Sugarcane Bagasse Waste Research Articles

Application of Sugarcane Bagasse in Chemicals and Food Packaging Industry: Potential and Challenges

Recent research and development in the field of sugarcane bagasse processing offers a promising hope to the sugarcane industries. Various value-added bioproducts and technologies have been developed by the utilization of waste sugarcane bagasse. Other applications such as the production of energy, biodegradable material, packaging products, construction, and bioadsorbents still need to be evolved more so that the remaining sugarcane bagasse can be utilized. Few limitations of sugarcane bagasse valorisation make difficulties in the commercialization of green technologies; therefore, there is a need to develop efficient processes to utilize it as a raw material for value-added products and various other applications.

Application of activated charcoal- sugarcane bagasse material for adsorption of COD (Chemical Oxygen Demand) on the sasirangan wastewater

In Indonesia, there is a significant amount of sugarcane bagasse waste that has not been utilized optimally. Around 50% of sugarcane bagasse waste is discarded as waste with little economic value. Sugarcane bagasse contains lignocellulose, composed of 20% hemicellulose, 52.75% cellulose, 20% pentosan, and 37.55% lignin and converted into activated charcoal. Sugarcane bagasse can be used as an alternative raw material for activated charcoal by carbonizing it in a batch process to remove organic compounds from the waste. On this basis, a study was conducted to determine the effectiveness of bagasse activated charcoal in reducing the COD content of sasirangan waste and the optimal dose of bagasse activated charcoal as an adsorbent in reducing the COD content of sasirangan wastewater.The steps to make activated carbon are by place small pieces of bagasse in the mortar and place in a 350°C furnace for 2 hours or until the sample turns black. Next, bagasse charcoal was sieved until smooth using a 100-mesh sieve. The following stage is chemical activation. Bagasse that has passed through the sieve is soaked in 0.1 N 20% HCl activator for the day—cleansing the activated charcoal with distilled water until the pH is neutral. The next step is physical activation, which involves heating the activated charcoal in an oven at 105°C for six hours to dehydrate it. The results indicated that bagasse activated charcoal with a pH of 5 and a contact time of 90 minutes could reduce the COD content of the Sasirangan wastewater by up to 95.37 % and that the dose of bagasse activated charcoal as an adsorbent had a significant effect on the COD content. The quantity of 5 g/L is the maximum number of COD that can be absorbed. Keyword: Activated Charcoal, COD, sasirangan wastewater

Eco-friendly approach toward preparation of plantable paper like material from organic sugarcane Bagasse waste

Present research work focused on sugarcane bagasse powder having potential cellulose source which can be used in pulp and paper industries. Ecological concerns have increased the need for nonwood pulp as a low cost raw material for paper making. This also led to the development of alternative pulping technologies that are eco-friendly. Cellulose pulp from the generated agro based waste is collected from the street vendors and chemically prepared in the laboratory and used in paper making. The optimal cooking time and dose of pulp by moist weight found were 180 minutes & 150 g of pulp per frame, respectively. To improve the quality and the shelf life of paper we incorporated sucrose in the sugarcane pulp. Sucrose acts as a natural preservative. To study the effect of sucrose as preservative we prepared a solution of sucrose and distilled water in 1:4 ratio. The solution is then mixed with sugarcane bagasse in 5:250, 10:250, 15:250 and 20:250 and observed the OD of the mixture on 20th and 27th day. By using this pulp we developed a paper with incorporated artificial seeds within it, so that after use of this paper rather than discarding the paper simply sowing it in garden soil a plant will grow from it and generate a means of eco initiatives. This plant able paper is developed by handmade process without using any harmful chemicals and can be made using everyday use material. Anyone can use this method and make the paper. The paper obtained from this process is found to be of good quality and durable and can be used for preparation of commercial Kraft’s of different purposes like greetings card, packaging etc., and can generate new way of a revenue.

