Delignification Process Research Articles

THE USE SKIN STARCH OF JACKFRUIT (Artocarpus heterophyllus) AND CHITOSAN IN A BIOPLASTIC PRODUCTION WITH THE ADDITION OF VIRGIN COCONUT OIL (VCO) AS PLASTICIZER

This study aims to determine the best concentration on the comparison of jackfruit skin starch and chitosan with the addition of virgin coconut oil (VCO) as a plasticizer and the characteristics of bioplastics. The research method consisted of the following steps: extracting jackfruit skin starch using two processes, namely the delignification process and the bleaching process. The production of bioplastics was carried out with the following treatments: Jackfruit skin starch: chitosan, each with a ratio of P1= 100%:0%; P2 = 85%:15%; P3 = 70%:30% and P4 = 55%:45% with the addition of VCO of 10% of the total starch of jackfruit skin and chitosan and stirred for 1 hour until homogeneous. The resulting solution was then printed on a glass mold with a size of 20 x 15 cm and dried in an oven at 60 o C for 6 hours. The bioplastics were cooled at room temperature for 6 hours then removed from the glass plate and stabilized in a desiccator before being analyzed. Data analysis used the Completely Randomized Design (CRD) method with 4 treatment levels and three replications. The results showed that the addition of chitosan and VCO had a very significant effect (p<0.05) on the characteristics of bioplastics. The best treatment ratio was obtained in the ratio of jackfruit skin starch: chitosan 55%:45% with each thickness value of 0.1682 mm, tensile strength of 0.5933 MPA, 20% water absorption and 50% biodegradability test which can be degraded for 3 weeks.

Hierarchically porous carbon derived from delignified biomass for high sulfur-loading room-temperature sodium-sulfur batteries

The commercial applications of room-temperature sodium-sulfur battery still suffers from low sulfur utilization and poor reaction kinetics. Here, we develop a novel carbon material with hierarchical pores from camellia oleifera seed cake as the host of sulfur by introducing a delignification process followed by KOH activation. The large specific surface area (1362 m2 g−1) and well-developed porosity produced by the two-step method make it possible to realize high sulfur content (61.9 wt%). By the physical confinement of micropores, the formation of Na2Sx (4 ≤ x ≤ 8) is effectively suppressed to avoid the side reactions. The mesopores and macropores optimize the electrolyte accessibility. The sulfur-loaded carbon cathode delivers a reversible capacity of 702 mAh g−1 after 100 cycles at 0.1 C (1 C = 1675 mAh g−1). Even at 1 C, a reversible capacity of 404 mAh g−1 has been achieved after 300 cycles. This work demonstrates a sustainable cathode with a high sulfur content for the practical application of room-temperature Na–S batteries.

Delignification of Cassava Peel by Using Alkaline Hydrogen Peroxide Method: Study of Peroxide Concentration, Solid/Liquid Ratio, and pH

Cassava peel is a natural material with cellulose content reaching 33.33%. In order to utilize cassava peel as a biodegradable polymer and renewable energy alternative, a delignification process is essential to separate cellulose from hemicellulose and lignin, which prevents the penetration of cellulose hydrolyzer. The delignification method chosen in this study was alkaline hydrogen peroxide (AHP). The AHP is based on the autoxidation of lignin using hydrogen peroxide (H2O2) in an alkaline environment. This method was chosen because it can damage the lignocellulosic structure with relatively low energy and is more selective for lignin. However, under certain conditions, AHP can trigger carbohydrate depolymerization, which decreases yield. Therefore, it is necessary to study the effect of H2O2 concentration, Solid/Liquid ratio (S/L) (w/v), and pH to evaluate the effectiveness of lignin removal in cassava peel. The concentration of H2O2 was varied into 1.5%, 3%, 4.5%, 6%, and 7.5%. The S/L ratio is varied to 1:3, 1:5, 1:7, 1:9,1:12. The pH of the solution was varied to 8, 9, 10, 11, and 12. The reaction temperature was maintained at 70-90 °C for 3 hours. The results showed that lignin could be reduced to 84.05% for 3 hours by using 6% H2O2, an S/L ratio of 1:5, and a pH of 11. The reaction carried out under these conditions can also increase the amount of cellulose from 33.33% to 49.00%.

