Stalk Waste Research Articles

Thermal Fabrication of Magnetic Fe3O4 (Nanoparticle)@Carbon Sheets from Waste Resources for the Adsorption of Dyes: Kinetic, Equilibrium, and UV–Visible Spectroscopy Investigations

Thermal treatment is applied for the direct conversion of palm stalk waste to Fe3O4 (np)@carbon sheets (Fe3O4 (np)@CSs). The effect of conversion temperature was investigated. The TEM examination of the prepared magnetic Fe3O4 (np)@CSs showed the formation of Fe3O4 (np) in a matrix of carbon sheets as a coated layer with surface functional groups including carbonyl and hydroxyl groups. Removal of dyes such as methyl orange, methylene blue, and neutral red was achieved using fabricated Fe3O4 (np)@CSs which were prepared at 250 °C, 400 °C, and 700 °C in a weak acidic medium. By studying the contact time effect for the adsorption of methylene blue, neutral red, and methyl orange, using the fabricated Fe3O4 (np)@CSs which were prepared at 250 °C and 400 °C, equilibrium occurred between 120 min and 180 min. In addition, the first-order and second-order kinetic models were applied to the adsorption data. The results revealed that the adsorption data fit better with the second-order kinetic model. Furthermore, the Freundlich model was found to be more suitable for describing the process of the separation of the dyes onto Fe3O4 (np)@CSs which were prepared at 250 °C and 400 °C, suggesting heterogenous surfaces and multi-layer adsorption.

Functionalization of Screen-Printed Electrodes with Grape Stalk Waste Extract-Assisted Synthesized Silver and Gold Nanoparticles: Perspectives of Electrocatalytically Enhanced Determination of Uranyl Ion and Other Heavy Metals Ions.

Recently, nanotechnology and nanoparticles (NPs) such as AgNPs and AuNPs have become important in analytical chemistry due to their great potential to improve the performance of electrochemical sensors. In this work, Ag and Au nanoparticles have been synthesized using a green route in which a grape stalk waste extract is used as a reducing agent to obtain metallic nanoparticles. These NPs were used to customize the surface of commercial screen-printed electrodes (SPCNFEs). The spin-coating method was used to modify commercial SPCNFEs under a nitrogen atmosphere. The resulting electrodes were used in a determination study of Cd(II), Pb(II), and U(VI) with differential pulse anodic stripping voltammetry (DPASV). The customized green AgNPs and AuNPs electrodes presented higher sensitivity and electroanalytical performance than the non-modified SPCNFE. The results showed that the best analytical parameters were obtained with the green, silver nanoparticle SPCNFEs, with a LOD of 0.12 μg L-1 for Pb(II), which is a lower value compared to the most restrictive regulation guidelines. Additionally, the U(VI) ion was successfully determined using the developed G-AgNPs-SPCNFE in spiked tap water, showing comparable results with the ICP-MS technique.

Novel edible films of pectins extracted from low-grade fruits and stalk wastes of sun-dried figs: Effects of pectin composition and molecular properties on film characteristics

This study aimed to explore the characteristics of novel fig pectin films. For this purpose, films of crude fig pectin (CFP) extracted from low-grade sun-dried fruits and films of crude (CSP) and purified (PSP) stalk pectins extracted from stalk waste of processed high-quality sun-dried figs were evaluated for their physicochemical properties. The properties of pristine (CFP, CSP, and PSP films) and CaCl 2 cross-linked films (CFP–Ca ++ , CSP-Ca ++ and PSP-Ca ++ films) of fig pectins were also compared with films of commercial citrus (CP and CP-Ca ++ ) and apple (AP, AP-Ca ++ ) pectins. The cross-linking improved the mechanical strength and barrier properties of most films. CP, CP-Ca ++ , PSP, and PSP-Ca ++ films showed greater mechanical strength and stiffness than other films. PSP-Ca ++ , PSP and CP-Ca ++ films showed the lowest water vapor permeability (6.28, 12.85, 14.96 g.mm.m −2 .day −1 .kPa −1 , respectively) while CSP-Ca ++ , CP-Ca ++ , CP, PSP-Ca ++ films showed the lowest oxygen permeability coefficients (5403, 8265, 10776, 11124 ml.μm.m −2 .24h −1 .atm −1 , respectively). All cross-linked fig pectin films showed 2–3 fold lower degree of swelling than CP-Ca ++ film. The CFP-Ca ++ film showed the highest surface hydrophobicity (contact angle = 101.8°) but the lowest water solubility (32.8%) and degree of swelling. Analysis of Pearson's correlations between pectin properties and film characteristics revealed that galacturonic acid (GA) content affects the mechanical properties, while GA content, degree of esterification (DE), and acetylation affect the moisture barrier performance; finally, GA content and DE affect the oxygen barrier performance of pectin films. Films of stalk waste pectins showed some properties beyond the limits of those obtained from commercial pectins. • Pectins were extracted from low-grade fruits and stalk wastes of sun-dried figs. • Mechanical and barrier properties of fig and commercial pectins were compared. • Cross-linking of films improved their mechanical and barrier properties. • Stalk waste pectin films showed the highest moisture and gas barrier properties. • Pectin composition was correlated with film properties for the first time.

