Conversion Of Bagasse Research Articles

Exploring bioenergy prospects from malt bagasse: Insights through pyrolysis with multi-component kinetic analysis and thermodynamic parameter estimation

Malt bagasse is a by-product of little commercial value in the brewing industry. Under this scenario, the current study represents the first investigation aiming to determine the kinetic triplet and thermodynamic parameters for malt bagasse pyrolysis using a multi-component kinetic approach to elucidate its bioenergy prospects. The pyrolysis progress profiles of malt bagasse were obtained through slow pyrolysis experiments on a thermogravimetric scale in an inert atmosphere, employing four distinct heating rates (10, 15, 25, and 40 °C min−1). This investigation also used the Frazer-Suzuki deconvolution function to elucidate the relative contributions of hemicellulose, cellulose, and lignin to malt bagasse pyrolysis. Activation energies for devolatilization reactions were determined by the isoconversional methods of Friedman, Flynn-Wall-Ozawa, Kissinger-Akahira-Sunose, and Starink, and revealed the lowest and highest mean values for pseudo-hemicelluloses (158.3−215.3 kJ mol−1) and pseudo-lignin (279.5−294.8 kJ mol−1), respectively. Frequency factors in malt bagasse pyrolysis ranging from 8.9 × 1016 and 2.2 × 1023 min−1 offer evidence of a simplified reaction chemistry pathway in the conversion towards bioenergy production. The integral master plot indicates the involvement of order-based and geometrical contraction-based mechanisms in malt bagasse pyrolysis. After defining multiple kinetic triplets, a differential equation encompassing contributions from all pseudo-components was formulated, and the simulated results aligned closely with experimental data, accurately describing pyrolysis progress profiles with at least 92.8% precision. The thermodynamic analysis reveals positive ΔH and ΔG values, indicating the non-spontaneous nature of malt bagasse pyrolysis. Higher disorder in the resultant products is attributed to volatile release and molecular rearrangement and is signified by positive ΔS values compared to the initial reactants. This study provided valuable insights into the valorization of malt bagasse, offering crucial information for optimizing pyrolysis reactors, scaling, and designing malt bagasse conversion into valuable biofuels, constituting an effort towards bio-circular economy principles based on the zero-waste concept.

Ionic liquid and diluted sulfuric acid combinatorial pretreatment for efficient sugarcane bagasse conversion to L-lactic acid

An economical pretreatment method is needed to produce the L-lactic acid from renewable biomass. Six different combinatorial experiments including choline chloride [Ch][Cl], 1-ethyl-3-methylimidazolium chloride [Emim][Cl], and 1-butyl-3-methylimidazolium chloride [Bmim][Cl], diluted acid sulfuric acid (DSA), and two ionic liquids (ILs) were tested. Ionic liquid (ILs) step performed at 90, 110, and 130 °C. The cellulose content of sugarcane bagasse (SCB) increased from 42.1 % (raw material) to 74.6 % (combinatorial pretreatment with DSA and [Emim][Cl]) to 79.9 % (after water washing). Pretreated SCB was employed in enzymatic saccharification and L-lactic acid fermentation. Enzymatic hydrolysis resulted in the maximal levels of glucose titer (220.7 g/L) and yield (73.5 %). L-lactic acid concentration reached to 204.1 g/L when SCB fermented with Lactobacillus casei ATCC 334 at a 25 % w/w solid loading. The two-step pretreatment SCB underwent morphological changes, as evidenced by FTIR, XRD, and SEM analyses. High cellulose levels and high lactic acid highlight the advantages on energy efficiency of a two-step combined pretreatment procedure over a standard single-step pretreatment technique.

