Agricultural Waste Materials Research Articles

Harnessing waste for sustainable construction: A novel synthesizing activators from waste for one-part geopolymer concrete and evaluating its fracture toughness

Geopolymer concrete garners significant attention due to its potential to mitigate pressing global challenges, such as CO2 emissions and waste management for disposal. However, using more expensive commercial activators has posed a significant obstacle to practical implementation. Therefore, scientists want to develop methods to extract powdered activators from agricultural and industrial waste materials. To this end, the study has sought to create innovative activators derived from waste glass powder (WGP) and silica-rich rice husk ash (RHA) to create one-part geopolymer concrete (OPGC). Ground granulated blast-furnace slag is utilized as a precursor material for preparing binder, with varying ratios of WGP/RHA to sodium hydroxide (NaOH) from 0.50 to 1.75 at 0.25 intervals. Twenty-four distinct mixtures of OPGC were prepared using the materials mentioned above and evaluated for their compressive strength and fracture toughness. The primary objective of this research is to evaluate the mode I, III, and I/III fracture toughness of OPGC using edge-notched disc bend specimens. Additionally, a 1 % steel fiber dosage was introduced into the OPGC to reduce brittleness. The microstructural characteristics were examined through X-ray diffraction and scanning electron microscopy. Findings reveal that the fracture toughness of OPGC improves with the RHA to NaOH ratio up to 1.0, peaking at 1.09 MPa·m^0.5. Likewise, the fracture toughness increases with the WGP to NaOH ratio up to 0.75, reaching a peak value of 1.20 MPa·m^0.5. Beyond these respective ratios, a decrease in fracture toughness was observed. Nonetheless, incorporating fibers into OPGC consistently improved the fracture toughness across all mixtures. Mode I fracture toughness is greater than I/III and III, emphasizing the significance of Mode III compared to other fracture modes.

New insights into the remediation of chromium-contaminated industrial electroplating wastewater by an innovative nano-modified biochar derived from spent mushroom substrate: Mechanisms, batch study, stability and application

To enhance the adsorption and detoxification capabilities of hexavalent chromium (Cr(VI)) using agricultural spent mushroom substrate (SMS), this study pioneered the preparation of biochar (NBC) from Lentinus edodes spent substrate. Subsequently, nano iron sulfide (FeS) particles were integrated onto NBC with carboxymethyl cellulose (CMC) as a stabilizer, resulting in a novel composite biosorption material, nFeS-BC. The adsorption and reduction potential of both NBC and nFeS-BC against Cr(VI) were evaluated through batch experiments, which identified pH as a critical factor influencing adsorption efficiency. Remarkably, nFeS-BC exhibited a superior maximum adsorption capacity (qmax) of 99.57 mg g−1 and a reduction efficiency of 68.65%, outperforming NBC by 277.73% and 211.76% under optimized conditions, respectively. Characterization techniques including Scanning Electron Microscopy-Energy Dispersive X-Ray (SEM-EDX), Fourier Transform Infrared Spectroscopy (FT-IR), and X-ray Photoelectron Spectroscopy (XPS) elucidated the removal mechanisms, predominantly attributed to ion exchange, electrostatic attraction, functional group interaction, and redox reaction. The carbon-oxygen functional groups and nano particles were crucial in the adsorption and reduction processes. Compared with NBC, the incorporation of FeS particles increased the specific surface area and pore volume of nFeS-BC by 130.86% and 183.77%, respectively. nFeS-BC owned a shelf-life of up to ∼3 months of use and exhibited excellent performance in the processing of actual electroplating wastewater with q of 16.71 mg g−1 under 0.1 g L−1 dosage. These findings underscore the potential of nFeS-BC as an efficient material for Cr(VI) removal, presenting a novel adsorbent for the sustainable detoxification of contaminated water resources and the potential for using agricultural waste materials in environmental remediation.