Potential of Corn Stalk Biomass as Biosorbent in Adsorption of Mercury (Hg) Metal Contaminants

Corn stalks are an agricultural waste that is commonly found in Indonesia. Corn stalks have a high enough cellulose content which has functional groups that can be used as biosorbents. This study aims to optimize the adsorption of corn stalk waste to mercury metal ions and then determine the adsorption capacity and adsorption constant of the Langmuir and Freundlich isotherm model. This research begins with corn stalk preparation, delignification, characterization using FTIR and SEM, determination of optimization of biosorbent weight, pH of Hg solution, contact time, and concentration of Hg solution, then applied to mercury metal contamination waste. Optimization of the weight of biosorbent in the range 0.4-1.2 grams, pH of the Hg solution is 2-4, contact time is 60-120 minutes, and concentration of the Hg solution of 30-100 g/L with a solution volume of 50 mL. Furthermore, determination of mercury levels, manufacture of standard series, and testing using ICP-OES. Followed by the determination of Langmuir and Freundlich's adsorption isothermal model. The results of this study indicate that the optimum conditions for the adsorption process occur at the weight of the biosorbent 1.2 grams, pH of the Hg 3 solution, contact time of 90 minutes, and concentration of Hg solution of 40 ppb with a solution volume of 50 mL. The application of biosorbent to metal contamination waste with adsorbed Hg concentration obtained 27.5772 ppb in 50 mL of waste solution with an adsorption efficiency of 88.44%. In the determination of Langmuir and Freundlich isotherms, a match was found for Langmuir adsorption isothermals with an adsorption capacity of 0.00333 mg Hg/g biosorbent and b = 176.8256.

Sustainable waste cotton and pigeon pea stalk fibers composite materials for acoustics and thermal properties

This study focuses on the development and characterization of pigeon pea stalk/cotton fibers mixed with a blend ratio of 50/50, 70/30, 30/70, 60/40, 100/0 waste cotton and 0/100 waste pea stalk composites are equipped with a compression molding system. The entire composite samples are tested for acoustics, thermal and physical parameters as per the American Society for Testing and Materials standard (ASTM). The sound absorption coefficients (SAC) were measured according to ASTME1050 by an impedance tube method, and the SAC over six frequencies 125, 250, 500, 1000, 2000, and 4000 Hz were calculated. The result revealed that the composite samples that are prepared from cotton/pigeon pea waste have confirmed more than 80% of the SAC and the waste composites provided the best insulation, sound absorption, moisture absorption, and fiber properties. The effect exposed that composites materials arranged from cotton/pea stalk waste fiber have established further than 75% by the sound immersion measure and the waste 28% composites handed the fashionable Appropriation, sound immersion, humidity immersion, and fiber materials. The waste cotton/pigeon pea stalk composite samples have satisfactory moisture resistance at high humidity situations without disturbing the insulation properties.