Optimization of Sugarcane Bagasse Conversion Technologies Using Process Network Synthesis Coupled with Machine Learning

Sugarcane bagasse is a commonly generated item from the food industry in the world—the amount of sugarcane bagasse production is increasing yearly. In 2017, the reported sugarcane production in Malaysia was 30,000 kg, which resulted in 9,800 kg of sugarcane bagasse. Sugarcane bagasse produces steam as waste management in Malaysia or simply in landfills. This study aims to optimize sugarcane bagasse conversion technologies using process network synthesis. A superstructure of sugarcane bagasse was created via P-Graph, with multiple pathways or processes being considered. Data needed for the sustainability assessment of each pathway was acquired from various journal sources, including conversion fraction, operating and capital cost, greenhouse gas emission, and the selling price of products were implemented into the superstructure. Then, the data from the feasible structure generated would be analyzed using machine learning via Waikato Environment for Knowledge Analysis software. The data sets were analyzed using this software using the selected algorithm as P-graph developed 17 feasible solution structures. All 17 generated solution structures were analyzed using six different classifier algorithms. The multilayer perceptron algorithm had the best and the least error in classifying the data. Hence, the multilayer perceptron algorithm proved that the correlation between products produced from sugarcane bagasse and the profitability of the process was significant. Therefore, the model can be a basis for determining the best process for sugarcane bagasse conversion technologies.

Precise in-situ infrared spectra and kinetic analysis of gasification under the H2O or CO2 atmospheres

Studying the mechanisms of bagasse conversion into syngas is essential to sustain the growing use of biomass in energy economy production. In this work, the precise kinetics of bagasse gasification with various gasification agents was firstly investigated employing in-situ infrared spectra with Coats-Redfern integration, combining qualitative infrared spectroscopy allowed for kinetic analysis, so as to explore how the intermediate species vary in each basic reaction. The results demonstrate that the CO2 agent reduces the activation energy of nitryl after amino oxidation, making the lignin involved in gasification more easily as well as causing higher gasification efficiency. On the one hand, steam serving as a gasification agent enhances the concentration of hydroxyl groups and produces H2-rich syngas. On the other hand, the strong oxidizing hydroxyl group reduces the energy barrier of carbonyl and carboxyl groups in cellulose, which facilitates the gasification process. Furthermore, this study compared the effects of gasification agent (H2O or CO2) on syngas composition, reactor temperature distribution, carbon conversion rate, gasification efficiency, as well as low calorific value, providing essential information for understanding the micro-reaction pathways and pathway regulation during bagasse gasification.

Modeling of sugarcane bagasse conversion to levulinic acid using response surface methodology (RSM), artificial neural networks (ANN), and fuzzy inference system (FIS): A comparative evaluation

Levulinic acid is recognized as a prominent value-added chemical that can be obtained from bioresources and has versatile industrial applications. This work reports bioprocess modeling of levulinic acid synthesis from sugarcane bagasse employing response surface methodology and artificial intelligence techniques, including artificial neural network and fuzzy inference system approaches. The influence of process parameters, namely reaction temperature, concentration of levulinic acid and reaction time on the production of levulinic acid was investigated. The levulinic acid production values predicted by empirical models were compared with experimentally acquired data. The predictive capability of various models was appraised by computing statistical indices. The artificial neural network model was determined to be the best predictive model with the highest coefficient of determination value of 0.96 and the lowest error values (root mean square error = 0.272, mean absolute error = 0.072 and mean absolute percentage deviation = 2 %). The feedforward back propagation network with 3–10-1 architecture was employed to model the production of levulinic acid. The process optimization was performed using the desirability function approach. The bagasse, on treatment under optimum conditions, with 1 M sulphuric acid at 190 °C for 15 min yielded 5.40 mg/mL levulinic acid accounting for 77.1 % process efficiency. The utilization of waste biomass sugarcane bagasse would offer a sustainable approach for the production of platform chemical levulinic acid.