Cellulose Extraction from Coconut Coir with Alkaline Delignification Process

Coconut has been known for its benefits in human life. Coconut coir, as part of coconut which is considered as waste, contains useful components. It contains high cellulose which is could be used in fiber industries. Meanwhile, coconut coir also contains lignin which needs to be separated. In this study, a delignification process was used to remove the brown color on the fiber caused by the lignin content. The delignification process was a pretreatment before the cellulose extraction was carried out. It had been done in the various NaOH concentration (0.5; 1; and 1.5 M), reaction time (1; 1.5; and 2 hours) and the reaction temperature (60,70, and 80 oC). This study aims to determine the cellulose content and the factor that affected the cellulose extraction and the characteristics of the cellulose extracted from the coconut coir. The Chesson Data method and SEM analysis have been used for the characterization of the cellulose. The delignification method known has the potential as a simple and effective method for extracting cellulose from natural materials. The result shows that the optimum cellulose content obtained at 100 mesh coir particle size, 1.5 M NaOH concentration, at 80°C for 1.5 hours was 69.82 %.

Finite Element Analysis of Strengthening Mechanism of Ultrastrong and Tough Cellulosic Materials.

Superior strong and tough structural materials are highly desirable in engineering applications. However, it remains a big challenge to combine these two mutually exclusive mechanical properties into one body. In the work, an ultrastrong and tough cellulosic material was fabricated by a two-step process of delignification and water molecule-induced hydrogen bonding under compression. The strong and tough cellulosic material showed enhanced tensile strength (352 MPa vs. 56 MPa for natural wood) and toughness (4.1 MJ m-3 vs. 0.42 MJ m-3 for natural wood). The mechanical behaviors of ultrastrong and tough bulk material in a tensile state were simulated by finite element analysis (FEA) using mechanical parameters measured in the experiment. FEA results showed that the tensile strength and toughness gradually simultaneously improved with the increase in moisture content, demonstrating that water molecules played an active role in fabricating strong and tough materials, by plasticizing and forming hydrogen bonding among cellulose nanofibrils.

Characterization of a Translucent Material Produced from Paulownia tomentosa Using Peracetic Acid Delignification and Resin Infiltration

Paulownia tomentosa, a tree species that allows for efficient production of translucent wood, was selected as an experimental wood species in this study, and a two-step process of delignification and polymer impregnation was performed. For delignification, 2–4 mm thick specimens were immersed in peracetic acid for 8 h. The delignified-wood specimens were impregnated using epoxy, a commercial transparent polymer. To identify the characteristics of the resulting translucent wood, the transmittance and haze of each type of wood section (cross- and tangential) were measured, while bending strength was measured using a universal testing machine. The translucent wood varied in properties according to the wood section, and the total transmittance and haze were 88.0% and 78.5% for the tangential section and 91.3% and 96.2% for the cross-section, respectively. For the bending strength, untreated wood showed values of approximately 4613.5 MPa modulus of elasticity (MOE), while the epoxy impregnation to improve the strength of the wood had increased the MOE up to approximately 6089.9 MPa, respectively. A comparative analysis was performed in this study with respect to the substitution of balsa, which is used widely in the production of translucent wood. The results are anticipated to serve as baseline data for the functionalization of translucent wood.