Characterization of Natural Fiber Extracted from Corn (Zea mays L.) Stalk Waste for Sustainable Development

Corn stalk fibers were extracted from corn stalk using sodium hydroxide for textile application. The extraction conditions were optimized on the basis of the quality and quantity of extracted fibers. The optimum conditions were obtained by treating corn stalk with 5 g/L concentration of sodium hydroxide for 60 min at boiling temperature using a 1:50 material-to-liquor ratio. Extracted fibers were bleached and tested for different physical and chemical properties. Besides these properties, the characterization of extracted fibers was carried out by a scanning electron microscope (SEM), X-ray diffraction analysis (XRD) and Fourier–transform infrared (FTIR) analysis. SEM was used to study the morphological changes in the raw and bleached fibers. The crystallinity changes of the raw and bleached samples were measured with an X-ray diffractometer by peak height method. FTIR was used to examine the compositional changes in the bleaching process. It was found that raw fibers contained the cellular residues such as lignin and hemicelluloses, which cement the fibers together. The chemical treatments such as alkali and bleaching partially removed hemicelluloses, lignin, and amorphous fractions of cellulose. This led to the gradually increasing crystallinity of the treated fiber. Peak height values were obtained by measuring the transmittance of the spectra through FTIR analysis. Different physical and chemical properties of the extracted corn stalk fibers indicated that it can be used for making biodegradable composite materials.

Brinjal (Solanum melongena) stalk waste as an effective scavenger for Eriochrome Black-T from water and wastewater: an approach towards waste to best

Stalks of brinjal (Solanum melongena), hereinafter SM, have been exercised as an efficient and sustainable adsorbent material for the elimination of Eriochrome Black-T (EBT) from an aqueous solution. The material was characterized by FTIR, FESEM, BET surface area, pHpzc, and proximate analysis. FTIR spectrum suggests the presence of polyphenolic moieties, responsible for successful dye binding. FESEM images show an unprecedented octopus-like texture containing micropores. The central head transforms the architecture of a flower. The evaluated BET surface area of 10.042 m2/g and pore volume 1.055 × 10−2 cm3/g suggest a porous material. The pHpzc of the material was evaluated to be 7.05, and under optimized conditions, the maximum adsorption capacity was found 52.631 mg/g at pH 7. The operational parameters were studied concerning contact time (0–90 min), pH (5–11), initial concentration (10–40 mg/L), and interfering ions (PO4 −3, AsO4 −3, Hg+2, Pb+2). Adsorption follows Langmuir isotherm best (R 2 = 0.996), and pseudo-second-order kinetics (R 2 = 0.991) indicate a monolayer and homogeneous adsorption. 83% regeneration was successful with 0.1(M) sodium hydroxide solution. The material can be reused for up to three cycles with 90% efficiency retention. Analysis of EBT containing industrial effluent indicates that 52.62% of EBT can be removed.

Coated Particleboards based on Castor Stalk Waste as an Alternative to Artificial Wood: (Part II)

Coated Particleboards based on Castor Stalk Waste as an Alternative to Artificial Wood: (Part II)

Effects of Pleurotus pulmonarius stalk waste extract‐supplemented feed on the immune responses of red hybrid tilapia Oreochromis sp. following challenge with pathogen‐associated molecular patterns

Intensive farming of red hybrid tilapia Oreochromis sp. significantly increases the emergence of infectious diseases. Recently, dietary administration of functional feed additives is gaining popularity as an alternative to antibiotics and chemotherapeutics. Mushroom stalk waste (MSW), which possesses the same therapeutic effects as the fruiting body, has immense potential as a cost-effective feed additive in aquaculture. In the present study, 10 g/kg of the ethanol-pretreated hot water extract (E-HWE) of Pleurotus pulmonarius stalk waste was supplemented in the feed of red hybrid tilapia for a 30-day period to determine the effects on growth performance and immune activation after challenging the fish with pathogen-associated molecular patterns (PAMPs). Results showed that E-HWE supplementation significantly improved (p < 0.05) the feed conversion ratio, protein efficiency ratio and hepatosomatic index in red hybrid tilapia but had no apparent effect on the growth. Upon PAMPs challenge, the phagocytic activity and respiratory burst activity of blood leukocytes were significantly enhanced (p < 0.05) in E-HWE-supplemented group. E-HWE supplementation also resulted in significantly higher (p < 0.05) serum haemolytic activity and bactericidal activity. All immune-related genes investigated were upregulated in E-HWE-supplemented group; il1b, tnfa and tlr3 revealed higher expression levels at day 1 post-PAMPs challenge, while ighm and tcrb genes expression levels were elevated after 3 days PAMPs challenge. This study revealed that E-HWE could be a promising and cost-effective feed additive in red hybrid tilapia farming which may also provide a solution for MSW disposal.