Reduced graphene oxide incorporated polyvinylidene fluoride/cellulose acetate proton exchange membrane for energy extraction using microbial fuel cells

A superior cost-effective cation exchange membrane based on polyvinylidene fluoride (PVDF), cellulose acetate (CA), and reduced graphene oxide (rGO) work as a superior cost-effective cation exchange membrane for the energy extraction application employing microbial fuel cells (MFCs). In this work, waste sugarcane bagasse was used to make CA, and the Tour technique was employed to make GO, which was then transformed to rGO using multiple modifications. To prepare cation exchange membranes, the CA and rGO were doped. The obtained proton conductivity values increased from 0.01 Scm−1 for rG0 to ∼ 0.4 Scm−1 for rG1 when the manufactured membranes were sulfonated. The combination of CA derived from sugarcane bagasse and rGO in the produced membranes may be attributed to this enhancement in proton conductivity. The power density performance of rG1 was compared to that of commercially available high-performance proton exchange membranes. It was revealed that MFC employing the rG1 membrane outperformed several more expensive membranes when it came to energy extraction using MFC. Without any electrode alteration, a columbic efficiency (CE) of 6.17 %, a COD removal efficiency of 92.0 ± 0.8% %, and a power density of more than 118 mW m−2 were reached. As a result, the constructed low-cost new PVDF-based, rGO, and CA membrane (rG1) shown its suitability for increasing MFC efficacy and is recommended for MFC scaling up.

Natural Fiber Incorporated Polymer Matrix Composites for Electronic Circuit Board Applications

There are many more applications for fibre-reinforced epoxy composites than there are for metals and alloys today. For example, sustainable, recyclable, and biodegradable reinforcements have been used in numerous studies to improve the mechanical and thermal properties of composite materials. It was discovered that the properties of epoxy-based composites could be improved by combining biosolid waste sugarcane bagasse ash fillers, madar fibre, and epoxy resin. Conventional compression molding techniques were used to prepare the sugarcane bagasse ash (SBA) particles and madar fibre-reinforced epoxy resin-based composites (PMCs), which were loaded with varying amounts of fibre and fillers. Hybrid biocomposites were evaluated for mechanical (tensile, flexural, impact, and hardness) and water absorption characteristics. Epoxy matrix composites containing 28 wt.% madar fibre and 7 wt.% sugarcane bagasse ash fillers had tensile, flexural, hardness, and impact values of 61 MPa, 147 MPa, and 54 kJ/m2, respectively.

Physio-chemical evaluation and Co-combustion efficiency of different biomass waste fractions with indigenous coal blends for utilization as alternative fuel

<p>Severe energy crisis and vilest economic conditions in Pakistan demand the country’s energy portfolio to be revised with increased reliance on indigenous energy resources. The perspective of utilization of abundantly available biomass waste fractions as a fuel alone and their co-combustion with two different indigenous coal varieties has been emphasized in this study. Coal samples were blended with the organic fraction of municipal solid waste, rice husk and sugarcane bagasse waste fractions in varying ratios of 20%, 40%, 60% and 80% and the resulting variation in their fuel characteristics and co-combustion efficiency was determined. The execution is a basis to assess the assumption that co-combusion in appropriate proportions can arrange a solution for the massive amounts of produced organic waste and cut dependency on imported energy sources. The tanner diagram visualization for the assessment of proposed blends suggest that the blending samples exhibit an increase in moisture and combustible content while some decrease in ash content and calorific values with increased biomass ratios. Within the assortment of conducted trials, khaushab coal and rice husk in various proportions evidenced to be the best arrangement for fuel consumption based on energetic optimization. The overall results of studies inferred that both coal and biomass fuels alone and their co-firing can sustain self-combustion and subsequently arrange for finding area based solutions related to various energy operations.</p>

Non linear regression analysis and response surface modeling for Cr (VI) removal from aqueous solution using poly-aniline coated sugarcane bagasse (PANI@SB) composites as an adsorbent

