Peanut Hulls Research Articles

Adsorption of hexavalent chromium from wastewater using magnetic biochar derived from peanut hulls

In this study, the utilization of peanut hulls as a precursor for the preparation of magnetic biochar through pyrolysis was investigated. To enhance the magnetic and adsorption properties of the biochar, the peanut hulls biomass was modified using ferric chloride hexahydrate and magnesium chloride hexahydrate. Response surface methodology was employed to evaluate the influence of biomass metal concentration, pyrolysis temperature, pyrolysis period and flow of nitrogen on the yield and Cr (VI) adsorption efficiency of the synthesized biochar. A 17-run experimental matrix was generated using Optimal Design to investigate the interactions among four input parameters. The results led to the development of a quadratic model, which demonstrated a high degree of predictability in accordance with the experimental data. Analysis of variance (ANOVA) confirmed that the models for yield and Cr (VI) adsorption efficiency were highly significant (p < 0.05), with coefficients of determination (R2) values of 0.891 and 0.988, respectively. The optimal synthesis conditions for producing biochar with superior physicochemical properties were identified as a pyrolysis temperature of 300 °C, a pyrolysis duration of 2 h, a metal-to-biomass ratio of 0.5, and a constant flow of nitrogen. A desirability of 85% was achieved through numerical optimization, corresponding to a yield of 63% and complete Cr (VI) removal. Further optimization of Cr (VI) adsorption efficiency, considering the effects of pH (3–12), adsorbent loading (1–15 g/L), and initial Cr (VI) concentration (5–20 mg/L), was performed using a 19-run experimental matrix. ANOVA for Cr (VI) adsorption efficiency model revealed high significance (p < 0.05) with an R2 value of 0.916.The magnetic biochar demonstrated a remarkable adsorption efficiency of 98% under the experimental conditions of solution pH 3, adsorbent dosage of 5 g/L, and an initial Cr (VI) concentration of 20 mg/L. The desirability of 100% was obtained by a numerical optimization method representing Cr (VI) removal of 98%. The adsorption behaviour was adequately described by the Freundlich isotherm model, suggesting multilayer adsorption, with a maximum adsorption capacity of 12 mg/g. Biochar also proved to have strong magnetic properties which enhanced solid-liquid separation post adsorption experiments.

Peanut Hull lignin/ecamsule·2Na hollow nanoparticles (P/E LNPs): A natural light-coloured, broad-spectrum, highly antioxidant, and safe lignin-based sunscreen

Lignin represents a potentially significant natural sunscreen alternative due to its good UV-absorbing ability, but its poor UVA absorption and dark colour are still obstacles. Numerous methods have been developed to whiten the colour of lignin, mainly including aromatic ring interruption and hydroxyl group blocking. However, these complicated procedures would weaken the UV-blocking and radical scavenging abilities. Here, we develop a strategy for the valorization of lignin in sunscreen to overcome their drawbacks by the in situ self-assembly of the natural light-coloured peanut hull lignin with the commercially available UV-protectant Ecamsule·2Na to obtain peanut hull lignin/Ecamsule·2Na hollow nanoparticles (P/E LNPs). The results show that the sun protection factor (SPF) value increased from 20 to 27, and the antioxidant capacity increased exponentially with a scavenging rate of up to 82 % at the extremely low dosage up to 0.1 mg/L of P/E LNPs. In addition, their good biocompatibility and safety were further confirmed by in vitro cytotoxicity analysis. In summary, we have successfully prepared a safe, broad-spectrum, light-coloured, and highly antioxidant, peanut hull lignin-based sunscreen that avoids any complicated chemical modifications to meet the commercial sunscreen requirement and also provides a new solution for the valorization of lignin from the vast amount of waste fruit hulls.

Transformation of agro industrial waste from peanut hulls as an innovative source for sustainable cellulosic dyeing and antimicrobial finish

Transformation of agro industrial waste from peanut hulls as an innovative source for sustainable cellulosic dyeing and antimicrobial finish

Utilizing biochars to stabilize mercury in contaminated floodplain sediment: Implications on mercury remediation.