Biosorption of Cu(II) ions as a method for the effective use of activated carbon from grape stalk waste: RMS optimization and kinetic studies

ABSTRACT This study was undertaken to examine the effect of such biosorption factors as initial Cu(II) concentration, biosorbent dosage, reaction temperature, contact time and mixing speed on the efficiency of removal Cu(II) ions from wastewater using activated carbon from grape stalk waste. In this case, Response Surface Methodology (RSM) was used in conjunction with a Box–Behnken design of experiments to predict the final Cu(II) concentration (CFin ), while considering the previously mentioned biosorption factors. In an attempt to obtain the maximum removal of final Cu(II) concentration, while minimizing energy consumption, the Multi-Response Surface Methodology (MRS) was used. Three possible optimizations were proposed for the maximum elimination of final Cu(II) in this case. The maximum (100 mg/L), minimum (2 mg/L) and intermediate (51 mg/L) values of the study were used for the initial Cu(II) concentration. The optimal values that were reached were 92.21% when the initial copper concentration was 51 mg/L and the activated carbon dose, temperature, mixing speed and reaction time, were, respectively, 0.895 g/L, 20.036°C, 105.313 rpm and 30.181 s. Also, in regard to thermodynamic studies, the experimental equilibrium data provided a good fit using the Freundlich model, whereas the kinetic data were efficiently by the pseudo-second order. These results support the use of grape stalk waste in the production of activated carbon for the removal of Cu(II) ions from water. This could help to improve the economics of treating wastewater.

The Use of the Artificial Neural Network (ANN) for Modeling of Thermogravimetric Curves of Tobacco Stalk Waste Exposed to Alkaline Treatment

ABSTRACT Tobacco is a rich source of cellulosic material and one of the most cultivated non-food plants in the world with great potential for incorporation in polymeric matrices. The use of tobacco residues as reinforcing filler requires chemical/physical fiber treatment aiming to maximize compatibility with the polymer. In this study, tobacco residues were treated with two concentrations of NaOH (10 or 15 wt.%) at two-time exposures (3 or 5 h). Four distinct heating rates were used for each condition. It was applied an artificial neural network to model the thermogravimetric curves. After, the fitted ANN curves were used to create a 3D surface response. The equations from 3D surface response allowed the creation of thermogravimetric curves in any heating rate situated between the minimum and maximum range tested.

Effect of used different growing media on soilless lettuce cultivation

This study investigated the effects of reusing the growing media (TSW; tomato stalk waste, PTSW; pretreated tomato stalk waste, Peat + Perlite, Cocopeat) used in soilless agriculture on soilless lettuce cultivation. Significant effects of growing media on stem diameter, root length, total dry weight, yield, titratable acidity, SSC and Vitamin C values of lettuce (Maritima) grown without soil were determined (p<0.05; p<0.01). As a result of the highest root length (33.63 cm), total dry weight (27.22 g) and yield (558 g plant -1 ) were obtained from TSW medium. The highest titratable acidity values (1.05 g 100 mL -1 ) and Vitamin C (391.6 mg 100 g -1 ) were obtained from PTSW medium. It has been determined that TSW and PTSW media can compete with commercial growing media, especially in terms of yield and quality. The second use of the growing medium created from tomato waste significantly reduced the production costs. As a result, it has been determined that tomato waste (TSW) is a good alternative in terms of productivity and profitability instead of commercial growing medium.

Uniform rod and spherical nanocrystalline celluloses from hydrolysis of industrial pepper waste (Piper nigrum L.) using organic acid and inorganic acid

Conversion of lignocellulosic biowastes from agricultural industry into nanocrystalline cellulose provides pathway to reduce environmental pollution while enhancing the economic value of biowastes. Nanocellulose (NCC) with uniform morphology was isolated from pepper (Piper nigrum L.) stalk waste (PW) using acid hydrolysis method. The role of inorganic acids (sulfuric acid, hydrochloric acid, phosphoric acid), organic acids (oxalic acid, citric acid, acetic acid) and variation of sonication times were investigated on the physicochemical characteristics, self-assembled structure, crystallinity, particle size, zeta potential and thermal stability of the isolated nanocellulose. Hydrolysis using inorganic acids transformed cellulose from PW into a spherical shaped NCC at ~33–67 nm of average diameter. Meanwhile hydrolysis in organic acids produced rod-shaped NCC at 210–321 nm in length. This study highlighted the role of acidity strength for organic acid and inorganic acid in controlling the level of hydrogen bond dissociation and the dissolution of amorphous fragments, which consequently directing the morphology and the physicochemical properties of NCCs.