Sugarcane Bagasse Based Adsorbents and their Adsorption Efficacy on Removal of Heavy Metals from Nakuru Industrial Wastewater: Optimization, Kinetic and Thermodynamic Aspects

Currently, researchers are seeking to reduce heavy metal contamination from the environment, using agricultural waste materials like rice husk, groundnuts shells among others. The study focused on the removal of Cu(II), Pb(II), Cd(II), Ni(II), and Cr(III) ions from aqueous solutions and Nakuru industrial wastewater using sugarcane bagasse (NSCB) and valorised bagasse ash (VSCB), as alternative low-cost agricultural waste bio-sorbents. To achieve this goal, sugarcane bagasse was collected from Nzoia sugar industry in western Kenya, while the valorised bagasse was obtained by heating sugarcane bagasse sample in a muffle furnace at 300°C for three hours. Furthermore, batch adsorption studies were performed, and the effects of several factors, i.e. adsorbent particle size, pH, contact time, initial heavy metal ions concentration and temperature were investigated to optimise the removal efficiency of Pb, Cu, Cd, Ni, and Cr. The optimal adsorption conditions were pH of 5.0, adsorbent dosage of 0.1 g and ≤ 150µm particle size, equilibrium time of 60 minutes and at 25 degrees Celcius. The removal kinetics of the metal ions onto both adsorbents fitted well with the pseudo-second-order model. The removal kinetics of the metal ions onto both adsorbents fitted well with the pseudo-second-order model. The adsorption of Pb2+ and Ni2+ onto NSCB fitted better with the Freundlich isotherm model, while Cd2+, Cu2+ and Cr3+ showed better fit for the Langmuir isotherm model. As for VSCB adsorbent, Cr3+ has a better fit with the Langmuir isotherm model whereas Pb2+, Ni2+, Cd2+, and Cu2+ fitted well on the Freundlich isotherm model. Freundlich constant’s (1/n) values and the separation factor (RL) from the Langmuir isotherm model indicate that the metal ions were favourably adsorbed onto the adsorbents. Langmuir isotherm model was used to estimate the maximum adsorption capacities (qmax) for Cu(II), Pb(II), Ni(II), Cd(II), and Cr(III). The negative free energy change (∆G) values revealed that adsorption process of the metal ions onto NSCB and VSCB was spontaneous. Fourier Transform Infrared Spectroscopy (FTIR) was used for characterization studies. Interactions with metal ions caused the frequencies of the active functional groups, –OH, C=O and C=C, on the bio-sorbent surfaces to shift to higher values. Therefore, sugarcane bagasse and valorised bagasse have demonstrated higher potential to remove relatively all selected heavy metals in the industrial wastewater at controlled pH.

The role of rice husk in Oreochromis niloticus safety enhancement by bio-adsorbing copper oxide nanoparticles following its green synthesis: an endeavor to advance environmental sustainability

Lowering nanoparticles (NPs) toxicity before discharge into aquatic environments and employing agricultural waste materials for environmental sustainability are necessary nowadays. Since this has never been done, this work examines how green CuO NPs treated with rice husk (RH) as a bio-adsorbent may be safer for Nile tilapia (Oreochromis niloticus) than chemically manufactured ones. So, five groups of fish were randomly placed in glass aquaria. One group was a control, and four groups received 50 mg/L green and chemically produced CuO NPs (GS and CS) with and without RH for 24, 48, and 96 h. RH was collected from all groups, and the results showed GS-CuO NPs had a greater adsorptive capacity than CS-CuO NPs after all time intervals. After analyzing fish indicators in all groups compared to the control, higher Cu bioaccumulation was exhibited in the liver and gills. The liver and gills showed elevated levels of glutathione peroxidase (GPx), catalase (CAT), and thiobarbituric acid reactive substances (TBARS), while the levels of glutathione reduced (GSH) were significantly lower. In addition, Cu exposure impaired liver and gill histology. Finally, our results indicated that using RH as an adsorbent for CuO NPs after their green synthesis instead of chemical synthesis before they enter the aquatic environment can enhance the overall health of fish and environmental sustainability.