Major weather events contribute to the mobility and remobilization of legacy mercury (Hg) contamination and sequestration within sediments. Remediation using biochar as a soil amendment is a useful technique to immobilize and decrease Hg toxicity. This study explored whether biochar application is effective at stabilizing labile mercury (LaHg) from floodplain sediment. Controlled mesocosms simulating contamination events and flooding conditions were conducted. Floodplain sediment, which experiences annual periodic flooding, was collected. Sediment was spiked with inorganic Hg, applied with different types of biochar, and experienced simulated flooding events. Four types of biochar, pure rice husk (RH), pure peanut hull (PH), sulfur-modified rice husk (SMRH), and sulfur-modified peanut hull (SMPH), were applied at 10 and 40g/kg rates (i.e., RH 10, RH 40; PH 10, PH 40, SMRH 10, SMRH 40, SMPH 10, SMPH 40). Total Hg, methylmercury, and LaHg concentrations were analyzed by coupling with redox potential measurements. Results indicate that SMRH 10, PH 10, PH 40, SMPH 10, and SMPH 40 successfully remediate Hg by stabilizing and reducing LaHg species from floodplain sediment. However, a high Hg methylation potential was observed with unsulfated and sulfated peanut hulls (PH 10, PH 40, SMPH 10, and SMPH 40), as they tend to create a reducing microenvironment that favors sulfate reduction reactions. Additionally, sulfur-modified biochar tends to promote Hg methylation potential at high application rates (i.e., 40g/kg). We thus recommend using SMRH at a relatively low application rate (SMRH 10) for the remediation of Hg from floodplain sediment.

Electron beam pretreatment of carboxymethyl nanofibrillar cellulose reinforced polyvinyl alcohol-based degradable composite membranes: Preparation, characterization and property optimization

This study investigated the development of biodegradable composite films blending carboxymethyl-modified peanut hull nanocelluloses (CMNCs) pretreated by electron beam irradiation with polyvinyl alcohol (PVA). The films were characterized by their structure, physicochemical properties, and degradation characteristics. The carboxyl group of CMNCs and the hydroxyl group of PVA enhance the network structure of the film through hydrogen bonding. This is most notably manifested in the fact that when CMNCs with a substitution degree of 0.38 and an addition amount of 4 % were added, the CMNCs were uniformly dispersed in the PVA matrix with a flat and smooth surface of the plastic and a dense structure. Meanwhile, the water contact angle (57.14°), the tensile strength (47.28 N/mm2) and elongation at break (156 %) of the composite films were significantly increased, and the water content (12.71 %) was decreased. The hydrophobic and mechanical properties of the composite plastics were improved considerably. In addition, the addition of 4 % CMNCs with a degree of substitution of 0.66 and a high dose of electron beam irradiation (120 KGy) to PVA made the degradation rate of the composite plastic in the first week (31 %) much higher than that of pure PVA (3 %). At the same time, the light transmittance of the composite plastic decreased significantly in both visible and UV ranges. EBI pretreatment significantly improved the degradation and light barrier properties of the composite plastics. Therefore, this study may provide new ideas for EBI pretreatment-assisted chemical modification of nanocellulose to prepare functional composite films.

Biochar impacts on carbon dioxide, methane emission, and cadmium accumulation in rice from Cd-contaminated soils; A meta-analysis

Climate change and cadmium (Cd) contamination pose severe threats to rice production and food security. Biochar (BC) has emerged as a promising soil amendment for mitigating these challenges. To investigate the BC effects on paddy soil upon GHG emissions, Cd bioavailability, and its accumulation, a meta-analysis of published data from 2000 to 2023 was performed. Data Manager 5.3 and GetData plot Digitizer software were used to obtain and process the data for selected parameters. Our results showed a significant increase of 18% in soil pH with sewage sludge BC application, while 9% increase in soil organic carbon (SOC) using bamboo chips BC. There was a significant reduction in soil bulk density (8%), but no significant effects were observed for soil porosity, except for wheat straw BC which reduced the soil porosity by 6%. Sewage sludge and bamboo chips BC significantly reduced carbon dioxide (CO2) by 7–8% while municipal biowaste reduced methane (CH4) emissions by 2%. In the case of heavy metals, sunflower seedshells-derived materials and rice husk BC significantly reduced the bioavailable Cd in paddy soils by 24% and 12%, respectively. Cd uptake by rice roots was lowered considerably by the addition of kitchen waste (22%), peanut hulls (21%), and corn cob (15%) based BC. Similarly, cotton sticks, kitchen waste, peanut hulls, and rice husk BC restricted Cd translocation from rice roots to shoots by 22%, 27%, 20%, and 19%, respectively, while sawdust and rice husk-based BC were effective for reducing Cd accumulation in rice grains by 25% and 13%. Regarding rice yield, cotton sticks-based BC significantly increased the yield by 37% in Cd-contaminated paddy soil. The meta-analysis demonstrated that BC is an effective and multi-pronged strategy for sustainable and resilient rice cultivation by lowering greenhouse gas emissions and Cd accumulation while improving yields under the increasing threat of climate change.

