Rice Husk Powder Research Articles

Saccharification and co-fermentation of lignocellulosic biomass by a cockroach-gut bacterial symbiont and yeast cocktail for bioethanol production

BackgroundThe eco-friendly transformation of agro-industrial wastes through microbial bioconversion could address sustainability challenges in line with the United Nations’ Sustainable Development Goals. The bulk of agro-industrial waste consists of lignocellulosic materials with fermentable sugars, predominantly cellulose and hemicellulose. A number of pretreatment options have been employed for material saccharification toward successful fermentation into second-generation bioethanol. Biological and/or enzymatic pretreatment of lignocellulosic waste substrates offers eco-friendly and sustainable second-generation bioethanol production opportunities that may also contribute to waste management without affecting food security. In this study, we isolated a promising filamentous bacterium from the guts of cockroaches with commendable cellulolytic activity. The matrices of sequential statistics, from one-factor-at-a-time (OFAT) through significant variable screening by Placket-Burman design (PBD) to Box‒Behnken design of a surface methodology (BBD-RSM), were employed for major medium variable modeling and optimization by solid-state fermentation. The optimized solutions were used to saccharify lignocellulose in real time, and the kinetics of reducing sugar accumulation were subsequently evaluated to determine the maximum concentration of sugars extracted from the lignocellulose. The hydrolysate with the highest reducing sugar concentration was subjected to fermentation by Saccharomyces cerevisiae, Klyuveromyces marxianus and a mixture of both, after which the ethanol yield, concentration and fermentation efficiency were determined.ResultsSequential statistics revealed that rice husk powder, corn cob powder, peptone and inoculum volume were significant variables for the bioprocess at 59.8% (w/w) rice husk powder, 17.8% (w/w) corn cob powder, 38.8% (v/w; 109 cfu/mL) inoculum volume, and 5.3% (w/w) peptone. These conditions mediated maximum cellulolytic and xylanolytic activities of 219.93 ± 18.64 FPU/mL and 333.44 ± 22.74 U/mL, respectively. The kinetics of saccharification of the lignocellulosic waste under optimized conditions revealed two peaks of reducing sugar accumulation between 16 and 32 h and another between 56 and 64 h.ConclusionsAlthough K. marxianus had a significantly greater fermentation efficiency than S. cerevisiae, fermentation with a 50:50 (% v/v) mixture of both yeasts led to 88.32% fermentation efficiency with 55.56 ± 0.19 g/L crude bioethanol, suggesting that inexpensive, eco-friendly and sustainable bioethanol production could be obtained from renewable energy sources.

Two plant extracts protect stored maize against infestation of Sitophilus zeamais in Northern Ghana

Botanicals have been encouraged as substitutes for conventional pesticides to reduce the impact of the latter on the environment. In line with that, we studied the effects of two plant extracts in controlling Sitophilus zeamais Motsch (Coleoptera: Curculionidae) attacks on stored maize (Zea mays L. Poales: Poaceae). The experiment was conducted under a normal room temperature of 27⁰C to 30⁰C and relative humidity of 74% to 76% in a completely randomized experimental design. We infested the stored maize seeds in glass jars with S. zeamais F1 under a 12-hour day and 12-hour night within 24hours period. This was after 50g of the seeds were mixed with 2g each of the two botanicals separately in different glass jars. There were 5 treatments and 10 replications in total. The data taken for this study were quantitative. To ascertain the efficacy of the botanicals we compared the number of dead and live weevils, of seeds damage and weight loss caused by weevil attacks under each of the different treatments by determining percentage mortality, percent weight loss, seed damage and progeny production. Our results showed that the different botanical formulations significantly controlled S. zeamais population resulting in reduced damage, better protection and improved storage of maize seeds. However, there were no significant differences in protections offered between shade dried neem seed powder and rice husk powder although the latter was the most efficacious with 85% mortality compared to the former with 65% with sundried neem seed powder being the least with a little above 40% mortality. We concluded from this study that the formulated botanicals were very effective in controlling S. zeamais populations and therefore recommended that it be used as a cost effective and environmentally friendly protection of stored maize against S. zeamais attacks, especially in rural poor areas and places known for continuous seed production and storage, such as the case of the study community.