Microbial Pre-treatment of Lignocellulosic Biomass for Biofuel Production: A Review

Lignocellulosic biomasses (LCB), second-generation biofuels are used as an alternative means to cope with the burning issues of depleting fossil fuels like petroleum products with the added advantage of renewability, lower emission, and lesser pollution. For the increment in the production of LCB biofuels, microbial pre-treatment processes are conducted which accelerates the degradation of organic polymers like lignin and hemicellulose with the activity of potential microorganisms. To increase the efficiency of degradation of hemicellulose, hemicellulolytic fungi including Trichoderma and Aspergillus and other bacteria produce multi-enzymatic complexes like cellulosomes. Similarly, organisms like Tinea versicolor, Dichomitus squalens, Phlebia floridensis, Daedalea flavida, and Phlebia radiata contain lignin-degrading auxiliary enzymes and lignin modifying enzymes like laccase and heme-containing peroxidase which aid in delignification process. Several factors are associated with pre-treatment processes like the type of strain, inoculum load, pH, temperature, fatty acids, C/N ratio, time, aeration, grindability, surface area, particle size, and supplements added. To enhance the pretreatment method, the combination of microbial with physical, chemical, and mechanical methods is suggested which leads to a synergistic effect and better yield of the final product. Overall, biofuels should be more employed and this review aims to bring light to the microbial pre-treatment approaches which can aid in the efficient production of biofuels that can directly contribute to environmental sustainability.

Biobutanol Production from Rice Husk

Abstract: This research aimed to study biobutanol production using Lignocellulosic renewable substrate Rice Husk, carried out using Clostridium acetobutylicum MTCC 11274 via the Separate hydrolysis and fermentation (SHF) process. The simple sugars were exposed using a delignification process with different concentrations of Ammonia solution and some were hydrolyzed using conc. H2SO4 after getting treated with ammonia. The sugars were estimated using DNSA Method after which samples were fermented. The concentration of Biobutanol was estimated using GC-MS showing 2.2 gm/L in one of the tested samples.

Light transmittance of mahogany wood treated with 20% hydrogen peroxide solution

There is an increased research interest in methods for transparent wood production and its use. Wood transparency could be achieved by its delignification followed by an impregnation process with polymers having proper optical properties. However, delignification processes are mainly time consuming and not environmentally friendly. The possibility of treating mahogany wood (Swietenia macrophylla King) with 20% hydrogen peroxide for 70, 100, 135, and 170 min at 103 °C is presented in this research. According to the treatment duration, lignin content decreased 40 to 94% relative to its initial content in the control samples, whilst the cell structure remained intact. Due to the light scatter effect, caused mainly by wood tissue structure, the direct optical transmittance of treated samples in the visible light spectrum (400 to 800 nm) was less than 40%. Simultaneously, the total optical transmittance of samples treated for 100 and 135 min reached values between 70 to 80% with high values of the haze at approximately 30 and 60%. Optical transmittance in the visible spectrum area of the samples treated for 170 min was from 45 to 80% and the haze from 25 to 45%.

The effect of adding NaOH and fermentation time on Robusta coffee husk (Coffea canephora) bioethanol production with SSF (Simultaneous Sachraffication and Fermentation) method

Robusta coffee husk is one of the largest agricultural wastes and contains lignocellulose as a raw material for bioethanol production. Lignin in Robusta coffee husk can interfere with the enzymatic hydrolysis process, so a delignification process using NaOH solution is needed to remove it. This research aimed to determine the effect of adding NaOH and fermentation time on the bioethanol production from Robusta coffee husks using the SSF (Simultaneous Saccharification and Fermentation) method. Removal of lignin using NaOH with various concentrations of 6, 8, and 10% and fermentation time for 24, 48, 72, 96, and 120 hours. The cellulose, hemicellulose, and lignin contents in the delignification results were tested using the Chesson method. The saccharification and fermentation steps used cellulase enzymes and Saccharomyces cerevisiae. Bioethanol levels were analyzed using GCMS. The results showed that the optimal concentration of NaOH to remove lignin was 10% which generated 17.40% lignin content, 20.81% cellulose, and 3.79% hemicellulose. The highest bioethanol content was 100% obtained with a fermentation time of 72 hours. The data showed that adding of NaOH and fermentation time affected bioethanol production.