Green synthesis of highly pyrrolic nitrogen-doped biochar for enhanced tetracycline degradation: New insights from endogenous mineral components and organic nitrogen synergy

The synthesis of efficient and environmentally friendly persulfate (PS) catalysts is currently a prominent research focus. This study employs single-step carbonization to investigate the interactions between endogenous mineral components (EMCs) and N-doping of nitrogen-rich biomass, aiming to design efficient biochar-based catalysts for enhanced tetracycline (TC) degradation. Biochars (PBC and SBC) derived from peanut hulls (PH) and soybean curd residue (SCR) with similar EMCs (ash ratio 16:19) but varying nitrogen content (1 % vs 1.53 %) were achieved, along with melamine-N-doped PBC (PBCN) for comparison under identical conditions. Physicochemical and quantum-chemistry analyses were conducted to investigate the synergistic effects between EMCs and organic-nitrogen in terms of morphological structures, active sites, and catalytic persulfate (PS)-mediated degradation of TC. The findings revealed that the optimal synthesis temperature for the efficient biochar-based catalyst was 800 °C. In contrast to exogenous N-doping with higher N-content (7.81 %), organic-N accelerated lattice disruption, leading to enhanced interactions with EMCs and resulting in the formation of hierarchical structures and pyrrole-N (organic-N 43.44 % > exogenous-N 17.67 %). The SBC/PS system exhibited superior degradation capability, with rapid removal of 95 % in 100 mg·L-1 TC. Density functional theory (DFT) confirmed that the non-radical pathways including 1O2 and electron transfer, facilitated by the presence of CO and pyrrole-N, were responsible for binding PS and forming biochar-PS*. This study furnishes both experimental data and theoretical insights, supporting the targeted control and efficient advancement of eco-friendly, high-value biochar-based catalysts.

Efficient Removal of Cr(VI) from Wastewater by Magnetic Biochar Derived from Peanut Hull

Efficient Removal of Cr(VI) from Wastewater by Magnetic Biochar Derived from Peanut Hull

Peanut hulls, an underutilized nutritious culinary ingredient: valorizing food waste for global food, health, and farm economies-a narrative review.

Peanut hulls (PHs) are an edible food waste that is an underutilized food source for human consumption. While edible and palatable, currently they are mainly diverted to livestock feed or building materials. Here, we describe existing literature supporting human food valorization of PHs, and propose methods to optimize recapturing nutrients (protein, fiber, phenols and other phytonutrients) lost by treating PHs as waste. Incorporated into common foods, PHs could be processed into functional ingredients to improve nutrient-density with anticipated corresponding positive health outcomes associated with increases in plant foods. Valorization of PHs addresses multiple priorities of the UN Sustainable Development Goals using a Food Systems Approach (FSA) including reducing food waste, increasing economic opportunities for farmers, and increasing the availability of healthy shelf-stable foodstuffs to address food security. Recent advances in sustainable food processing technologies can be utilized to safely incorporate PHs into human food streams. We propose future applications that could make meaningful impacts for food availability and the nutritional composition of common foods like bread and plant-based meat alternatives. While the limited literature on this topic spans several decades, no commercial operations currently exist to process PHs for human consumption, and most literature on the topic precedes the technological "green revolution." The approaches outlined in this review may help bolster commercialization of this underutilized and nutritious food potentially improving opportunities for multiple global stakeholders.