Procena fizičko-mehaničkih osobina kompozita poliester-kukuruz

In this study, corn stalk/polyester composites were prepared using molding techniques at several percentage filler loadings per weight and the physiomechanical properties were studied. The composite showed moderate improvement in tensile strength 13.582MPa for 3% corn stalk which was the highest. The composite also reported the highest values for impact strength 744.90(J/m2 ) and flexural strength 23.947MPa, respectively for filler loading of 3% corn stalk and 93% polyester and 2% corn stalk and 98% polyester composite samples. The significant strengths recorded can be attributed to the good surface intermingling bonding between the corn stalk fillers and the polyester matrix. The study also revealed that, density of the composites decreased with increase in filler loading and the density dropped from 0.116 g/cm3 to 0.108g/cm3 . The composites recorded increase in water uptake with increasing filler loading. The results showed that the highest water absorption rate was at 5% corn stalk loading which had maximum water absorption of 4.55% by the composite samples. The physiomechanical properties of the composites indicate that it can be useful in applications which require moderate strengths. These composites could be considered as a potential way of utilizing agricultural waste materials and as sustainable resources for manufacturing of structural materials such as particle board, partitioning panels, ceiling boards thereby reducing the amount of agricultural wastes and eliminating the pollution caused by burning of corn stalk waste.

Equilibrium, kinetics, and optimization studies of methylene blue removal from aqueous solution using corn stalk wastes

Equilibrium, kinetics, and optimization studies of methylene blue removal from aqueous solution using corn stalk wastes

Valorization of Hemp Stalk Waste Through Thermochemical Conversion for Energy and Electrical Applications

The presented research aimed at finding new ways to value hemp by-products (stalks) from the cannabidiol industry through thermochemical conversion. Chemical and elemental composition of hemp biomass was investigated by successive chemical extractions and Scanning Electron Microscopy along with Energy-dispersive X-ray Spectroscopy. Proximate and elemental analyses completed the chemical characterization of the hemp biomass and its biochar. Thermogravimetric analysis of the hemp biomass allowed to understand its kinetic of decomposition during thermal conversion. The carbon structure and porosity of the biochar were assessed by Raman spectroscopy and CO2 gas adsorption. Properties of interest were the energy production measured through calorific values, and the electrical conductivity. Two ways of valorisation of the hemp biomass were clearly identified, depending mainly on the chosen pyrolysis temperature. Hemp biochar carbonized at 400–600°C were classified as lignocellulosic materials with a good potential for solid biofuel applications. Specifically, the resulting carbonized biochar presented low moisture content (below 2.50%) favourable for high fuel quality, low volatile matter (27.1–10.4%) likely to show lower particle matter emissions, limited ash content (6.8–9.8%) resulting in low risk of fouling issues during the combustion, high carbon content (73.8–86.8%) suggesting strong energy density, associated with high higher heating values (28.45–30.95 MJ kg−1). Hemp biochar carbonized at 800–1000 °C displayed interesting electrical conductivity, opening opportunities for its use in electrical purposes. The electrical conductivity was related to the evolution of the biochar microstructure (development of graphite-like structure and changes in microporosity) in regard with the thermochemical conversion process parameters.Graphical abstract

Valorization of Hemp Stalk Waste Through Thermochemical Conversion for Energy and Electrical Applications

Valorization of Hemp Stalk Waste Through Thermochemical Conversion for Energy and Electrical Applications

Eco-friendly and acid-resistant magnetic porous carbon derived from ZIF-67 and corn stalk waste for effective removal of imidacloprid and thiamethoxam from water