Taguchi-based grey relational analysis for multi-response optimization of the characteristics of HRAMMCs reinforced with agro-waste and SiC produced by ultrasonic-assisted bottom pour two-stage stir casting

Abstract This study aims to examine the impact of agricultural waste materials—specifically silicon carbide (SiC) and palm sprout shell ash (PSSA)—on the mechanical properties, including density, porosity, tensile strength, compression strength, impact strength, and hardness, as well as the tribological behavior of Al-Cu-Mg alloy-based HRAMMCs. Parametric optimization was conducted on HRAMMCs to predict the effect of input constraints on the performance of the composite, considering the weight percentage of SiC, PSSA, and ultrasonic-assisted stirring time. Taguchi’s L9 orthogonal array was used for the design of experiments (DOE), and the composites were fabricated accordingly. Their physical, mechanical, and tribological properties were determined experimentally. Taguchi-based Grey Relational Analysis for multi-optimization highlighted the potential of the HRAMMCs, with a density of 2.545 g cm−3, porosity of 5.810%, ultimate tensile strength of 341 MPa, flexural strength of 321 MPa, compressive strength of 394.016 MPa, Vickers hardness of 136.883 HV, wear rate of 6.88E-12 m3 m−1, and a coefficient of friction of 0.397. ANOVA shows that the developed mathematical model is a better fit for examining the impact of various factors on the GRG of and corresponding properties of developed HRAMMCs, Indicating the R2 value of the developed model is 99.33% (0.9933). The 2 wt% SiC, 2 wt% PSSA, and a stirring time of 7 min are optimal parameters for the present HRAMMCS; to reduce porosity, wear loss, and the coefficient of friction while increasing, ultimate tensile strength, compressive strength, and Vickers microhardness. Moreover, the examination of the tensile and impact fracture surfaces and worn surfaces was carried out using SEM analysis of the alloy and composite produced under the optimal experimental conditions. The results of the fracture surface analysis indicated that the failure of both tensile and impact fractures was due to an amalgamation of ductile and brittle behaviors. The composites exhibited lower ductility than that of the base alloys. A study of the wear mechanism revealed that it was a mixture of adhesive and abrasive wear mechanisms. The SiC and PSSA ceramic reinforcements demonstrate higher hardness compared to the alloy, which restricts the fluid-like movement of the matrix. When these reinforcements were added to the alloy, they substantially decreased the occurrence of severe delamination and the formation of adhesive wear particles.

Harnessing Bacillus safensis as biofertilizer for sustainable drought alleviation in Brassica juncea L

Carrier-based biofertilizers, which involve the introduction of plant growth-promoting bacteria into agricultural industry waste materials, are gaining increasing attention due to their profoundly positive impacts on soil health. In current study, various carriers, including dry leaves, sugarcane husk (SCH), rice husk (RH), and a combination/Mixture (MIX) of all three, were employed to support the bacterial strain, Bacillus safensis (SCAL1). This strain was utilized as a bioinoculant in the production of carrier-based biofertilizers. This particular strain was sourced from the Environmental and Microbial Botany Lab at Quaid-i-Azam University in Islamabad. Bacillus safensis strain exhibited notable improvements, evident in a high rate of longevity and larger colony-forming units within the carriers, as confirmed by measurements taken after 21 days of incubation. The drought stress was induced using polyethylene glycol solutions with concentrations of 15% and 25% administrated 6 and 15 days after germination, respectively. Four distinct biofertilizer types were formulated in the study: DL + SCAL1, RH + SCAL1, SCH + SCAL1, and MIX + SCAL1. When applied to Brassica juncea L. plants, all of these biofertilizers demonstrated the ability to mitigate drought stress and enhance the quality of Brassica juncea L. The immobilization onto SCAL1 by using SCH showed the best result compared to the liquid inoculum as carrier materials improve stability and shelf life. Furthermore, our results affirmed that carrier-based biofertilizers improved biochemical and physiological attributes of plants during drought conditions, highlighting their importance as a valuable resource for mitigating drought stress in Brassica juncea L. The findings revealed that carrier-based biofertilizers are an excellent source of diverse phytohormones, which are pivotal in alleviating drought stress.