Hexavalent chromium has been found most hazardous pollutants being discharge from many industrial sectors like chromite mines, electroplating industries, leather and tanning industries etc. and need to be controlled before discharge to save natural water resources. Adsorption is one of the best and economic process for hexavalent chromium removal. In present investigation, agricultural waste sugarcane bagasse has been coated with polyaniline and PANI@SB composites were synthesized as an adsorbent for the removal of Cr (VI) from its aqueous solution by adsorption process. Batch adsorption was conducted to optimize the dose of adsorbent, pH, time and concentration. The optimum condition has been found are pH 2.0, 0.3 g adsorbent dose, 10 mgL−1 initial concentration at 303 K. Multilayer adsorption of Cr (VI) was found to occur on the heterogeneous surface of PANI@SB with maximum adsorption capacity of 35.2 mgg−1 at 303 K. It was observed that adsorption data fitted well to the Freundlich isotherm model and pseudo- second-order model with high R2, low chi square (χ2), low root mean square error (RMSE) and low standard deviation (SD) values by applying non linear regression method. Positive values of enthalpy and Gibbs free energy of adsorption suggest endothermic and spontaneous nature of adsorption occurs. FESEM, EDX, XRF, HR-TEM, FTIR, XRD, AFM, BET surface area and XPS analysis were conducted to understand the surface characteristics of PANI@SB before and after adsorption of Cr (VI). Response surface modeling (RSM), a statistical tool, was applied to experimental data to optimize the process parameters. A quadratic model equation was generated between the process parameters and response for Cr (VI) removal. The optimization study from RSM showed that pH and adsorbent dose has significant effect on removal of Cr (VI) due to higher lack of fit (F) value. The optimum conditions for maximum removal of 97% Cr (VI) are found at pH 2.0 with 0.3 g of adsorbent dose, time of 90 min at 303 K obtained by RSM. PANI@SB is regenerated with 0.2 N NaOH and can be reused up to two desorption-adsorption cycles (removal 92%) with slight decreases in its original sorption capacity. On the basis of this study it is found that PANI@SB is very efficient, stable, reusable and effective adsorbent for removal of Cr (VI) from aqueous medium and it can be used in industrial scale.

Sugarcane bagasse waste fibers as novel thermal insulation and sound-absorbing materials for application in sustainable buildings

Global warming and noise pollution have emerged as the most serious environmental problems ever to confront humanity. In recent years, the use of natural fibers as thermal insulation and sound absorption construction materials has received much attention. Sugarcane bagasse waste (SBW) is an agro-industrial by-product, abundantly produced in sugar processing plants. Endowed with intrinsic surface roughness, SBW fibers are expected to exhibit high thermal and acoustic performance. To this end, SBW as an eco-friendly material was used to fabricate fibrous samples of different densities and thicknesses. The thermal insulation and sound absorption performance of the specimens were investigated using the guarded hot plate and impedance tube techniques, respectively. Additionally, the surface morphology and tensile properties of the SBW fibers were investigated using the FE-SEM and universal tensile tester. The thermal conductivity values of the specimens were found to range between 0.034 and 0.042 W/mK. The sound absorption average (SAA) and noise reduction coefficient (NRC) of the prepared samples were between 0.26-0.64 and 0.27–0.62, respectively. The results pointed to the good performance of the SBW fibers in the low- and mid-frequency ranges. The acoustic characteristics of the specimens were also studied by the Johnson-Champoux-Allard and statistical models and good agreement with experimental data was noticed. It was concluded that SBW as an innovative sustainable construction material provides competitive performance in terms of thermal and acoustical characteristics compared with its natural and nonrenewable counterparts.

Distinguished performance of biogenically synthesized reduced-graphene-oxide-based mesoporous Au–Cu2O/RGO ternary nanocomposites for sonocatalytic reduction of nitrophenols in water

Au-Cu2O supported on reduced graphene oxide was synthesised employing a novel one pot greener approach using sugarcane bagasse waste and Fehling’s solution. It was used for catalytic reduction of nitrophenols under ultrasonic irradiation in water.

