the gelatinization degree of different starches and flour were subjected to the addiction of NaOH and temperature variation experiments. Samples of starch (corn, cassava, HIPIX 100, HIPIX 101 and HIPIX 102 commercialized by Ingredion) and flour (cassava and potato) were tested. The starch samples were characterized through Scanning Electronic Microscopy and the amylose content were determined through spectrometry, swelling and solubility tests. The gelatinization was carried out through titration with NaOH, keeping the solution temperature constant at 40 oC. At the end of the tests, the optimal amount of NaOH consumed to gelatinize the starch or flour from different botanical sources was established and a correlation between the content of amylopectin in the starch and the starch/NaOH ratio needed for its gelatinization.

Keywords: froth flotation, gelatinization, sodium hydroxide, starches and flours

Procedia PDF Downloads 363
419 Effect of Different Microbial Strains on Biological Pretreatment of Sugarcane Bagasse for Enzymatic Hydrolysis

Authors: Achiraya Jiraprasertwong, Erdogan Gulari, Sumaeth Chavadej

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Among agricultural residues, sugarcane bagasse is one of the most convincing raw materials for the production of bioethanol due to its availability, and low cost through enzymatic hydrolysis and yeast fermentation. A pretreatment step is needed to enhance the enzymatic step. In this study, sugarcane bagasse (SCB), one of the most abundant agricultural residues in Thailand, was pretreated biologically with various microorganisms of white-rot fungus—Phanerochaete sordid (SK 7), Cellulomonas sp. (TISTR 784), and strain A 002 (Bacillus subtilis isolated from Thai higher termites). All samples with various microbial pretreatments were further hydrolyzed enzymatically by a commercial enzyme obtained from Aspergillus niger. The results showed that the pretreatment with the white-rot fungus gave the highest glucose concentration around two-fold higher when compared with the others.

Keywords: sugarcane bagasse, microorganisms, pretreatment, enzymatic hydrolysis

Procedia PDF Downloads 443
418 Study on Microbial Pretreatment for Enhancing Enzymatic Hydrolysis of Corncob

Authors: Kessara Seneesrisakul, Erdogan Gulari, Sumaeth Chavadej

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The complex structure of lignocellulose leads to great difficulties in converting it to fermentable sugars for the ethanol production. The major hydrolysis impediments are the crystallinity of cellulose and the lignin content. To improve the efficiency of enzymatic hydrolysis, microbial pretreatment of corncob was investigated using two bacterial strains of Bacillus subtilis A 002 and Cellulomonas sp. TISTR 784 (expected to break open the crystalline part of cellulose) and lignin-degrading fungus, Phanerochaete sordida SK7 (expected to remove lignin from lignocellulose). The microbial pretreatment was carried out with each strain under its optimum conditions. The pretreated corncob samples were further hydrolyzed to produce reducing glucose with low amounts of commercial cellulase (25 U•g-1 corncob) from Aspergillus niger. The corncob samples were determined for composition change by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscope (SEM). According to the results, the microbial pretreatment with fungus, P. sordida SK7 was the most effective for enhancing enzymatic hydrolysis, approximately, 40% improvement.

Keywords: corncob, enzymatic hydrolysis, glucose, microbial pretreatment

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417 Biogas Production Improve From Waste Activated Sludge Using Fenton Oxidation

Authors: A. Hassiba Zemmouri, B. Nabil Mameri, C. Hakim Lounici

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In this study, the effect of Fenton technology pretreatment on the anaerobic digestion of excess waste activated sludge (WAS) was investigated. The variation of physicochemical characteristics (TOC, DS, VSS, VS) and biogas volume (as form of value added products) were also evaluated. The preselected operator conditions of Fenton pretreatment were 0.01ml H2O2/g SS, 150 [H2O2]/[Fe2+], 25g/l TS, at 25 °C and 30, 60 and120 min as treatment duration. The main results show a Maximum solubilization and biodegradability (70%) obtained at 120 min of Fenton pretreatment duration. An increasing of TOC in soluble phase related obviously by releasing organic substances of sludge flocs was contested. Improving in biogas volume was also, increased. Fenton oxidation pretreatment may be a promising chemical pre-treatment for a benefic digestion, stabilization and volume reduction.