Coupling of biochar and silicon for Phyto-management of Cd contaminated soil using Brachiariamutica

Contamination of soil with heavy metals is a threatening global environmental problem. With increasing urbanization, it is very important to design economical and environment-friendly mitigation measures to have pollutant free soil. Phytoremediation is an advancing technique to extract pollutants from soil to achieve eco-sustainability. This study aimed to investigate the combined impact of biochar and silicon on growth attributes of Brachiaria mutica grown in cadmium (Cd) contaminated soil. The biochar was prepared by co-pyrolysis of agricultural left-over biomass (rice husk, bamboo leaves and corn cob in a 1:1:1 ratio) and physio-chemical characters were studied by FTIR, SEM-EDX and proximate analysis. A pot study was conducted to evaluate the potency of biochar and silicon in lowering the Cd uptake by para grass grown under Cd spiked soil. Total 8 treatments were planned by taking 1 % and 2 % biochar with 0.01 % and 0.02 % silicon. The results have shown that treatment 8 (2 % biochar and 0.02 % silicon) exhibited maximum improvement in growth parameters such as shoot length by 2.64-fold and root length by 44.9 %, along with improving the antioxidant defense system of Para grass (CAT by 2-fold and POD by 56.4 %). Application of treatment 8 also decreased Cd concentration in the shoot and root by 48.8 % and 47.4 %, respectively. Treatment 8 was most effective in reducing CaCl2 extractable Cd in soil up to 56.1 %. Based on this data, treatment 8 was most effectual in suppressing Cd stress. Biochar produced from other agricultural waste material along with Si as inorganic amendment can be used to immobilize other toxic heavy metals at field level. Heavy metals immobilization potential of Si and biochar can be tested by harvesting other grasses and oil seed crop species.

EXPERIMENTAL EVALUATION OF EXPANSIVE SOIL STABILIZED WITH WHEAT HUSK ASH AND SISAL FIBER

Everything starts with soil. Being a civil engineer, we are aware of how essential soil is to construction, as everything is dependent on it. Before building any kind of structure on top of soil, we examine the soil's characteristics and behavior to determine its strength and ability to support the weight of the structure to be built on top of it. In this study work, we used agricultural waste materials, such as wheat husk ash (WHA), as a stabilized material in soil at different percentages of 5%, 10%, and 15% to perform various tests on the soil to determine its qualities or strength. Sisal fibers are inexpensive, readily available locally, and environmentally benign, making them an excellent choice for enhancing soil properties. The stabilizing effect of sisal fiber on soil characteristics has been experimentally investigated in this work. In light of this, an experimental study is carried out using pricey, locally accessible soil that has been blended with various percentages of sisal fiber. In the CBR mold and UCS sampler, soil samples are prepared at their maximum dry density (MDD) matching to their optimum moisture content (OMC) both with and without Sisal Fiber and WHA. In the laboratory, CBR and UCS tests are carried out in accordance with the proportion of Sisal Fiber by dry weight of soil, which is determined to be 1%, 1.5%, or 2%. According to test results, the amount of sisal fiber in the soil increases with its saturated CBR and UCS value. When wheat husk ash and sisal fiber are added, the CBR of the mix increases and the pavement thickness decreases, resulting in lower construction costs and ultimately, more economical highway building. Key Words: Compaction test, CBR, UCS, WHA, Sisal Fiber

Sustainable conversion of agricultural waste into solid fuel (Charcoal) via gasification and pyrolysis treatment