Hydrothermal Carbonization of Waste Sugarcane Bagasse for the Effective Removal of Emerging Contaminants from Aqueous Solution

Porous carbon spheres were fabricated from sugarcane bagasse using a sustainable hydrothermal carbonization process followed by alkali impregnation inert atmosphere activation. Developed spheres were technically analysed for their chemical science, structural morphology, texture, porosity with respect to size distribution, and thermal degradation. Spheres are functionally enriched with oxygenated groups showing amorphous nature portraying as a smooth surface. After activation, intensity of functional groups is reduced due to reduction reaction by KOH thereby yielding highly rich porous carbon. The active surface area developed on spheres is 111 m2 g-1 holding pores that are mesoporous in nature. Resistance to thermal exposure using TGA showed that decomposition of hemicelluloses followed by cellulose yielded aromatized carbon-rich skeleton through thermal degradation of carboxyl and hydroxyl groups. Developed carbon was found to be effective in removing Ciprofloxacin Hydrochloride from water with maximum adsorption capacity of 110.008 mg g-1. Mechanistic removal followed pseudo-second-order kinetics along with Freundlich mode of adsorption. The presence of carboxylic and hydroxyl groups in porous carbon favoured elimination of CPF from water. The development of HTC-derived carbon helped conserving the energy thereby reducing the cost requirement.

Mechanical properties and corrosion behavior of sugarcane Bagasse fiber reinforced Low Density Polyethylene composites

In the recent decade, there has been an increase in global warming, environmental changes, and other issues. Environmentally friendly products, such as natural composite materials, are being developed by researchers and academics to protect life on the planet. The purpose of this research is to see if cellulose and cellulignin fibres obtained from sugarcane bagasse (SCB) waste may be used as reinforcing filler in a thermoplastic polymer matrix. The injection method was used to create the low density polyethylene (LDPE) and sugarcane bagasse (SCB) composites. Fiber loading was set to be varied from 10 to 30 wt%. To improve interfacial bonding, the fibres were chemically modified using an alkali treatment, and the effects on the fiber/matrix interaction were evaluated using scanning electron micrographs (SEM). Tensile, impact, and hardness were used to determine the mechanical properties and corrosion tests. The findings revealed that sugarcane bagasse fibers, like other natural fibers, strengthen polyethylene. It has been found that the tensile strength and tensile modulus of the treated SCB fibers have been improved significantly by about 13% and 196%, respectively, compared to neat LDPE. This was due to the observed enhancement in the interfacial adhesion between the fiber and matrix. The impact resistance and hardness of the composite enhanced by 55.28% and 26%, respectively, over neat LDPE. According to SEM analysis, the alkali treatment affected the morphology of fibers.

Ameliorated polyvinylidene fluoride based proton exchange membrane impregnated with graphene oxide, and cellulose acetate obtained from sugarcane bagasse for application in microbial fuel cell

Polyvinylidene fluoride (PVDF) based, Cellulose acetate (CA), and Graphene oxide (GO) doped membrane acts as a superior cost-effective cation exchange membrane (CEM) for the energy extraction application using microbial fuel cells (MFCs). In this study, the waste sugarcane bagasse was used to prepare CA, and the Tour method was used to prepare GO. CA and GO compositions were varied to prepare CEMs WCA-1, WCA-2, WCA-3, and WCA-4. Doping the functionalized GO material in the hydrophilic membranes enhances the contribution of conducting phase concerning its hydrophilic nature and facilitates its functional characteristics at the surface. Further, adding an adequate amount of GO improves the physicochemical properties of the membrane and its mechanical stability. Also, with the fusion of GO in the membrane, the trend for water uptake ability significantly increases. Post sulfonating the prepared membranes the enhancement in the attained proton conductivity values from 0.025 Scm-1 for WCA-1 to 0.4 Scm-1 for WCA-4 was observed, which may be attributed to the increase in the GO content in the prepared membranes. Among various prepared membranes, WCA-3 was considered for MFC application. The WCA-3 membrane outperformed several membranes for wastewater treatment and energy extraction using MFC. Columbic efficiency (CE) of 7.1%, chemical oxygen demand (COD) removal efficiency of 97.5 ± 0.8%, and power density of more than 150.22 mW m−2 were achieved without any electrode modification. Thus, the prepared low-cost novel PVDF-based, GO and CA membrane (WCA-3) elucidated its appropriateness for proliferating the efficacy of MFC and is recommended for scaling up of MFCs.