Keywords: waste activated sludge, fenton pre-treatment, biodegradability, biogas

Procedia PDF Downloads 640
416 Bee Colony Optimization Applied to the Bin Packing Problem

Authors: Kenza Aida Amara, Bachir Djebbar

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We treat the two-dimensional bin packing problem which involves packing a given set of rectangles into a minimum number of larger identical rectangles called bins. This combinatorial problem is NP-hard. We propose a pretreatment for the oriented version of the problem that allows the valorization of the lost areas in the bins and the reduction of the size problem. A heuristic method based on the strategy first-fit adapted to this problem is presented. We present an approach of resolution by bee colony optimization. Computational results express a comparison of the number of bins used with and without pretreatment.

Keywords: bee colony optimization, bin packing, heuristic algorithm, pretreatment

Procedia PDF Downloads 633
415 Synthesis of Na-LSX Zeolite and Hydrosodalite from Polish Fly Ashes

Authors: Barbara Bialecka, Zdzislaw Adamczyk, Magdalena Cempa

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In the work, the results of investigations into the hydrothermal zeolitization of fly ash from hard coal combustion in one of Polish Power Station have been presented. The chemical composition of the ash was determined by the method of X-ray fluorescence (XRF), whereas the phases of both fly ash and the products after synthesis were identified using microscopic observations, X-ray diffraction analysis (XRD) as well as electron scanning microscopy with measurements of the chemical compositions in micro areas (SEM/EDS). The synthesis was carried out with various concentrations of NaOH solution (3M, 4M and 6M) in the following conditions: synthesis temperature – 80ᵒC, synthesis time – 16 hours, volume of NaOH solution – 350ml, fly ash mass – 14g. The main chemical components of fly ash were SiO₂ and Al₂O₃, the contents of which reached 51.62 and 28.14%mas., respectively. The input ash contained mainly such phases as mullite, quarz, magnetite, and glass. The research results indicate that the phase composition of products after zeolitization was differentiated. The material after synthesis in 3M NaOH solution was found to contain mullite, quarz, magnetite, and Na-LSX zeolite. The products of synthesis in 4M NaOH solution were very similar to those in 3M solution (mullite, quarz, magnetite, Na-LSX zeolite), but they additionally contained hydrosodalite. The material after synthesis in 6M NaOH solution contains mullite, quarz, magnetite (similarly to synthesis in 3M and 4M NaOH solition) and additionally hydrosodalite. Therefore, the products of synthesis contain relic components from the fly ash input sample in the form of mullite, quarz, and magnetite, as well as new phases, which are Na-LSX zeolite and hydrosodalite. It should be noted that the products of synthesis in the case of 4M NaOH solution contained both new phases (Na-LSX zeolite and hydrosodalite), while the products from the extreme concentration of NaOH solutions (3M and 6M) contained only one of them. Observations in the scanning electron microscope revealed the new phases’ morphology. It was found that Na-LSX zeolite formed cubic crystals, whereas hydrosodalite formed characteristic aggregations. The results of investigations into the chemical composition in the micro area of phase grains in the products after synthesis reveal some dependencies, among others a characteristic increase in the content of sodium, related to the increased concentration of NaOH solution.

Keywords: Na-LSX, fly ash, hydrosodalite, zeolite

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414 Prevention of Cellulose and Hemicellulose Degradation on Fungal Pretreatment of Water Hyacinth Using Phanerochaete Chrysosporium

Authors: Eka Sari

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Potential degradation of cellulose and hemicellulose during the fungal pretreatment of lignocellulose has led to fermentable sugar yield will be low. This potential is even greater if the pretreatment of lignocellulosic that have low lignin such as water hyacinth. In order to prepare lignocellulose that have low lignin content, especially water hyacinth efforts are needed to prevent the degradation of cellulose and cellulose. One attempt to prevent the degradation of cellulose and hemicellulose is to replace the substrate needed by the addition of a simple carbon compounds such as glucose. Glucose sources used in this study is molasses. The purpose of this research to get the right of concentration of molasses to reduce the degradation of cellulose and hemicellulose during the pretreatment process and obtain fermentable sugar yields on high. The results showed that the addition of molasses with a concentration of 2% is able to reduce the degradation of cellulose from 25.53% to 10% and hemicellulose degradation of 20.12% to 10.89%. Fermentable sugar yields produced only reached 43.91%. To improve the yield of glucose is then performed additional combonation of molasses of 2% molasses and co-factor Mn2+ 0.5%. Fermentable sugar yield increased to 67.66% and the degradation of cellulose and hemicellulose decreased to 2.44% and 2.71%, respectively.