Managing agricultural waste by burning it in the fields is a straightforward method, but leads to significant pollution. One promising alternative is to convert agricultural waste into solid fuel, such as charcoal, to support renewable energy from biomass. The quality of barbecue charcoal depends upon selecting suitable materials and employing heating methods to ensure efficient transformation. This research aims to study the charcoal conversion process from agricultural waste using two types of kilns: 1) direct heating (gasification kiln: GK) and 2) indirect heating (pyrolysis kiln: PK) designed to recirculate syngas from wood as fuel for the pyrolysis process. The study tested three types of agricultural waste materials, including coconut shells (CS), cassava rhizome (CR), and acacia wood (AW), to examine the differences in charcoal produced by the two heating methods. The tests revealed that the maximum temperatures inside the kilns were 792.45 ± 127.18 °C, 907.67 ± 37.3 °C, and 980.07 ± 110.56 °C for the GK, and 921.88 ± 57.84 °C, 801.93 ± 10.16 °C, and 937.82 ± 95.85 °C for the PK. The charcoal from the PK exhibited higher calorific values than the GK, with 7474.68 ± 36.62, 6429.04 ± 72.22, and 7268.33 ± 52.86 calories per gram. The charcoal yield was also higher in the PK, at 31.29 ± 4.39, 34.33 ± 3.39, and 17.58 ± 2.09 percent for coconut shells charcoal (CSC), cassava rhizome charcoal (CRC), and acacia wood charcoal (AWC), respectively. However, the PK required more fuel and longer ignition times. The resulting charcoal from the slow pyrolysis process in the PK is suitable as barbecue fuel due to its size, which is similar to the original material. In contrast, the charcoal from the GK, which tends to shrink or break into smaller pieces, is more suitable for grinding into briquettes. This study provides a guideline for producing high-quality barbecue charcoal, offering commercial benefits including the gasification and pyrolysis processes that improve combustion efficiency and reduce pollution by producing high-quality gas for fuel, unlike traditional kilns that emit a large amount of CO during the conversion of wood to charcoal and enabling the selection of appropriate raw materials for different heating methods to maximise the utility of the products. This approach adds value to agricultural raw materials and helps effectively manage agricultural waste (zero waste) for further utilisation and development.

Novel sulfonic groups grafted sugarcane bagasse biosorbent for efficient removal of cationic dyes from wastewater

In this research, we reported the synthesis of effective sulphonated sugarcane bagasse (SCB@SA) biosorbent based on agriculture waste materials via a simple diazotization strategy for the removal of methylene blue (MB) and Bismarck Brown R(BB) dyes from waste water samples. First, the sugarcane bagasse (SCB) waste was collected, grinded, and sieved to obtain the desired size. Secondly, the SCB powder is modified with sulfanilinic acid (SA) via the formation of its diazonium salt to introduce sulfonic groups on the SCB surface. Different advanced techniques were applied to characterize the prepared materials before and after the adsorption process viz. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Energy-dispersive X-ray spectroscopy (EDS) and Thermogravimetric analysis (TGA). Different parameters affecting the adsorption process of both MB and BB were studied. Because of the higher correlation coefficient (R2 ≥ 0.999) and lower error functions, the equilibrium MB and BB adsorption isotherms for a single-dye system fit Langmuir with maximum adsorption capacity reaching to 127.48 and 166.75 mg/g for MB and BB, respectively. Moreover, the RL values obtained for both dyes lie between 0 and 1, indicating that MB and BB adsorption by SCB@SA is a favorable process. Besides, the error functions’ values of the pseudo-2nd-order are significantly lower than those of the pseudo-1st-order, implying that the adsorption MB and BB onto SCB@SA biosorbent fitted the pseudo-2nd-order kinetic model in a chemosorption manner. In the thermodynamic studies, the adsorption process is spontaneous, exothermic, and has less randomness. In addition, the SCB@SA biosorbent could be reused in five cycles maintaining on suitable adsorption efficiency. Finally, the MB and BB dyes could be adsorbed on the SCB@SA biosorbent via three mechanisms including π-π stacking, columbic attraction, and hydrogen bonding.

Mesoporous carbon particles by biomass waste based on sulfonation and copper oxide functionalization as efficient and stable electrode material for supercapacitor.

Here, the hierarchical mesoporous-activated carbon particles obtained by KOH activation from pistachio shell wastes are modified by both the sulfonation process and CuO doping by hydrothermal heating (CuO@S-doped PSAC) for use as a supercapacitor. It is predicted that the electrochemical performance of the porous carbon electrode material obtained by such CuO doping and sulfonation process will be significantly increased with increased Faradaic capacitance. The electrochemical performance of CuO@S doped PSAC composite is systematically investigated by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and galvanostatic charge/discharge (GCD) in the presence of 1M H2SO4, 1M Na2SO4, and 1M NaOH as electrolytes. The CuO@S doped PSAC-based electrode shows excellent stability with high specific capacitance up to 397.16 F/g at 0.1 A/g and 92.64% retention. Furthermore, FTIR, SEM, XRD, EDS, and nitrogen adsorption/desorption analyses are used for the characterisation of the obtained composites. Based on a significant supercapacitor performance, the synthesis strategy of carbon-based electrode material containing sulfonation and CuO modifications derived from agricultural biomass waste material is predicted to be a valuable example.