Neonicotinoids, extensively present in water environment, can adversely affect the ecological safety and human health. Herein, a low-cost magnetic porous carbon ZIF-67/CS@C derived from ZIF-67 and agricultural waste corn stalk (CS) is designed and applied for adsorptive removal of imidacloprid and thiamethoxam from water. The adsorbent is fabricated by carbonizing ZIF-67/CS hybrid pre-prepared through an in-situ decoration of ZIF-67 on the surface of CS, and then acid picking to elute the unstable constituents. In the carbonization, Co2+ ions are reduced to magnetic Co0 nanoparticles, with the result that ZIF-67/CS@C shows a strong magnetic response (saturation magnetization intensity is 12.25 emu‧g−1) and can be easily magnetically separated. Meanwhile, Co nanoparticles are protectively encapsulated in well-developed graphitized wall, which endows ZIF-67/CS@C with good acid resistance (only 0.23% of Co is leached out at pH 1.0). More importantly, reasonable pore size distribution (most pore sizes match or are 3–6 times that of imidacloprid and thiamethoxam) and high external surface area (280 m2‧g−1) are obtained, which makes ZIF-67/CS@C super adsorbent. The adsorption capacities for imidacloprid and thiamethoxam can reach as high as 189 and 133 mg‧g−1, respectively. Moreover, after six consecutive recycling processes, the adsorption efficiencies are still above 95%, which reveals excellent reusability of ZIF-67/CS@C. Mechanism analysis affirms that pore-filling, H-bond, and π-π EDA interaction are mainly responsible for driving imidacloprid and thiamethoxam adsorption. Finally, ZIF-67/CS@C with a great security towards Daphnia carinata survival and wheat growth is eco-friendly. This study can be easily adapted to different biomass wastes and MOFs, thus potentially enabling the preparation of more novel adsorbents.

Utilization of stalk waste separated during processing of sun-dried figs (Ficus carica) as a source of pectin: Extraction and determination of molecular and functional properties

This study aimed the utilization of fig stalk waste as an alternative pectin source. For this purpose, the characteristics of extracted stalk waste pectin (SP) were compared with those of citrus pectin (CP) and pectin extracted from defected substandard whole sun-dried figs (FP). The SP had a higher extraction yield (11.7%) than FP (9.4%). The galacturonic acid content and degree of esterification of SP (32.3 and 50.1%) were higher than those of FP (19.9 and 38.8%), but lower than those of CP (79.3 and 56.2%), respectively. The SP and CP had different sugar compositions (d-glucose, l-rhamnose, d-galactose and l-arabinose) and weight average molecular weights, but similar FTIR profiles. The SP showed almost 1.9 and 1.6-fold higher Trolox equivalent antioxidant capacity (TEAC), and 2.7 and 2.0-fold higher water absorption capacity than CP and FP, respectively. SP at 3% (w/w) showed the second highest viscosity after CP and the highest emulsion stability. Gels of SP and CP at 1.75–3% range had similar firmness, but SP formed more fracturable gels than CP. Sun-dried fig stalk waste is a better source of pectin than defected substandard whole sun-dried figs. The SP could be utilized to develop functional food with alternative textural and rheological properties.

Physicochemical Properties of Nanocellulose Isolated from Cotton Stalk Waste.

In recent years, nanocellulose has become an attractive and high-value-added product. The cotton stalk is a waste product with a high cellulose content. Therefore, nanocellulose can be isolated from the cotton stalk. Properties of nanocellulose are affected by its nanoscale. In this study, the characteristics of cellulose in nanoscale were investigated. A series of cotton stalk nanocelluloses were prepared by sulfuric acid hydrolysis to study their physicochemical properties and the differences of nanocelluloses on different nanoscales. The obtained nanocelluloses were analyzed by atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TA), and X-ray diffractometry (XRD). From the morphology analysis, the mean length and width of nanocelluloses were decreased to 90.5 and 7.0 nm, respectively. From the FTIR analysis, with the particle size decreasing, hydrogen bonds were broken and recombined. Acid hydrolysis mainly acted on intramolecular hydrogen bonds of cellulose macromolecules, especially on O(3)H···O(5) bonds. The crystal arrangement model of nanocellulose was investigated. From the TA analysis, the thermal property was decreased with a reduction of nanocellulose particle size. The CrI of the cotton stalk nanocellulose was the highest at up to 87.10%. The differences of cotton stalk nanocelluloses give significant changes to physicochemical behaviors at the nanoscale. The research would provide a theoretical basis for the future application of nanocelluloses.