Eco-Friendly Innovation: Crafting Bio-Environmental Rice Husk Board for Sustainable Living

Background: The growing focus on environmental sustainability and safety has heightened the demand for eco-friendly household materials. This study explores the development of a bio-based board using rice husk (RH), assessing its properties and potential for diverse applications. Methods: The board was formulated using 30 g RH powder, 2 ml glycerol, 4 g agar, 3 g calcium propionate, and 100 ml water. The study involved visual and textural evaluation, physical property testing, and microbial growth assessment. Practical utility was examined through the fabrication of various objects including boxes and candle bases, and material adaptability was tested by varying RH concentrations and additives. Results: The RH boards, with equal proportions of RH and RH powder, exhibited light weight and good physical characteristics. Microbial growth was limited to 39% under conditions of 37 °C and 95% humidity. The boards were moldable, with a smooth, easily colorable surface post-sanding, demonstrating shape stability and flame retardancy under prolonged heat exposure. Furthermore, the material demonstrates good compatibility; varying RH ratios, colorants, and preservatives yield different appearance effects and characteristics. Conclusions: This study successfully developed a sustainable, safe, and versatile RH board, showcasing significant commercial potential and suitability as an innovative eco-friendly material.

Enhancement of alkaline pretreatment-anaerobically digested sludge dewaterability by chitosan and rice husk powder for land use of biogas slurry

Alkaline pretreatment can improve the methane yields and dewatering performance of anaerobically digested sludge, but it still needs to be coupled with other conditioning methods in the practical dewatering process. This study utilized four different flocculants and a skeleton builder for conditioning of alkaline pretreatment-anaerobically digested sludge. Chitosan was found to be the most effective in dewatering the sludge. Chitosan coupled with rice husk powder further improved the dewatering performance, which reduced normalized capillary suction time, specific resistance to filtration, and moisture content by 98.7%, 82.0%, and 12.1%. For land use of biogas slurry as a fertilizer, chitosan conditioning promoted the growth of corn seedlings, while the other three flocculants diminished the growth of corn seedlings. Chitosan coupled with rice husk powder further promoted the growth of corn seedlings by 103.5%, 65.0%, and 53.7% in fresh weight, dry weight, and root length, respectively. Overall, chitosan coupled with rice husk powder not only enhanced the dewaterability of alkaline pretreatment-anaerobically digested sludge but also realized the resource utilization of agricultural waste.

Effects of Mixed Microcapsules in Different Proportions on Aging Resistance and Self-Healing Properties of Waterborne Coatings for Tilia europaea L

In order to prolong the effective time of the self-healing properties of waterborne coatings containing shellac microcapsules coated with melamine rice husk powder (MRHP), three kinds of MRHPs with better microscopic morphologies, which contain 2.8% (type A), 5.5% (type B), and 8.0% (type C) of a rice husk powder (RHP), in shell materials were mixed according to three different proportions, and added to the waterborne coatings based on Tilia europaea L., under the conditions of the most proper addition amount of 6.0% microcapsules. The results indicated that the waterborne coatings containing mixed microcapsules can still maintain the best state in terms of optical properties and mechanical properties, with a chromatism of 1.10, an adhesion of zero, a hardness of 4H, an impact resistance of 7 kg·cm, and an elongation at break of 35.28%, respectively. According to the aging resistance test, the waterborne coating containing microcapsules “type A + type B + type C” demonstrated a longer effective time. After aging for 200 h in the UV climate resistance test chamber, the light loss rate at an incident angle of 60° was 2.91%. Through scratch testing, it is verified that the mixed microcapsules can prolong the self-healing time, reduce the crack size, and achieve a coating self-healing rate of 41.11%. They can also inhibit the crack growth rate to a certain extent. Roughness tests indicated that the surface roughness of the coating with mixed microcapsules increased by 0.038 μm in comparation with the single microcapsule, but the surface can still remain smooth after being covered by the topcoat without the microcapsules. Studying the ratio of mixed microcapsules provides new ideas for the optimization of a wood-based coating self-healing effect.