Development and utilization of raw and NaOH-modified peanut hull as potential adsorbents for crystal violet dye removal from wastewater

Development and utilization of raw and NaOH-modified peanut hull as potential adsorbents for crystal violet dye removal from wastewater

Peanut Hulls, Swine Feces, and Silver Carps: Eating, Excreting, and Communal Metabolism in 1950s Guangxi

Peanut Hulls, Swine Feces, and Silver Carps: Eating, Excreting, and Communal Metabolism in 1950s Guangxi

333 Using Specific Bacillus Strains to Improve Digestibility and Performance of Growing Steers

Abstract Low fiber digestibility is an important factor restricting the growth performance of cattle in the dry tropics, both during the initial growth phase in grazing systems and later during finishing in high-starch diets. Due to concerns relating to the non-therapeutic use of antibiotics, including ionophores, there is interest in replacing these with probiotics. The objective was to evaluate the effects of specific strains of Bacillus spp. (Bovacillus, Chr. Hansen, Denmark) on intake and total tract nutrient digestibility of two diets. The first diet was forage based [100% Rhodes grass hay with 69% neutral detergent fiber (NDF)], the second was a high-energy diet (20% Rhodes grass hay, 40% finisher pellet, 30% peanut hull fiber pellet, 10% ground barley, 47% NDF, 18% starch). Twelve Bos indicus steers (267 ± 7.5 kg) were blocked by initial body weight and randomly assigned to receive the diets either without probiotic supplementation (n = 6, Control) or the diets plus 3 g per head of a probiotic containing a mixture of Bacillus licheniformis and Bacillus subtilis (3.2 x 109 CFU/g) for the duration of the trial. Each diet was fed for a 34-d period in individual pens followed by a 7-d sampling period during which the steers were housed in metabolism crates for total collection of urine and feces. On the high-fiber diet, supplementing with the probiotic increased organic matter digestibility by 7.8% (49.9 vs. 53.8%) and NDF digestibility by 8.4% (49.7 vs. 53.9%) resulting in greater (P &amp;lt; 0.05) digestible fiber intake (1.62 vs. 1.72 kg/d). There was no effect of probiotic supplementation on intake or digestibility in the high starch diet, and Bacillus supplements did not change rumen microbial protein synthesis in both diets. In conclusion, supplementing steers with a Bacillus-based probiotic has the potential to improve the nutrient digestibility and performance of beef steers, especially in tropical grazing systems.

The Inhibiting Effects of High-Dose Biochar Application on Soil Microbial Metagenomics and Rice (Oryza sativa L.) Production.

Biochar is usually considered as an organic improver which can improve soil and increase crop yields. However, the unrestricted application of biochar to normal-fertility farmland will cause chemical stress on crops and affect agricultural production. At present, the effects and mechanisms of high-dose applications of biochar on rice (Oryza sativa L.) production and soil biological characteristics have not been fully studied. In this greenhouse pot experiment, combined with soil microbial metagenomics, three treatments in triplicates were conducted to explore the responses of rice production, soil chemical properties, and soil biological properties to high-dose applications of biochar (5%, w/w) prepared using peanut waste (peanut hulls and straw). The results show that peanut hulls, with a loose texture and pore structure, are a raw material with stronger effects for preparing biochar than peanut straw in terms of its physical structure. In a rice monoculture system, high-dose applications of biochar (5%, w/w) can slightly increase the grains per spike, while significantly inhibiting the spike number per pot and the percentage of setting. High-dose applications of biochar also have significant negative effects on the diversity and stability of soil bacterial and archaeal communities. Moreover, the microbial metabolism and nutrient cycling processes are also significantly affected by changing the soil carbon/nitrogen ratio. This study discusses the response mechanisms of rice production and soil biology to high-dose biochar applications, and complements the understanding of irrational biochar application on agricultural production and land sustainability.

Synthesis and characterization of peanut hull modified chitosan beads.

The incorporation of plant materials is an effective method to improve the stability of chitosan beads, as it further increases the adsorption of toxic dyes and metals from aqueous systems. In the present study, chitosan gels were impregnated with a novel type of powder as the groundnut hull powder in order to form composite beads by using a simple droplet-based microfluidic system. The beads were then characterised through various techniques such as SEM, TGA, FTIR, and XRD. Microscopic imaging revealed a change in the surface morphology of the composite beads, which became rough and wrinkled with more valley-like features and irregular cracks. FTIR data suggest that the impregnation of groundnut hull powder led to an increase in functional groups. The thermal analysis allowed for the assessment of composite bead hydration contents and indicated the presence of groundnut hull entrapped in the loaded beads, which was corroborated by vibrational spectroscopy. XRD analysis allows us to conclude that there is an involvement of groundnut hull in the chitosan gels, and the consequence of that is the formation of amorphous beads, which would make them suitable for the adsorption of toxic dyes and metals from water systems.