Economic and environmental sustainability assessment of guayule bagasse to fuel pathways

Guayule (Parthenium argentatum A. Gray) is a desert-dwelling crop that can produce hard rubber for tires and has the potential to help meet the water conservation needs of arid regions such as the Southwest U.S. Previous work has quantified the cost and environmental impact from guayule rubber production. However, establishing the economic viability of a domestic guayule industry requires identifying value-added products from the residual non-rubber guayule biomass, referred to as bagasse. Using guayule bagasse for bioenergy production is one potential solution, but the best pathway for thermochemical conversion of bagasse to fuels has yet to be defined. In this work, process models of pyrolysis and pelletization of bagasse are developed to inform a path to commercialization. A facility processing 200 tonnes of guayule bagasse per day is considered with a system boundary defined from biomass cultivation to fuel combustion. The materials and energy inventory results enabled the first comparative assessment of bagasse to fuels by concurrently performing techno-economic analysis and well-to-wheels life cycle assessment on both pathways. The minimum fuel selling price for the bagasse to fuels pathway was $0.076 per MJ ($9.26 per gallon of gasoline equivalent) and the minimum selling price of pellets from bagasse was $176 per tonne. This work compares the economic and life cycle results of both processes to make conclusions about the economic potential of bagasse and environmental impact of its conversion, areas to reduce production cost of biofuels, and potential for greenhouse gas emissions reduction compared with conventional fuels. In addition, the work identifies areas where future research may optimize production costs such that these fuels can be integrated alongside guayule rubber into a successful bioeconomy for the Southwest United States.

English

Large quantities of bagasse are regularly accumulated on open spaces around sugar factory thereby endangering fragile ecosystem. The sugar cane bagasse carbonization process can be put into effect as an environmentally friendly, energy self-providing continuous flow technology. Therefore, the objective of this study was to use bagasse for the production of high caloric value briquette to safeguard the environment from pollution. Bagasse sample was collected from Wonje sugar factory and carbonized in an oxygen deficient environment at Ethiopian Rural Energy Development and Dissemination Center Laboratory, Addis Ababa. The carbonized materials were mixed with clay and molasses as a binder in different ratio to make a briquette using briquette extruder machine. Caloric value of the briquettes produced from bagasse using clay and molasses as a binder in different ratio ranged between 3,529-4,064 and 3,964-4,442 cal/g, respectively. The highest caloric value using clay as a binder was in the ratio 20:80 and the lowest caloric value using molasses as a binder was in the ration 25:75. Further analysis showed that through conversion of bagasse from Wonji sugar factory into briquette, annually the factory could generate 3.1×10-10 cal of energy and substitutes 13.01 m3 of firewood or save 0.13 to 0.16 ha of tropical forests from deforestation and have the potential to sequestrate 17.90 to 22.03 tons of carbon annually. Further, the study concluded that briquettes produced from bagasse could be used as a quality source of energy and bagasse waste management option around sugar industry.   Key words:  Energy, briquette, carbon sequestration, caloric value.

Simultaneous thermal liquefaction of sugarcane bagasse and esterification with ethanol and fusel oil: One-Step process for biofuel production

Sugarcane bagasse is an abundant residue from the ethanol/sugar industries and its liquefaction can be a low-cost process for the production of liquid biofuels. However, the resulting biocrude has high acidity, which requires an upgrading before being used. In this study, ethanol and fusel oil, which is the heavy residue of ethanol distillation made up of higher alcohols, were used as solvents for the liquefaction of bagasse. The 1:10 biomass:solvent ratio mixture was used at 300 °C for 30 min and (10 bar) N2 atmosphere. A mixture of both solvents was also tested to make a comparative study. The process with ethanol showed 72% bagasse conversion, but the best result showed 91% with fusel oil, producing a low biochar content (9%). After the distillation of the liquid product, a biocrude with high combustion heat (30.6 MJ.kg−1) and rich in esters was obtained. The results of GC/MS revealed the greater presence of esters with substituted isoamyl groups (51.2%) and, to a lesser extent, phenolic compounds (2.5%). The biochar has a higher heating value of 30 MJ.kg−1 and special thermal stability, suitable for application as a solid fuel. The biocrude was mixed with marine diesel (5%) and the properties of the mixture were evaluated, without relevant modifications. This innovative process showed the use of two residues, bagasse, and fusel oil, to produce a biofuel to be used with different types of diesel, with economic and environmental gains in a cycle economy for the ethanol industry.