Synthesized ZnO nanoparticles using Sorghum Panicle for the photocatalytic degradation of pharmaceutical waste water

Sorghum Panicle, an agricultural waste material, contributes to air pollution when burned, causing health hazards. This research focuses on green synthesizing ZnO nanoparticles from Sorghum Panicle for Photocatalytic degradation, Antibacterial, and Phytotoxicity applications. The nanoparticles underwent surface and optical, morphological, structural, thermal, and zeta potential analyses. The Plasmon peak appeared at 381 nm, and XRD analysis revealed a crystallite size of 59.49 nm. Stability was confirmed via FTIR and Zeta potential analyses. FESEM analysis showed spherical particles sized 50–90 nm, aligning with XRD results. EDX analysis verified the presence of zinc and oxygen. TGA and DSC analyses demonstrated thermal stability. Paracetamol, a common painkiller, was used as a model pollutant. At pH 8, a 15 ppm nanoparticle concentration achieved a 90–95 % removal efficiency at 20 °C with 150 rpm agitation under UV light. The antibacterial study included both gram-positive and gram-negative bacteria. The Phytotoxicity study, using mung beans, showed a 100 % seed germination rate with treated water, indicating high efficiency.

Evaluation of carbonized cotton stalk for development of novel form stable composite phase change materials for solar thermal energy storage

Generating energy from the renewable sources is a pathway to attain sustainable energy systems. Utilizing bio-char produced from pyrolysis process as porous material would not only add great value to the waste discards, but also contributes towards enhancing the thermal properties. This work is focussed on the development of form stable phase change material (FSPCM) through a facile impregnation method by introducing cotton stalk biochar (CSB) as porous matrix along with polyethylene glycol having molar mass 10000 g/mol (PEG10000) as PCM. Cotton stalk is an agriculture waste material and biochar was produced by intermediate pyrolysis method at 550 °C. Thermal, chemical and surface characterization tests were executed on seepage free FSPCM (BCPCM4) as it showed no leakage at 60 °C. XRD, FTIR, FESEM, TGA, DSC, Raman spectroscopy and BET analysis were carried out to characterize thermal, chemical and surface properties of BCPCM4. The microporous structure of CSB was able to accommodate 80 wt% of PEG10000. Surface characterization tests demonstrated that adequate amount of PEG10000 was absorbed into the pores of CSB and the crystal structure of PEG10000 was not modified. The results of TGA illustrated that BCPCM4 was thermally stable. Additionally, cotton stalk derived FSPCM displayed high heat transfer rate which indicates an increase in thermal conductivity. To substantiate thermal reliability, 500 thermal cycles were run on BCPCM4 and about 1 % variation in latent heat has been noticed with meagre change in chemical properties. Therefore, biochar derived FSPCMs would serve as promising materials to accommodate solar thermal energy.

Evaluating the effectiveness of heavy metals removal from mine wastewater using agricultural waste materials

Polluted water bodies pose a danger to both aquatic and terrestrial lives, and recent development in the mining centre has escalated this pollution through the disposal of its industrial wastes. The objective was to investigate the potential of four different agricultural waste materials in eliminating the heavy metals from mine wastewater. The results show that the best performance in terms of adsorption capacity and removal efficiency was observed with coconut husk-activated carbon. The Arsenic (As) concentration decreased from 3.185 mg/kg to 1.570 mg/kg, and the Mercury (Hg) content decreased from 0.0307 mg/kg to 0.0064 mg/kg. The corresponding removal efficiencies were 51% for Arsenic and 79% for Mercury after 120 minutes of contact time at a speed of 250 rpm. The results suggest that coconut husk-activated carbon exhibited superior adsorption capacity and removal efficiency compared to the other agricultural waste materials (maize cob, rice husk, and sawdust). This indicates that the natural properties of coconut husk are more effective in removing heavy metals from mine wastewater.