Keywords: water hyacinth, cellulose, hemicelulose, degradation, pretreatment, fungus

Procedia PDF Downloads 557
413 Evaluation of Microwave-Assisted Pretreatment for Spent Coffee Grounds

Authors: Shady S. Hassan, Brijesh K. Tiwari, Gwilym A. Williams, Amit K. Jaiswal

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Waste materials from a wide range of agro-industrial processes may be used as substrates for microbial growth, and subsequently the production of a range of high value products and bioenergy. In addition, utilization of these agro-residues in bioprocesses has the dual advantage of providing alternative substrates, as well as solving their disposal problems. Spent coffee grounds (SCG) are a by-product (45%) of coffee processing. SCG is a lignocellulosic material, which is composed mainly of cellulose, hemicelluloses, and lignin. Thus, a pretreatment process is required to facilitate an efficient enzymatic hydrolysis of such carbohydrates. In this context, microwave pretreatment of lignocellulosic biomass without the addition of harsh chemicals represents a green technology. Moreover, microwave treatment has a high heating efficiency and is easy to implement. Thus, microwave pretreatment of SCG without adding of harsh chemicals investigated as a green technology to enhance enzyme hydrolysis. In the present work, microwave pretreatment experiments were conducted on SCG at varying power levels (100, 250, 440, 600, and 1000 W) for 60 s. By increasing microwave power to a certain level (which vary by varying biomass), reducing sugar increases, then reducing sugar from biomass start to decrease with microwave power increase beyond this level. Microwave pretreatment of SCG at 60s followed by enzymatic hydrolysis resulted in total reducing sugars of 91.6 ± 7.0 mg/g of biomass (at microwave power of 100 w). Fourier transform Infrared Spectroscopy (FTIR) was employed to investigate changes in functional groups of biomass after pretreatment, while high-performance liquid chromatography (HPLC) was employed for determination of glucose. Pretreatment of lignocellulose using microwave was found to be an effective and energy efficient technology to improve saccharification and glucose yield. Energy performance will be evaluated for the microwave pretreatment, and the enzyme hydrolysate will be used as media component substitute for the production of ethanol and other high value products.

Keywords: lignocellulose, microwave, pretreatment, spent coffee grounds

Procedia PDF Downloads 419
412 Screening and Optimization of Pretreatments for Rice Straw and Their Utilization for Bioethanol Production Using Developed Yeast Strain

Authors: Ganesh Dattatraya Saratale, Min Kyu Oh

Abstract:

Rice straw is one of the most abundant lignocellulosic waste materials and its annual production is about 731 Mt in the world. This study treats the subject of effective utilization of this waste biomass for biofuels production. We have showed a comparative assessment of numerous pretreatment strategies for rice straw, comprising of major physical, chemical and physicochemical methods. Among the different methods employed for pretreatment alkaline pretreatment in combination with sodium chlorite/acetic acid delignification found efficient pretreatment with significant improvement in the enzymatic digestibility of rice straw. A cellulase dose of 20 filter paper units (FPU) released a maximum 63.21 g/L of reducing sugar with 94.45% hydrolysis yield and 64.64% glucose yield from rice straw, respectively. The effects of different pretreatment methods on biomass structure and complexity were investigated by FTIR, XRD and SEM analytical techniques. Finally the enzymatic hydrolysate of rice straw was used for ethanol production using developed Saccharomyces cerevisiae SR8. The developed yeast strain enabled efficient fermentation of xylose and glucose and produced higher ethanol production. Thus development of bioethanol production from lignocellulosic waste biomass is generic, applicable methodology and have great implication for using ‘green raw materials’ and producing ‘green products’ much needed today.

Keywords: rice straw, pretreatment, enzymatic hydrolysis, FPU, Saccharomyces cerevisiae SR8, ethanol fermentation

Procedia PDF Downloads 537
411 Pineapple Waste Valorization through Biogas Production: Effect of Substrate Concentration and Microwave Pretreatment

Authors: Khamdan Cahyari, Pratikno Hidayat

Abstract:

Indonesia has produced more than 1.8 million ton pineapple fruit in 2013 of which turned into waste due to industrial processing, deterioration and low qualities. It was estimated that this waste accounted for more than 40 percent of harvested fruits. In addition, pineapple leaves were one of biomass waste from pineapple farming land, which contributed even higher percentages. Most of the waste was only dumped into landfill area without proper pretreatment causing severe environmental problem. This research was meant to valorize the pineapple waste for producing renewable energy source of biogas through mesophilic (30℃) anaerobic digestion process. Especially, it was aimed to investigate effect of substrate concentration of pineapple fruit waste i.e. peel, core as well as effect of microwave pretreatment of pineapple leaves waste. The concentration of substrate was set at value 12, 24 and 36 g VS/liter culture whereas 800-Watt microwave pretreatment conducted at 2 and 5 minutes. It was noticed that optimum biogas production obtained at concentration 24 g VS/l with biogas yield 0.649 liter/g VS (45%v CH4) whereas microwave pretreatment at 2 minutes duration performed better compare to 5 minutes due to shorter exposure of microwave heat. This results suggested that valorization of pineapple waste could be carried out through biogas production at the aforementioned process condition. Application of this method is able to both reduce the environmental problem of the waste and produce renewable energy source of biogas to fulfill local energy demand of pineapple farming areas.

Keywords: pineapple waste, substrate concentration, microwave pretreatment, biogas, anaerobic digestion

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410 Sustainable Dyeing of Cotton and Polyester Blend Fabric without Reduction Clearing

Authors: Mohammad Tofayel Ahmed, Seung Kook An

Abstract:

In contemporary research world, focus is more set on sustainable products and innovative processes. The global textile industries are putting tremendous effort to achieve a balance between economic development and ecological protection concurrently. The conservation of water sources and environment have become immensely significant issue in textile dyeing production. Accordingly, an attempt has been taken in this study to develop a process to dye polyester blend cotton without reduction clearing process and any extra wash off chemical by simple modification aiming at cost reduction and sustainability. A widely used combination of 60/40 cotton/polyester (c/p) single jersey knitted fabric of 30’s, 180 g/m² was considered for study. Traditionally, pretreatment is done followed by polyester part dyeing, reduction clearing and cotton part dyeing for c/p blend dyeing. But in this study, polyester part is dyed right away followed by pretreatment process and cotton part dyeing by skipping the reduction clearing process diametrically. The dyed samples of both traditional and modified samples were scrutinized by various color fastness tests, dyeing parameters and by consumption of water, steam, power, process time and total batch cost. The modified process in this study showed no necessity of reduction clearing process for polyester blend cotton dyeing. The key issue contributing to avoid the reduction clearing after polyester part dyeing has been the multifunctional effect of NaOH and H₂O₂ while pretreatment of cotton after polyester part dyeing. The results also revealed that the modified process could reduce the consumption of water, steam, power, time and cost remarkably. The bulk trial of modified process demonstrated the well exploitability to dye polyester blend cotton substrate ensuring all fastness and dyeing properties regardless of dyes category, blend ratio, color, and shade percentage thus making the process sustainable, eco-friendly and economical. Furthermore, the proposed method could be applicable to any cellulosic blend with polyester.

Keywords: cotton, dyeing, economical, polyester

Procedia PDF Downloads 188
409 Effect of N2 Pretreatment on the Properties of Tungsten Based Catalysts in Metathesis of Ethylene and 2-Butene

Authors: Kriangkrai Aranyarat

Abstract:

The effect of N2 pretreatment on the catalytic activity of tungsten-based catalysts was investigated in the metathesis of ethylene and trans-2-butene at 450oC and atmospheric pressure. The presence of tungsten active species was confirmed by UV-Vis and Raman spectroscopy. Compared to the WO3-based catalysts treated in air, higher amount of WO42- tetrahedral species and lower amount of WO3 crystalline species were observed on the N2-treated ones. These contribute to the higher conversion of 2-butene and propylene selectivity during 10 h time-on-stream. Moreover, N2 treatment led to lower amount of coke formation as revealed by TPO of the spent catalysts.

Keywords: metathesis, pretreatment, propylene, tungsten

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408 Fermentation of Wood Waste by Treating with H₃PO₄-Acetone for Bioethanol Production

Authors: Deokyeong Choe, Keonwook Nam, Young Hoon Roh

Abstract:

Wood waste is a potentially significant resource for economic and environment-friendly recycling. Wood waste represents a key sustainable source of biomass for transformation into bioethanol. Unfortunately, wood waste is highly recalcitrant for biotransformation, which limits its use and prevents economically viable conversion into bioethanol. As a result, an effective pretreatment is necessary to degrade cellulose of the wood waste, which improves the accessibility of cellulase. In this work, a H₃PO₄-acetone pretreatment was selected among the various pretreatment methods and used to dissolve cellulose and lignin. When the H₃PO₄ and acetone were used, 5–6% of the wood waste was found to be very appropriate for saccharification. Also, when the enzymatic saccharification was conducted in the mixture of the wood waste and 0.05 M citrate buffer solution, glucose and xylose were measured to be 80.2 g/L and 9.2 g/L respectively. Furthermore, ethanol obtained after 70 h of fermentation by S. cerevisiae was 30.4 g/L. As a result, the conversion yield from wood waste to bioethanol was calculated to be 57.4%. These results show that the pretreated wood waste can be used as good feedstocks for bioethanol production and that the H₃PO₄-acetone pretreatment can effectively increase the yield of ethanol production.

Keywords: wood waste, H₃PO₄-acetone, bioethanol, fermentation

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407 An Efficient Hybrid Feedstock Pretreatment Technique for the Release of Fermentable Sugar from Cassava Peels for Biofuel Production

Authors: Gabriel Sanjo Aruwajoye, E. B. Gueguim Kana

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Agricultural residues present a low-cost feedstock for bioenergy production around the world. Cassava peels waste are rich in organic molecules that can be readily converted to value added products such as biomaterials and biofuels. However, due to the presence of high proportion of structural carbohydrates and lignin, the hydrolysis of this feedstock is imperative to achieve maximum substrate utilization and energy yield. This study model and optimises the release of Fermentable Sugar (FS) from cassava peels waste using the Response Surface Methodology. The investigated pretreatment input parameters consisted of soaking temperature (oC), soaking time (hours), autoclave duration (minutes), acid concentration (% v/v), substrate solid loading (% w/v) within the range of 30 to 70, 0 to 24, 5 to 20, 0 to 5 and 2 to 10 respectively. The Box-Behnken design was used to generate 46 experimental runs which were investigated for FS release. The obtained data were used to fit a quadratic model. A coefficient of determination of 0.87 and F value of 8.73 was obtained indicating the good fitness of the model. The predicted optimum pretreatment conditions were 69.62 oC soaking temperature, 2.57 hours soaking duration, 5 minutes autoclave duration, 3.68 % v/v HCl and 9.65 % w/v solid loading corresponding to FS yield of 91.83g/l (0.92 g/g cassava peels) thus 58% improvement on the non-optimised pretreatment. Our findings demonstrate an efficient pretreatment model for fermentable sugar release from cassava peels waste for various bioprocesses.

Keywords: feedstock pretreatment, cassava peels, fermentable sugar, response surface methodology

Procedia PDF Downloads 366
406 The Comparison and Optimization of the Analytic Method for Canthaxanthin, Food Colorants

Authors: Hee-Jae Suh, Kyung-Su Kim, Min-Ji Kim, Yeon-Seong Jeong, Ok-Hwan Lee, Jae-Wook Shin, Hyang-Sook Chun, Chan Lee

Abstract:

Canthaxanthin is keto-carotenoid produced from beta-carotene and it has been approved to be used in many countries as a food coloring agent. Canthaxanthin has been analyzed using High Performance Liquid Chromatography (HPLC) system with various ways of pretreatment methods. Four official methods for verification of canthaxanthin at FSA (UK), AOAC (US), EFSA (EU) and MHLW (Japan) were compared to improve its analytical and the pretreatment method. The Linearity, the limit of detection (LOD), the limit of quantification (LOQ), the accuracy, the precision and the recovery ratio were determined from each method with modification in pretreatment method. All HPLC methods exhibited correlation coefficients of calibration curves for canthaxanthin as 0.9999. The analysis methods from FSA, AOAC, and MLHW showed the LOD of 0.395 ppm, 0.105 ppm, and 0.084 ppm, and the LOQ of 1.196 ppm, 0.318 ppm, 0.254 ppm, respectively. Among tested methods, HPLC method of MHLW with modification in pretreatments was finally selected for the analysis of canthaxanthin in lab, because it exhibited the resolution factor of 4.0 and the selectivity of 1.30. This analysis method showed a correlation coefficients value of 0.9999 and the lowest LOD and LOQ. Furthermore, the precision ratio was lower than 1 and the accuracy was almost 100%. The method presented the recovery ratio of 90-110% with modification in pretreatment method. The cross-validation of coefficient variation was 5 or less among tested three institutions in Korea.

Keywords: analytic method, canthaxanthin, food colorants, pretreatment method

Procedia PDF Downloads 683