Residual sugarcane bagasse conversion in India: current status, technologies, and policies

The Indian sugar industry’s growth and residual lignocellulosic sugarcane bagasse (RSB) generation rate are complementary to each other. It is estimated that over 75–90 million tonnes of wet RSB are produced annually from 600 operational sugar mills in India. Therefore, the efficient utilization of residual bagasse needs immediate attention from sugar industries and the scientific community worldwide. Albeit recently developed technologies have shown promising prospects for the sustainable conversion of RSB into fuels and value-added chemicals, there is an apparent lack of consensus among the scientific community on technical understanding and commercial applicability of current RSB conversion technologies. This review discusses applications of RSB in Indian industries for electricity generation, concrete manufacturing from RSB ash, nanocomposite production, as well as pulp and paper, furfural, furfuryl alcohol, bioethanol, and value-added chemical production. Besides, the conversion of RSB major component lignin to fuel and high-value specialty chemicals has been discussed. Moreover, the government of India policies and subsequent revisions in 2018 to promote biomass and RSB conversion technologies has been presented. Subsequently, major challenges associated with the implementation of different conversion technologies have been explored. Overall, it is observed that there is a huge opportunity in India to utilize the RSB for value-added chemicals production, pulp, and paper production, electricity generation, and other applications. Nevertheless, the Government of India current policies directed towards promoting the RSB uses primarily for electricity production via cogenerations.

Bioethanol Production from Sugarcane Bagasse Using <em>Neurospora intermedia </em>in an Airlift Bioreactor

Bagasse as solid waste in sugarcane industry can be utilized as one of the potential raw materials in the bioprocess industry. This research aims to investigate the conversion of bagasse to bioethanol using simultaneous saccharification and fermentation in an airlift bioreactor. Neurospora intermedia was used as a biological agent that carried out the saccharification and fermentation of sugarcane bagasse simultaneously for bioethanol production. Cell morphology of N. intermedia in the form of pellet was required to provide free movement in the axial flow of airlift bioreactor. The medium pH strongly affects the morphological shape of N. intermedia. Therefore, the formation of good pellets of inoculum was observed under acidic conditions, i.e. pH 3.0 – 3.5. The effect of the initial concentration of nutrient on the inoculum growth was also investigated. Inoculums cultured in potato dextrose broth (PDB) medium with a half the strength of the common nutrient concentration of PDB qualitatively indicated good growth in terms of the size and density of cells. The inoculums with good morphological form were fed into the airlift bioreactor, which already contained a liquid medium with initial pH of 3.5 and also contained pre-treated bagasse. In experiments using the airlift bioreactor, the pre-treated bagasse was added to various nutrient concentrations of the PDB infusion medium. The highest bioethanol production from bagasse was monitored in the medium culture of half strength PDB infusion. The yield of bioethanol obtained from total sugarcane bagasse and PDB in an air lift bioreactor achieved approximately 40%, which has an infusion medium with a half-strength PDB and initial pH of 3.0.

Synthesis of 5-HMF from an ultrasound-ionic liquid pretreated sugarcane bagasse by using a microwave-solid acid/ionic liquid system

This work aimed at investigating the synthesis of 5-HMF from the ultrasound-ionic liquid pretreated sugarcane bagasse in a microwave-solid acid-ionic liquid system. The XRD analysis indicated that the macrostructure of cellulose remained intact after the ultrasound-ionic pretreatment, [Bmim]OAc showed better performance than [Bmim]Cl. The best conditions for the untreated bagasse conversion to 5-HMF were [Bmim]OAc, ion-exchange resin catalyst, D001-cc, 140 ℃ and 25 min. The ultrasound-ionic liquid pretreatment at different frequencies (20–50 kHz) increased the 5-HMF yield by 39.73–165.43 % compared with that of the untreated bagasse, indicating the role of the acoustic cavitation in enhancing the transformation of bagasse into 5-HMF. The bagasse pretreated with [Bmim]OAc/ultrasound at 40 kHz/30 min showed the highest yield of 5-HMF (65.72 %). The synthesis of 5-HMF from the pretreated sugarcane bagasse in the microwave-solid acid/ionic liquid system could be a promising channel for production of biofuels and related chemicals.