A Comparison between High-Performance Countercurrent Chromatography and Fast-Centrifugal Partition Chromatography for a One-Step Isolation of Flavonoids from Peanut Hulls Supported by a Conductor like Screening Model for Real Solvents.

Peanut hulls (Arachis hypogaea, Leguminosae), which are a side stream of global peanut processing, are rich in bioactive flavonoids such as luteolin, eriodictyol, and 5,7-dihydroxychromone. This study aimed to isolate these flavonoid derivatives by liquid-liquid chromatography with as few steps as possible. To this end, luteolin, eriodictyol and 5,7-dihydroxychromone were isolated from peanut hulls using two different techniques, high-performance countercurrent chromatography (HPCCC) and fast-centrifugal partition chromatography (FCPC). The suitability of the biphasic solvent system composed of n-hexane/ethyl acetate/methanol/water (1.0/1.0/1.0/1.5; v/v/v/v) was determined by the Conductor like Screening Model for Real Solvents (COSMO-RS), which allowed the partition ratio KD-values of the three main flavonoids to be calculated. After a one-step HPCCC separation of ~1000 mg of an ethanolic peanut hull extract, 15 mg of luteolin and 8 mg of eriodictyol were isolated with purities over 96%. Furthermore, 3 mg of 5,7-dihydroxychromone could be isolated after purification by semi-preparative reversed-phase liquid chromatography (semi-prep. HPLC) in purity of over 99%. The compounds were identified by electrospray ionization mass spectrometry (ESI-MS) and nuclear magnetic resonance spectroscopy (NMR).

Efficiently catalytic degradation of tetracycline via persulfate activation with plant-based biochars: Insight into endogenous mineral self-template effect and pyrolysis catalysis

Endogenous mineral of plant such as potassium, calcium and iron may play a crucial role in boosting the physicochemical structure and catalytic activity of high temperature pyrolyzed plant-based biochar while it is often neglected owing to its relative less content. Herein, self-template pyrolyzed plant-based biochars were prepared from two different ash-contained agricultural wastes of peanut hull (PH, 3.2% ash) and cotton straw (CS, 0.8% ash), and aimed at investigating the relationship among the endogenous mineral fractions of plant-based biomass, physicochemical active structure and persulfate (PS) catalytic degradation activity for tetracycline (TC). The results of energy/spectral characterization showed that under the self-template effect and pyrolysis catalysis of endogenous minerals, PH biochar (PBC) possessed much more specific surface area, conjugated graphite domain, C=O and pyrrolic-N surface active functional sites than CS biochar (CBC), enhancing TC removal rate of PBC/PS to 88.37%, twice that of CBC/PS (44.16%). Meanwhile, reactive oxygen quenching and electrochemical experiments showed that electrons transfer and non-free radical pathways based on singlet oxygen contributed 92% of TC removal in PBC/PS system. Remarkably, by comparing the differences in structure and TC removal performance of pre-deashing and non-deashing prepared plant-based biochars, a possible mechanism for endogenous mineral components' self-template effect and pyrolysis catalysis role of plant-based biomass was proposed. This study provides a new insight for revealing the intrinsic mechanism of mineral elements enhancing the active surface structures and catalytic properties of plant-based biochars derived from distinct feedstocks.

Removal of Methylene Blue from a residue as a low-cost biosorbent: peanut hull (Arachis hypogaea)

The textile industry is still very relevant for people’s everyday life and their production of goods, however, throughout the production chains, there are impacts on the environment, such as the elimination of effluents with the presence of dyes used in the production processes. These substances can cause environmental contamination if untreated, and the proper treatment for them is adsorption. This technique, although efficient, has a high cost, which favors the use of natural adsorbents, especially the usage of abundant residues in the environment. Therefore, this paper aims at using an agro-industrial residue, peanut hulls, produced on a large scale, as an adsorbent in the treatment of wastewater using the dye methylene blue. The Bel® SPECTRO S-2000 UV-visible spectrophotometer at a wavelength of 664 nm was used to analyze the absorbance of the dye concentrations. These data were used in the construction of the calibration curve, where the values found were calculated to obtain the adsorption capacity, which allowed us to identify the efficiency of the biosorbent. The results obtained were compared with the literature, and although the experiment had different conditions, the peanut hulls presented an adsorption capacity of 4.26925 mg/g, which represents an efficiency. Nevertheless, further studies are needed to carry out other analyses to evaluate the conditions that allow an increase in the adsorption capacity.