Sugarcane Stem Derived Hybrid Scaffold for Bone Tissue Engineering via Top-down Approach

ABSTRACT A novel bone tissue engineering material with a merit of good biocompatibility and excellent mechanical properties was fabricated with a top-down method. In this work, sugarcane was first treated in NaClO2/acetate buffer to remove lignin, i.e. delignification, and the effect of delignification on pore size of sugarcane is explored bby varying the soaking time in the buffer. Results show that 4 h is the optimal delignification time to ensure good mechanical properties of the sugarcane. The subsequent surface modification with alendronate trihydrate has an advantage to facilitate the final deposition of hydroxyapatite (HAp) due to the fact that the introduction of phosphate groups can effectively improve the nucleation efficiency of HAp. We found that the deposited HAp on sugarcane stem templates can form a bioactive hybrid scaffold material with a hierachical pore structure. Fortunately, during the delignification process of the cellulose structure in the sugarcane stem is not destroyed, thus the hierarchical pore structure remains. The final obtained hybrid scaffold presents a three-dimensional anisotropic porous structure and its longitudinal strength is much higher than the radial strength. The anisotropic property can provide a good mechanical support for scaffold applications. Moreover, the CCK-8 test shows that the cell viability is higher than 95%, indicating that the scaffold exhibits no cytotoxicity. Our investigation demonstrates that the presented hybrid scaffold derived from sugarcane stem has a great potential in the application of bone tissue engineering.

A new Enzolv process for simultaneous delignification and lignin-derived chemical production from the woody biomass of Melia dubia

A new Enzolv process for simultaneous delignification and lignin-derived chemical production from the woody biomass of Melia dubia

Application of cellulose of Boehmeria nivea as natural flocculants in direct flocculation

The use of cellulose which is a natural polymer as a flocculant has been widely used, however, the extraction of cellulose from plants has not been widely studied, particularly extracted from Boehmeria nivea (ramie). In this research, the stem of ramie came from the waste of textile raw material. The isolation of α-cellulose is done through pre-hydrolysis, delignification, and bleaching processes. In this research, there are 6 types of α-cellulose that are isolated from the stem of ramie, depending on the sodium hydroxide concentration in the delignification process. The isolated α-cellulose is characterized using Fourier-transform infrared spectroscopy (FTIR) and tested its flocculation ability through jar-test apparatus with 5 gr/L kaolin suspension as synthetic water samples and turbidity as the test parameter. The coagulation-flocculation experiments were carried out without the addition of a coagulant, which is called the direct flocculation method. Data analysis was performed by One-Way ANOVA statistical analysis, with Duncan’s multiple range test as the post-hoc analysis. It is concluded that cellulose is a good candidate biomaterial for natural flocculants in removing turbidity and further modification of α-cellulose with cationic grafts will be carried out for the next stage of research.

Influence of peracetic delignification on biomass lignocellulosic complex

The process of delignification of plant biomass with peracetic acid was studied and the effect of the duration of peracetic delignification on the degree of delignification and the degree of removal of the carbohydrate complex in the final cellulose products was established. The treatment of different representatives of plant biomass was performed with peracetic acid at a concentration of 8% and at different time of the process. The study was focused on the process of chemical treatment of six different representatives of non-wood plant raw materials in the form of straw, agricultural waste, as well as stems of fast-growing industrial and fodder crops. Cellulose products were obtained with a yield of about 50% and a whiteness of greater than 60%. It was shown that an increase in the duration of processing naturally leads to a decrease in the yield of the final product, which is associated with the intensive oxidation and removal of lignin, as well as partial destruction of the polysaccharide component of biomass. The investigated method of delignification proved to be effective for the removal of more than 90% of lignin in the entire studied time interval, but the selectivity of the removal of lignin and carbohydrates depended significantly on the type of plant material. By an increase in the efficiency of lignin removal with peracetic acid, the studied plants are located in the following row: sverbiga (bunias orientalis)>shchavnat>lavatera>rapeseed>wheat straw>amaranth. Conducted research work gives grounds to claim that peracetic delignification is an effective method of chemical treatment of plant biomass; it allows obtaining cellulose products that can be used in the production of paper products for various purposes, as well as for the chemical industry.