Morphoagronomic and industrial performance of cassava (<i>Manihot esculenta</i> Crantz) germplasm for the production of starch and solid byproducts

The objective of the present research work was to study the morphoagronomic and industrial performance of three cassava clones. The study was carried out in two stages: A) the MMEXV5, MMEXV40, and MMEXCH23 clones were established in a subhumid warm climate; B) the storage roots were processed. For the first essay, a randomized complete block design was used, while for the second essay, a completely randomized design was used. An ANOVA analysis was done, as well as a means comparison (Tukey, 0.05) and a Principal Component Analysis (PCA). The ANOVA showed differences in the evaluated traits (p ≤ 0.05). The MMEXV5 clone showed high storage roots yield (RY = 41.24 t ha-1), plant height (PH = 4.79 m), and pulp (PUL = 80.58%); MMEXCH23 achieved higher contents of bagasse and peel; while, MMEXV40 had the highest total starch extraction (STL = 12.57%). Additionally, the three clones reached high dry matter content (DM = 34.22 to 38%), trait considered a quality factor. The PCA showed that RY was associated with a higher number of storage roots generated, PH, PUL, and lobe dimensions; but, the clones with high RY and PH developed poor DM and yield of starch extraction. Finally, the valorization of the evaluated germplasm could make cassava into the basic raw material in a great variety of products with high added value for the food and non-food industry, even obtain bioproducts and bioenergy through the conversion of bagasse and peel.

Nitrogen Content and Use Efficiency of Sweet Sorghum Grown in the Lower Midwest

Optimizing N fertilizer inputs is imperative for improving sweet sorghum [Sorghum bicolor (L.) Moench] yields and biofuel feedstock system efficiency. A 2‐yr study was conducted to determine the physiological N‐use efficiency (NUE) response in sweet sorghum's ethanol yield of stem juice, bagasse, and total ethanol yield (TEY). Two sweet sorghum cultivars (‘Dale’ and ‘Top 76–6’) were fertilized at five N fertilizer rates (0, 56, 112, 168, and 224 kg ha−1). At harvest, the stem juice and bagasse yields were measured then analyzed for the corresponding N concentrations and N contents. Whole‐plant N recovery efficiency ranged from −1.5 to 57.6% across both years, with a significant N rate effect only in one study year. The NUE of juice ethanol yield only demonstrated an N response in the second year, whereas the NUE of lignocellulosic ethanol yield was greatest at the 56 kg ha−1 fertilizer rate each year. The NUE of total theoretical ethanol yield, determined as the sum of juice and bagasse conversion to ethanol, averaged 169 L EtOH kg−1 N across both years and was greatest at the 56 kg N ha−1 fertilizer rate in both years, and decreased at N rates exceeding 56 kg ha−1 in only one of the years. This study revealed that although sweet sorghum ethanol yields increased with N fertilizer application, NUE was greatest with low N fertilizer rates, consistent with previous research indicating that sweet sorghum is an appropriate biofuel feedstock for production in low‐input systems or on marginal lands.Core Ideas Nitrogen recovery and use efficiencies of sweet sorghum juice and bagasse were measured for two years in Missouri. Nitrogen recovery efficiency was greatest in one study year when 224 kg N ha−1 was applied, with no differences in recovery in the second year. The N use efficiency of estimated total ethanol yield was greatest at 56 kg N ha−1.

Clean and effective catalytic hydrolysis of bagasse waste to small-molecular compounds over a hydrothermally stable Ru/La(OH)3