Experimental Investigations of the Removal of Methylene Blue from Waste Water using Agricultural Adsorbant

Abstract: The colored organic or inorganic chemical compounds which can impart colour to other substance are the Dyes which did significant applications in the most industrial sectors like the textile industry, leather industry, paper industry, plastic, foodstuff industry etc, to impart color to their products. Due to the large volume of dye use in these businesses, a significant quantity of wastewater containing colored organics is generated. Because of insufficient dye-fiber fixation, during the dyeing process, half of the dye is lost in the wastewater. Peanut and rice husk are used to absorb MB from water. Initial Methylene Blue concentration, Peanut and Rice Husk dose, and pH were monitored and compared to current adsorbents to identify the optimal removal conditions. The equilibrium amount of MB adsorbed at time t (min) for rice husk and peanut hull are obtained as 5.1 and 5.19 mg/g respectively. As part of the research, an intra-particle diffusion model was implemented to regulate the mass transfer model's rate-controlling step mechanism. Keywords: Waste Water, Methylene Blue, Peanut Hull, Rice Husk, Adsorption.

Experimental Investigations of the Removal of Methylene Blue from Waste Water using Agricultural Adsorbant

Abstract: The colored organic or inorganic chemical compounds which can impart colour to other substance are the Dyes which did significant applications in the most industrial sectors like the textile industry, leather industry, paper industry, plastic, foodstuff industry etc, to impart color to their products. Due to the large volume of dye use in these businesses, a significant quantity of wastewater containing colored organics is generated. Because of insufficient dye-fiber fixation, during the dyeing process, half of the dye is lost in the wastewater. Peanut and rice husk are used to absorb MB from water. Initial Methylene Blue concentration, Peanut and Rice Husk dose, and pH were monitored and compared to current adsorbents to identify the optimal removal conditions. The equilibrium amount of MB adsorbed at time t (min) for rice husk and peanut hull are obtained as 5.1 and 5.19 mg/g respectively. As part of the research, an intra-particle diffusion model was implemented to regulate the mass transfer model's rate-controlling step mechanism.

Interaction between biochar-dissolved organic matter and chlorophenols during biochar adsorption.

Biochar (BC) has been widely applied in the remediation of chlorophenols (CPs) from contaminated sites in which the role and mechanisms of BC dissolved organic matter (BDOM), as a crucial component of BC, with CPs are largely unknown and thus need to be investigated. In this study, DOM was derived from peanut hulls (PDOM) and corn stalks (CDOM) as BC sources, and the interactions between PDOM/CDOM and 2,4,6-trichlorophenol (TCP) were analysed using excitation-emission matrix spectroscopy (EEM) in combination with multiple models. EEM combined with fluorescence region integration (EEM-FRI) indicated that humic-like materials were the major materials of both PDOM and CDOM (percentage fluorescence response Ri,n > 60%), and CDOM contained more protein- and fulvic-like materials than PDOM. Based on EEM in combination with parallel factor analysis (EEM-PARAFAC), 4 components were obtained, and the percentage decrease in maximum fluorescence intensities (Fmax) showed that the main components interacting with TCP in PDOM/CDOM were protein- and fulvic-like components (> 25%). Moreover, the modified Stern-Volmer model was used to calculate the stability constants (Log KTCP) of PDOM/CDOM and TCP for the first time, and the mechanism of static quenching was dominant for interacting with TCP in PDOM (Log KTCP: 4.36-4.65) and CDOM (Log KTCP: 3.53-4.73). Furthermore, the sequential TCP binding of fluorescent components in BDOM generally followed the order of protein-like → short-wavelength fulvic-like → long-wavelength fulvic-like → humic-like components. These findings will provide a basis for screening biochar as a functional material for CP remediation applications and for understanding the environmental chemical behaviour of leached DOM during biochar application.