Diclofenac sodium and paracetamol removal with ZnCl2 activated carbon produced from rice straw

This study explored the efficacy of activated carbon derived from rice straw and treated with ZnCl2 (ZnCl2-RS) for the removal of diclofenac sodium (DCF) and paracetamol (PCM) through an adsorption process. The investigation included examining the variations in removal efficiency at different pH levels and ZnCl2-RS doses. The characteristics of the ZnCl2-RS, prepared for the study, were determined through SEM and FTIR analyses, revealing a composition of 49.4% carbon and 8.3% zinc. At pH 5, the adsorption efficiency for DCF and PCM was enhanced, achieving removal rates of 92.2% for DCF and 89.1% for PCM with 0.2 g of ZnCl2-RS. The adsorption of DCF and PCM by ZnCl2-RS followed pseudo-second-order kinetic and adhered to the Langmuir isotherm model. The maximum adsorption capacities were calculated as 26.04 mg/g for DCF and 19.05 mg/g for PCM. In conclusion, the cost-effective production of activated carbon from agricultural waste like rice straw yielded a promising adsorbent material for efficiently removing pharmaceuticals such as diclofenac sodium and paracetamol. This approach not only contributes to waste reduction but also promotes the repurposing of agricultural waste materials.

Carbonized black pepper spike and its alginate composite for effective batch and column adsorption of uranium from water

The United Nations Sustainable Development Group (UNSDG) mandates clean water as one of its goals for 2030. In this context, we have adopted a sustainable pathway using black pepper spike, an agricultural waste material to synthesise a novel, eco-friendly adsorbent (Black Pepper spike Carbon, PPC) through microwave induced carbonization (MWI) for remediation of uranium from ground water. This material was also suitably modified into its calcium alginate composite beads (PPA) and used for fixed-bed column adsorption study. The physico-chemical properties of the adsorbents were analyzed using various analytical and spectroscopic methods. A maximum adsorption capacity of 333.33 mg g−1 was obtained for PPC from Langmuir model. The column variables were evaluated and an adsorption capacity of 191.5 mg g−1was realized with PPA using the Thomas model. With good selectivity and regeneration capacity, the adsorbents synthesized in this work provide a sustainable solution towards effective remediation of uranium from environmental water samples as an application study.

Production and Characterization of Activated Carbon Derived from Costus Afer Leaves (C. afer) for the Adsorption of Methylene Blue Dye from an Aqueous Solution

In this work, Costus afer leaves (C. after) was utilized as an agricultural waste material for the synthesis of activated carbon (AC) used for the adsorption of methylene blue dye from its aqueous solution. The raw material was prepared, chemically activated using KHCO3 with an impregnation ratio of 1:3, and later carbonized at a temperature of 700℃ in an inert N2 atmosphere for 1hour to produce activated carbon. The proximate analysis of the biomass revealed the percentage of ash content, moisture content, volatile matter, and fixed carbon present in the waste biomass. The raw and activated carbon produced were characterized using various tests such as: Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray (EDX), Fourier Transform Infrared-(FTIR) Spectrometry, X-Ray Fluorescence (XRF), and Brunauer-Emmett-Teller (BET). The results revealed that the SBET of the biomass increased from 400m2/g to 600m2/g after activation. Adsorption studies were carried out in batch mode to determine the influencing factors of adsorption with varying adsorbent dosage, contact time, and pH values. The adsorption experiment revealed high adsorption efficiency at an optimum parameter of dosage (0.2g), contact time (10 min), and pH (8) with a 70.58% removal of methylene blue dye. An increase in dosage, contact time, and pH above the optimum parameter leads to a decrease in percentage removal. The adsorption capacity was achieved using adsorption isotherm models like Langmuir and Freundlich. Adsorption of methylene blue validated the Langmuir model with an R2 of 0.999 and a Qm of 11.83 mg/g. These results show that activated carbon prepared from Costus afer leaves constitutes an effective low-cost material for the adsorption of Methylene dye from wastewater.