Ruthenium/lanthanum hydroxide (Ru/La(OH)3), a hydrothermally stable catalyst, was prepared and used for catalyzing hydrolysis of bagasse, a sugar industry waste, to small-molecular compounds under low initial H2 pressure (IHP 0.2 MPa, 5% H2 in 4 MPa H2 and N2 mixture) at 240 °C. Neither oligomers nor char was formed and bagasse was almost completely converted into soluble portion (SPCH, 59.1 wt%) and gaseous products by the catalytic hydrolysis (CH). Obviously different from the methanol-soluble portion and ethanol-soluble portion from the bagasse methanolysis and ethanolysis, in total 104 organic compounds were detected in SPCH, among which alkyl-substituted phenols & benzenepolyols (38.8%), alkoxy-substituted phenols (22.2%), ketones (15.1%), and carboxylic acids (12.2%) are dominant according to the analysis with a gas chromatograph/mass spectrometer (GC/MS). Based on the analysis with a quadrupole exactive orbitrap mass spectrometer, heteroatom-containing compounds, especially oxygenates, are predominant in the SPs, while more species including smaller molecular fragments, can be identified in SPCH, which is consistent with the analysis with GC/MS. In addition, the catalytic hydroconversion of phenethoxybenzene over Ru/La(OH)3 further confirms that appropriately raising the temperature and reducing the IHP facilitate the formation and transfer of active H∙. In one-pot, clean and effective conversion of bagasse with low H2 consumption and in a green solvent can be achieved through this strategy.

Numerical Modeling of Mass Loss and Temperature Profiles in the Thermal Decomposition of Bagasse in a Fixed Rectangular Oven

This work deals with the numerical study of the pyrolysis process in the thermochemical conversion of bagasse in an inert atmosphere and a two-dimensional numerical code (2D) of the reactions involved in the pyrolysis of bagasse of the sugarcane located in Morocco. The finite difference and the Range-Kutta method of second order have been used to simulate the pyrolysis of bagasse in a fixed rectangular oven of the bagasse. Transport modeling is made using homogenized equations at the Darcy scale. The thermal imbalance between the solid and the gas phase under the implementation of a temperature model of two fields has been revealed by previous studies, one for gas and one for solid. During this study, the aim has been to model the degradation of bagasse by pyrolysis. It is a very complex phenomenon that usually precedes the stage of heterogeneous combustion. The results provided by the numerical code developed are almost in agreement with the ones obtained by the experimental study presented in literature. This code is quite flexible; it can take into account different boundary conditions and allows changing easily the order of spatial discretization.

Comparison of different pretreatment methods for efficient conversion of bagasse into ethanol

ABSTRACTBiofuel production is popular with biotechnologists due to the continuously increasing need for energy. One major issue is to get maximum fuel production for minimum cost. In our studies we focused on both factors and developed a method for bioethanol production by investing in low cost chemicals. We compared three chemical pretreatments (NaOH, Na2SO3 and H2O2) at 121°C temperature and 15 psi pressure for delignification to evaluate the efficacy of chemicals in pretreatment. NaOH and Na2SO3 showed comparable percentage delignification (81.3 and 80.17% respectively) while H2O2 showed 67.4% delignification. Endogenously produced cellulolytic enzyme with 30 IU/mL CMCase and 22 IU/mL FPase units was used for saccharification of exposed cellulose. An indigenously developed strain of Saccharomyces cerevisiae SC36 (developed in a peptone free high gravity media) was used to ferment saccharified sugars into ethanol at 37°C fermentation temperature. We were able to convert 27% of the total bagasse (as per dry mass basis) into ethanol with NaOH pretreatment followed by 26% bagasse (as per dry mass basis) into ethanol with Na2SO3 pretreatment and 1% ethanol was obtained from H2O2 treated bagasse.

Steam reforming of bagasse to hydrogen and synthesis gas using ruthenium promoted Ni[sbnd]Fe/γ[sbnd]Al2O3nano-catalysts

Bagasse conversion to H2, CO and light gaseous hydrocarbons was performed in a batch micro reactor under 850 °C and atmospheric pressure in the presence of unpromoted and ruthenium promoted NiFe/γAl2O3 nano catalysts. The nano catalysts were prepared with 12 wt.% Ni, 6 wt.% Fe and 0.5 to 2 wt.% Ru loadings via microemulsion technique. The catalysts were extensively characterized using ICP, XRD, TPR, BET, TEM and H2 chemisorption techniques. XRD patterns confirmed formation of NiFe alloys on the catalysts. Ruthenium increased dispersion of active metal clusters by 44.6% and consequently improved the reducibility of the catalysts. The addition of 1 wt.% Ru increased the total gas yield, the yield of hydrogen, the yield of carbon monoxide and the carbon conversion efficiency by 34.2%, 35.9%, 33.54% and 44% respectively.