Eco-friendly incorporation of sugarcane bagasse ash as partial replacement of sand in foam concrete

The sugarcane bagasse is locally utilized in sugar industries for power production that yields a huge amount of dumped waste sugarcane bagasse ash, which poses threats to human health by mutilating the atmosphere through particulate matter. Besides, river sand resources are depleting worldwide due to the uncontrolled extraction of sand for concrete production. Therefore, this research presents the microstructural, fresh, physicomechanical, and thermal properties of bagasse ash incorporated foam concrete and its comparison is made with control foam concrete. Microstructural characterization includes morphology, oxide composition, chemical reactivity, and its crystallographic characteristics. The characterization results revealed that it has flaky, tubular, and irregular-shaped particles containing amorphous silica and thus, possesses pozzolanic reactivity. The results of physicomechanical and thermal properties of 10% sugarcane bagasse ash incorporated foam concrete mix produced the maximum increase in compressive strength of 14.50% and a decrease in thermal conductivity of 10.76% compared to control-mix. The rise in compressive strength of sugarcane bagasse ash-based foam concrete was due to the formation of secondary calcium silicate hydrate gel due to the formation of pozzolanic hydrates. Whereas the decreased thermal conductivity was due to lightweight bagasse ash. Contrarily, the higher replacement of sugarcane bagasse ash changes the pore size and shape, which consequently damages the distribution of the pores by imploding foam bubbles due to the adsorptive nature of sugarcane bagasse ash. Conclusively, sugarcane bagasse ash provides eco-friendly sand replacement in foam concrete without degrading its mechanical properties. • Sugarcane bagasse ash poses threats to human health by mutilating the environment. • Densification of foam concrete microstructure occurred upon sugarcane bagasse ash incorporation. • Mechanical properties of foam concrete improved due to micro-pore refinement in cement paste matrix. • Thermal conductivity of concrete mixes reduced due to low specific gravity of incorporated ash.

Facile preparation of sugarcane bagasse-derived carbon supported MoS2 nanosheets for hydrogen evolution reaction

Increasingly, future energy conversion systems highly demands non-noble metal catalysts with high activity and low cost for hydrogen evolution reaction (HER). This paper reports the use of waste sugarcane bagasse (SCB)-derived biomass carbon (SCBC) to synthesize carbon-supported molybdenum disulfide (MoS2) nanosheets for HER activity. The MoS2 nanosheets are uniformly loaded on the SCBC and show a vertical growth trend. Together, a synergistic effect was produced that impacted HER activity. The obtained MoS2/SCBC 2:1 showed admirable HER electrochemical activity, with a minimum overpotential of 142 mV at 10 mA cm−2, Tafel slope of 71 mV·dec-1 and Cdl value of 65.26 mF cm−2. The MoS2/SCBC 2:1 catalyst also exhibited high stability under acidic conditions. In conclusion, a non-noble metal electrocatalyst with low-cost and high-activity for HER from biomass waste has been provided for energy conversion system.

Microporous activated carbon developed from KOH activated biomass waste: surface mechanistic study of methylene blue dye adsorption.

In this work, sugarcane bagasse waste (SBW) was used as a lignocellulosic precursor to develop a high-surface-area activated carbon (AC) by thermal treatment of the SBW impregnated with KOH. This SBW activated carbon (SBWAC) was characterized by crystallinity, porosity, surface morphology and functional groups availability. The SBWAC exhibited Type I isotherm which corresponds to microporosity with high specific surface area of 709.3 m2/g and 6.6 nm of mean pore diameter. Further application of SBWAC as an adsorbent for methylene blue (MB) dye removal demonstrated that the adsorption process closely followed the pseudo-second order kinetic and Freundlich isotherm models. Conversely, a thermodynamic study revealed the endothermic nature and spontaneity of MB dye adsorption on SBWAC with high acquired adsorption capacity (136.5 mg/g). The MB dye adsorption onto SBWAC possibly involved electrostatic interaction, H-bonding and π-π interaction. This work demonstrates SBW as a potential lignocellulosic precursor to produce high-surface-area AC that can potentially remove more cationic dyes from the aqueous environment.