Bio-based composite active film/coating from deccan hemp seed protein, taro starch and leaf extract: Characterizations and application in grapes

This study aimed to create a novel, cost-effective, and environmentally friendly food packaging film or coating using agricultural waste materials such as deccan hemp seeds and leaves. The process involved blending deccan hemp seed protein and leaf extract at an optimal ratio through a casting technique. Additionally, starch isolated from taro root was added into the protein-based film to enhance its structural, barrier, and mechanical properties. The introduction of bioactive compounds, like deccan hemp leaf extract, led to increase in antioxidant activity and enriching the film with beneficial phenolic compounds.The combination of leaf extract and starch with the protein film resulted in a homogeneous, dense, and smooth film matrix, as evidenced by scanning microscopy images. FTIR spectroscopy confirmed interlinkage among the various constituents in the film. Rheological analysis of the film-forming solution showed its shear-thinning behavior, with the storage modulus exceeding the loss modulus in the angular frequency range of 0.1 rad/s to 100 rad/s, indicating the film's elastic nature. Furthermore, the physical and optical attributes of the films were enhanced through the addition of starch and leaf extract.In a practical application, the film-forming solution was applied to grapes, leading to improved quality and extended shelf life for grapes stored under ambient conditions for ten days. Overall, this study's findings suggest that the use of deccan hemp seed protein-based packaging film holds promise as an emerging solution for enhancing the shelf life of vegetables and fruits, offering a sustainable and effective alternative for food packaging.

Towards a natural treatment for mania: red onion husk extract modulates neuronal resilience, redox signalling, and glial activation

BackgroundRed onion husk, a readily available agricultural waste material, contains diverse bioactive compounds with potential health benefits. This study aimed to assess the safety and therapeutic potential of red onion husk extract in managing manic-like symptoms and associated neurochemical dysfunctions.MethodsAcute and repeated oral dose studies were conducted in mice and rats to evaluate the safety profile of the extract. FT-IR analysis identified functional groups in the extract, while GC-MS analysis identified specific bioactive compounds in the flavonoid-rich fraction. A ketamine-induced manic behaviour model in Wistar rats was employed to assess the extract’s efficacy in attenuating manic-like symptoms. Behavioural and neurochemical analyses were performed to further investigate the extract’s effects.ResultsThe extract demonstrated a favourable safety profile in both acute and repeated dose studies. FT-IR analysis revealed a complex mixture of organic compounds, including hydroxyl groups, alkynes/nitriles, aromatic and non-aromatic C = C bonds, amines, and polysaccharides. GC-MS analysis identified 17 bioactive compounds, including five-methyl-2-phenylindolizine, methadone N-oxide, and 3-phenylthiane, S-oxide. Ketamine administration significantly increased oxidative stress markers, TBARS, and suppressed antioxidant enzyme activities (SOD, GPx, CAT) in both the cerebral cortex and hippocampus, alongside elevated acetylcholinesterase (AchE) activity, indicating enhanced neuronal excitability. Pre-treatment with FRF (25 mg/kg) effectively mitigated ketamine-induced oxidative stress, as evidenced by reduced TBARS levels and partially restored SOD and GPx activities. Interestingly, FRF significantly increased CAT activity (p < 0.001), potentially suggesting an additional compensatory mechanism. Notably, FRF pre-treatment also counteracted ketamine-upregulated AchE activity, offering neuroprotection against heightened neuronal excitability.ConclusionRed onion husk extract exhibits a favourable safety profile and exerts potent antioxidant and neuroprotective effects, possibly through modulating Nrf2 signalling pathways. Its ability to counteract ketamine-induced oxidative stress and neuronal hyperactivity highlights its potential as a complementary therapeutic strategy for managing manic episodes in bipolar disorder. Further research is warranted to elucidate the precise molecular mechanisms underlying FRF’s action and explore its clinical efficacy in human studies.

KOH-Activated Dragon Fruit Peels for Cd2+ Ions Adsorption from Water

This study investigates the potential of KOH-activated dragon fruit peels as an adsorbent for the removal of Cd2+ ions from solution. The adsorption performance of the activated dragon fruit peels was evaluated through batch adsorption experiments, where various parameters including adsorbent dosage, initial Cd2+ concentration, contact time, and solution pH were examined. The optimum condition for the adsorption process was pH 5, stirring time 120 min, adsorbent dosage of 20 mg (in 25 mL solution). The findings highlight the potential of utilizing agricultural waste materials, such as dragon fruit peel, as an effective and sustainable adsorbent for the removal of heavy metal ions from water sources, contributing to environmental remediation efforts.