Production of high-pure xylooligosaccharides from sugarcane bagasse using crude β-xylosidase-free xylanase of Bacillus subtilis KCX006 and their bifidogenic function

Xylooligosaccharides (XOS) are used as prebiotics in food industries. XOS with high purity is required for effective prebiotic function. All crude xylanases exhibit β-xylosidase, which forms significant amount of xylose and reduces the yield and purity of XOS. Here, we describe the use of crude xylanase of Bacillus subtilis devoid of β-xylosidase to produce high-pure XOS from ammonia pretreated sugarcane bagasse. MALDI-TOF-MS and HPLC analysis of XOS showed the formation of xylobiose, xylotriose and xylotetraose with xylobiose as the major product. The conversion of bagasse to XOS was >99% with negligible amount of xylose (0.4%). NMR analysis of XOS mixture indicated the presence of arabinosyl and glucuronyl substituted XOS. The relative content of substituted XOS in the mixture was 32%. The XOS mixture supported growth of probiotic bifidobacterial strains under anaerobic conditions. The bifidobacterial strains completely utilized XOS with production of short chain fatty acids indicating their prebiotic function. The concentration of fatty acids formed was in the order of acetate, formate and lactate. Hence, the present method would be useful for further development of low-cost process for production of high-pure prebiotic XOS from lignocellulosic materials.

Conversion of sugarcane bagasse to gaseous and liquid fuels in near-critical water media using K2O promoted Cu/γ-Al2O3–MgO nanocatalysts

Bagasse conversion to H2, CO and light gaseous hydrocarbons as gaseous fuels, and higher alcohols and ethers as liquid fuels and fuel additives were performed in a basic water medium with near-critical condition in presence of potassium promoted Cu/γ-Al2O3–MgO catalysts. The catalysts were extensively characterized using ICP, XRD, TPR, BET, CO chemisorption and TEM techniques. In order to investigate support stability at reaction condition, XRD test also was carried out for used catalysts. Maximum dispersion of 48% and minimum average particles sizes of 8.4 nm were obtained for Cu20–K7.5/γ-Al2O3–MgO catalyst. Copper and potassium effects on quality and quantity of gaseous and liquid products were investigated. The maximum amounts of H2 (10 mmol g−1 of bagasse) and total produced gases (41 mmol g−1 of bagasse) were obtained with unpromoted Cu20/γ-Al2O3–MgO catalyst. Addition of K increased the bagasse conversion to liquid fuels. Potassium made the process more selective for alcohols and ethers production. Maximum amount of alcohols and ethers (83.3 mmol g−1 of bagasse) was obtained for Cu20–K7.5/γ-Al2O3–MgO catalyst.

Alkaline pretreatment and the synergic effect of water and tetralin enhances the liquefaction efficiency of bagasse

Bagasse liquefaction (BL) in water, tetralin, and water/tetralin mixed solvents (WTMS) was investigated, and effects of tetralin content in WTMS, temperature, and alkaline pretreatment of bagasse on liquefaction efficiency were studied. At 300°C, bagasse conversion in WTMS with tetralin content higher than 50wt% was 86–87wt%, whereas bagasse conversion in water or tetralin was 67wt% or 84wt%, respectively. Because the solid conversion from liquefaction in WTMS with tetralin content higher than 50wt% was always higher than that in water or tetralin at temperatures between 250 and 300°C, a synergic effect between water and tetralin is suggested. Alkaline pretreatment of bagasse resulted in significantly higher conversion and heavy oil yield from BL in water or WTMS. The effect of deoxygenation by the present liquefaction method is demonstrated by lower oxygen contents (16.01–19.59wt%) and higher heating values (31.9–34.8MJ/kg) in the produced oils.