Novel supramolecular network of graphene quantum dots-vitamin B9-iron (III)-tannic acid complex for removal of chromium (VI) and malachite green

The present work is devoted to synthesize graphene quantum dots (GQDs) from waste sugarcane bagasse with average particle size 4.2 nm based on the TEM analysis. The produced GQDs were then aimed to combine with vitamin B9 (folic acid = FA) and Fe3+-tannic acid complex (Fe-TA) for the formation of a novel (GQDs@FA@Fe-TA) supramolecular network with average particle size 37.57 nm and pore diameter 38.35 nm. (GQDs@FA@Fe-TA) was evaluated as a multipurpose nanosorbent for removal of inorganic anionic (Cr(VI)) and organic cationic (malachite green, MG) pollutants from water. Cr(VI) removal was optimized as 99.5% (at pH 3.0 after 5 min), while 94.8% for MG (at pH 6.0 after 30 min). Adsorptions of both pollutants were exothermic and spontaneous and well explained with the pseudo-second order and Langmuir model. (GQDs@FA@Fe-TA) exhibited higher regeneration stability after five consecutive adsorption–desorption cycles (~2.1–4.3% loss). Finally, the potential applications of (GQDs@FA@Fe-TA) for removal of inorganic anionic and organic cationic pollutants from various water samples were 91.2–99.4% and 89.8–92.1% for Cr(VI) and MG, respectively.

Antibacterial and water-repellent cotton fabric coated with organosilane-modified cellulose nanofibers

Nosocomial infection from hospital garment contamination is an important issue in health institutes. Functional textile containing antimicrobial agents is one potential solution to eliminate bacteria on textile surfaces. Despite their advantages there are concerns that antimicrobial agents have a detrimental impact on the environment, therefore in this study we consider antimicrobial agents added to the surface of fibers that have minimal environmental concerns. Suspended nanocellulose – prepared by isolating cellulose fibers from sugarcane bagasse waste and then reducing their size to nanometer scale using a steam explosion machine and a high-pressure microfluidizer – was used as a coating material. The cellulose nanofibers modified with various organosilanes (in amino silane and quaternary ammonium silane form) were used as a modifying agent for improving antimicrobial and water-repellent behaviors of cotton fabric. This work indicates that octadecyldimethyl (3-trimethoxysilylpropyl) ammonium chloride at 0.25 % coating concentration is the ideal substance for antibacterial and water-repellent improvement with 99.99 percent bacterial reduction, 140 degree of water contact angle and no significant cellular toxicity.

Thickening Castor Oil with a Lignin-Enriched Fraction from Sugarcane Bagasse Waste via Epoxidation: A Rheological and Hydrodynamic Approach

Thickening vegetable oils to different extents is of great interest in the design and development of new bio-based lubricant formulations, as achieving a wide range of rheological properties is crucial to the successful replacement of petroleum-based traditional counterparts. With this aim, the influence of epoxidation degree, modified by altering the reaction conditions, on the viscous flow properties of epoxidized castor oil was investigated together with the incorporation of a lignin-enriched fraction from sugarcane bagasse waste to more extensively modify the rheological properties, thereby valorizing this waste fraction. Oil thickening was achieved by promoting the cross-linking between the epoxidized oil and the lignin-enriched fraction that enables the compatibilization of both components. Castor oil epoxidation was assessed by means of standard volumetric titration methods and infrared spectroscopy. In addition, a fully rheological characterization of both epoxidized and lignin-thickened castor oils was carried out. A hydrodynamic approach was also followed, aiming to provide an estimation of the Mark–Houwink–Sakurada parameters and relate the intrinsic viscosity with the average molecular weight of the resulting epoxidized castor oil/lignocellulose macromolecular compounds. The chemical interaction between castor oil and the lignocellulosic material increased as the extent of epoxidation was increased, yielding a variety of rheological responses from Newtonian liquids of increasing viscosities (from around 1 to 500 Pa·s) to viscoelastic liquids.