Impact of Carboxymethylation Pretreatment on the Rheology of Cellulose Nanofiber from Bleached Rice Hull

Rice is widely produced; however, large quantities of non-edible biomass are also generated during its production, mainly straw and hulls. These lignocellulosic materials have great value potential but are less used than other biomass resources. We produced cellulose nanofiber (CNF) from rice husks through delignification (as chlorine dioxide bleaching), pretreatment (as carboxymethylation substitution reaction), and nanofiber-making processes (as supermass-collider grinding and high-pressure homogenization). The rheological properties of rice-hull cellulose nanofiber were investigated to determine the relationship between carboxyl content, number of grinding, and high-pressure homogenization to rheological properties of rice-husk CNF gels. Increased carboxymethylation and mechanical treatments lead to higher viscosity, better hydrogel strength, and water retention value (WRV). Further mechanical processes decreased the viscosity and hydrogel strength after attaining the maximum value. For high-quality hydrogel production, optimum pretreatment and mechanical processes are required as pretreatment to DS 0.3 for carboxymethylation and optimum grinding and high-pressure homogenization combination.

Laboratory Study On The Utilization of Jackruit Skin Waste Into Car-boxymethyl Cellulose and Their Effect On The Rheological Properties Of Drilling Mud

The value rheology of drilling mud must be in accordance with the conditions of wellbore that do not lead to the occurrence of the problems at the time of drilling. One of the efforts to improve the rheology of drilling mud is by adding Carboxymethyl Cellulose (CMC) which is useful for increasing viscosity and binding water. This study aims to identify the effect on the use of CMC originating from jackfruit skin to the rheological properties of drilling mud. Jackfruit skin is an underutilized organic waste and the structure of jackfruit skin contains 50-55% cellulose. Manufacturing phase of synthesizing CMC skin jackfruit includes the process of delignification, alkalization, carboximetilation, and sieve sample to be powdered CMC and subsequently carried out the test of plastic viscosity, yield point , gel strength by using a Fann VG Meter and mud cake using a marsh funnel and volume filtration using a filter press . The added mass of CMC jackfruit skin were varied from 1 g, 2 g, 3 g, 4 g to 5 g. The results suggest that the addition of jackfruit skin CMC has an effect on the rheology of drilling mud. Increasingly many additions additive CMC skin jackfruit who use the increasingly high- value rheology mud drilling were obtained. Furthermore, the addition of CMC jackfruit skin starting from 1gr – 5 gr meets the API 13, a standard for the value of yield point/viscosity plastic, plastic viscosity and maximum volume of filtrate. While the value of gel strength which meets the API 13 A is with the addition of CMC jackfruit skin as much as 5 grams.

Efficient delignification of sugarcane bagasse by Fenton oxidation coupled with ultrasound-assisted NaOH for biotransformation from Agaricus sinodeliciosus var. Chaidam

Sugarcane bagasse (SCB), a widely available lignocellulosic by-product, could be potentially used in macrofungal bioconversion for high-value bioactive compounds. For macrofungus with poor lignin degradation capacity, its recalcitrant lignin structure blocked the release of fermentable sugars for cell growth. Herein, the main objective was to construct an effective delignification pretreatment strategy for SCB biotransformation and synthesis of bioactive substances by Agaricus sinodeliciosus var. Chaidam. Different pretreatments including chemical (alkali and Fenton oxidation) and ultrasound methods were used to intensify the delignification process. Physico-chemical characteristics of native and pretreated SCB were examined via XRD, XPS, FT-IR and 13C ssNMR to characterize crystallinity index, surface lignin and chemical structure. Lignocellulose-degrading enzymes were also used to assess the ability of the macrofungus to degrade SCB. By comparing morphological structure, chemical composition and fermentation characteristics, a suitable multiple sequential pretreatment method was finally identified. Our findings revealed that Fenton-ultrasound-alkali pre-treatment has an optimum delignification effect on SCB with never-uncovered excellent ability to detoxify harmful substances produced by Fenton oxidation. Under this pretreatment condition, the cellulose content was increased by 106.45%, whereas hemicelluloses and lignin were decreased by 48.34% and 74.15%, respectively. The macrofungal growth, intracellular polysaccharides, total phenols and terpenoids formation were 2.4, 1.46, 1.36 and 1.66 times higher than those of the untreated, respectively. Fermentation kinetic results showed outstanding fit and prediction of macrofungal growth and enzymatic activity secretion on above pretreated SCB. This study shed light on developing a novel pretreatment strategy for low-cost SCB lignocellulose transformation into high-value products.