Waste sugarcane bagasse‐derived nanocatalyst for microwave‐assisted transesterification: Thermal, kinetic and optimization study

AbstractThe production of biodiesel has increased globally during the last decade to overcome the problems of increasing prices of petro‐diesel and the depletion of fossil fuels. The present study aimed to utilize agro‐waste sugarcane bagasse (SCB) to synthesize a heterogeneous acid catalyst for biodiesel production using waste cooking oil. Waste sugarcane bagasse was converted into biochar through partial carbonization and activated via sulfonation by using acid solutions of different concentration i.e., 1M, 3M, 5M and concentrated sulfuric acid at a sulfonation temperature of 180 °C for 5 h. The prepared catalysts were characterized by using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), the Brunauer–Emmett–Teller (BET) technique, X‐ray diffraction (XRD), and the Carbon, Hydrogen, Nitrogen and Sulfur (CHNS) analyzer. The prepared catalyst exhibited an excellent surface area of 20.78 m2 g–1 and a total acid density of 3.94 mmol g–1. The biodiesel production process was optimized by varying reaction temperature from (40–70 °C), methanol to oil molar ratio (5:1–20:1), catalyst loading (1–7 wt.%) and reaction time (5–25 min) by using a microwave reactor. The maximum conversion of 95.45% and yield of 92.12% was obtained under optimum conditions: catalyst loading 5 wt%, methanol‐to‐oil molar ratio (15:1), temperature (60 °C) after 15 min. The results of the experiments were validated by using response surface methodology, which validated the predicted model. The kinetic study of experiments showed that the use of sulfonated catalysts lowered the activation energy (10.5 kJ mol–1) and reactants attained an equilibrium point after a short interval under microwave heating. Reusability of catalyst up to seven cycles with 77.34% yield of biodiesel using low‐grade feedstock showed that the catalyst is stable and can be used for sustainable biodiesel production. The utilization of wastes for catalyst synthesis and for biodiesel production can help to minimize the overall production cost of biodiesel. © 2021 Society of Chemical Industry and John Wiley & Sons, Ltd

Modified Carbon Nanostructures Obtained from Sugarcane Bagasse Hydrochar for Treating Chromium-polluted Water

Background: Application of nanotechnology in wastewater treatment is the solution to cope with the conflict between people’s increasing demand for water and the world-wide water shortage. The main goal of this study is to prepare modified carbon nanostructures (CNSs) from sugarcane bagasse waste (SCB) as effective adsorbents for removing toxic Cr(VI) ions from their aqueous solutions. Methods: The preparation of CNSs was performed via catalytic hydrothermal/carbonization of SCB. The resultant CNSs sample was oxidized by oxidation with HNO3/H2O2 (O-CNSs) and then followed by coating with diethylenetriamine (N-CNSs). Transmission electron microscope (TEM), scanning electron microscope attached to energy-dispersive X-ray (SEM/EDX), fourier transform infrared (FTIR) and nitrogen adsorption analyses were used to determine the morphology and surface properties of CNSs. Adsorption and desorption studies of Cr(VI) ions onto these modified CNSs were investigated. Effects of initial concentration of Cr(VI), pH of solution and temperature in the batch mode were estimated. Adsorption studies were analyzed by Langmuir, Freundlich and Dubinin- Radushkevich models. Pseudo-first-order, pseudo-second-order and intraparticle diffusion models were undertaken to follow the adsorption mechanism. Results: The prepared samples composed of carbon nanotubes and graphene sheets were evident by TEM and SEM. The adsorption of Cr(VI) is exothermic in nature, well-fitted with Langmuir, described by pseudo-second order kinetic model and then is uncontrolled by intraparticle diffusion step. It was found that the adsorption of Cr(VI) was higher uptake over O-CNSs (56 mg/g) than that by NCNSs (44 mg/g). This was ascribed to that the first sample is enriched with acidic O-functional groups and possessed higher specific surface area (188 m2/g). Desorption studies were achieved by HNO3 and NaOH reagents for recovering the Cr(VI) from O-CNSs. Results revealed that about 90% of Cr(VI) can be recovered by HNO3 more than that by NaOH till the third run. Conclusions: Two modified CNSs samples were successfully prepared from SCB. Adsorption of Cr(VI) is highly relied on initial concentration of Cr(VI), pH and temperature. The main factors controlling the adsorption behavior of Cr(VI) are the acidic functional groups and the accessible surface area on O-CNSs. Furthermore, the O-CNSs attained high stability in recycling tests for Cr(VI) removal.