“Top-down” fabrication of anisotropic, lightweight, super-amphiphobic, and thermal insulating rattan aerogels

Lightweight and sustainable aerogels have been a growing interest for thermal insulation applications due to current environmental and energy challenges. The design of cellulose-based aerogels with thermal insulation, hydrophobic, and oleophobic performance is the future development direction for building energy-efficient buildings. Herein, an anisotropic, lightweight, super-amphiphobic and thermal insulating rattan aerogel was fabricated by a three-step process of delignification, freeze-drying, and silylation. The prepared rattan aerogel exhibits anisotropic thermal properties with a low thermal conductivity of 0.030 W m–1 K–1 in the radial direction and 0.056 W m–1 K–1 in the axial direction due to the run-through channel skeleton and the structure of the insulating cages. Moreover, the silylated rattan aerogel shows super-amphiphobic performance (water contact angle ∼164° in the cross section and ∼156° in the radial section; oil contact angle ∼158° in the cross section and ∼154° in the radial section). The excellent anisotropic thermal performance, abundance, sustainability, and superb amphiphobicity of the rattan aerogel make it highly promising for green buildings and thermal management applications.

Modification of Orange Bagasse with Reactive Extrusion to Obtain Cellulose-Based Materials

Orange bagasse (OB) could be considered a sustainable, renewable, and low-cost biomass for the extraction of cellulose. In this context, reactive extrusion can be considered an excellent, eco-friendly, alternative process for the extraction of cellulose from lignocellulosic materials. Thus, the present study aimed to obtain cellulose-based materials with a reactive extrusion process and also to investigate the impact of pectin on the delignification process. Two groups of samples (OB and depectinizated OB) were submitted to extrusion with sulfuric acid or sodium hydroxide in one-step processes. The cellulose content of extruded materials was highly affected by pectin content in the raw material; the thermal profile (TGA curves) and crystallinity also changed. The cellulose content of modified materials ranged from 18.8% to 58.4%, with a process yield of 30.6% to 79.2%. The alkaline reagent provided the highest cellulose content among all extrusion treatments tested, mainly for OB without pectin. The extrusion process was considered an efficient and promising process for extracting cellulose from citrus residue. Materials produced in this study can be used as sources of cellulose fiber for various products and processes, such as in the food industry, fermentation substrates, or refined applications after subsequent treatments.

Multifunctional cellulose wood with effective acoustic absorption

Wood is a sustainable material with big sound absorption potential based on its natural porous characteristics. However, the acoustic absorption performance of wood is greatly limited by the low permeability of wood structures. In this study, we prepared a new type of cellulose wood (CW) using a two-step delignification process on a natural basswood matrix followed by supercritical CO2 drying. The as-prepared CW exhibited a high air permeability of 33.78 Darcys (increase of 496.82%) and superior porous characteristics compared to the natural basswood, resulting in a significant improvement in the acoustic absorption performance with an increased average absorption of 106.25% and maximum absorption of 126.32%. The dissipation of sound energy in the structure of CW is well predicted by a designed porous media model. Moreover, a high specific stiffness of 2.14 × 105 m2 s−2 and a diffuse reflectance of 97.02% across the visible light were demonstrated for the CW as well. Such a fascinating multifunctional wood-derived material may provide new insights into the development of efficient and sustainable acoustic absorbers for various applications.