Sustainable cement mortar production using rice husk and eggshell powder: a study of strength, electrical resistivity, and microstructure

In order to preserve the natural fine aggregates and proper waste resources recycling, rice husk and eggshell powders were used as filler materials in production of standard M30 grade mortar. Natural fine aggregate was replaced with rice husk powder (RHP) at 3%, 5%, 7%, 10%, 12%, and 15%, and with eggshell powder (EP) at 3%, 5%, and 7%, both at a constant water-to-cement ratio of 0.40. Compressive strength, split tensile strength, water absorption, pore distribution, and electrical resistivity of the mortar samples were investigated. Also, XRD, SEM, and EDS were performed to observe the samples’ chemical phases and microstructure. The results show that up to 15% RHP reduced the compressive strength by 20–35%, whereas the up to 7% EP obtained a similar (varies by 0–5%) result compared to the control sample at 28 days. Furthermore, the results suggest that sand replacement with RHP and EP had no impact on the water absorption and pore volume of mortars. Also, the samples made with up to 15% RHP and 7% EP improved the resistivity by up to 80% and 15%, respectively, providing better resistance to chloride ion migration. Based on the results, it is recommended to use the RHP and EP up to a level of 5% and 7%, respectively, in sustainable M30 grade mortar production.

Effect of rice husk morphology on the ability to synthesize silicon carbide by pyrolysis method

Silicon carbide (SiC) is a mineral with good technical properties and high economic value. However, the synthesis of SiC is expensive because it is synthesized at a high-temperature environment (above 1500oC). The synthesis of SiC from biomass can significantly reduce the synthesis temperature. One commonly used biomass material for synthesizing SiC is rice husk. However, the ability to synthesize SiC depends on the shape of the rice husk. The influence of the morphology of rice husk on the ability to synthesize SiC was studied in this study. Experimental results showed that the original rice husk would give better SiC formation capacity than the rice husk powder. The amount of SiC formed using the original rice husk when impregnated by sodium silicate solution and pyrolysis at 1200oC is 18.3% (wt%.). With rice husk powder, it is 15.12% (wt%.). The results of analysis of the mineral composition, functional groups, and morphologies by X-ray diffraction (XRD), Fourier Infrared Transform Method (FT-IR), and Scanning Electron Microscopy (SEM) found that the polymorphy of SiC is α-SiC and β-SiC. These minerals are the basis for SiC from rice husks, which can be applied as wear-resistant materials.

Multi‐objective optimization of hybrid polypropylene composites for enhanced mechanical, thermal, and flame‐retardant properties

AbstractOptimizing composite materials is crucial for engineering advancements because it allows for the creation of materials tailored to specific functional requirements, thereby enhancing efficiency, safety, and sustainability. This study examines both the combined and individual effects of long flax fiber (LFF) bundles, short basalt fibers (BF), and rice husk powder (RHP) on the properties of polypropylene (PP) hybrid composites. LFF primarily provides mechanical strength, BF enhances mechanical, thermal, and flame‐retardant properties by filling gaps, and RHP reinforces and improves the overall composite. Contrary to previous studies that relied on random combinations, this research employs a systematic Box–Behnken design (BBD) for three variables: LFF plies, BF, and RHP by weight percentage. This approach facilitated the development of a new second‐order regression equation via response surface methodology (RSM), clarifying the contribution of each component, with R2 values exceeding 0.85, indicating high predictability. Optimization, conducted using a non‐dominated sorting genetic algorithm (NSGA‐II), demonstrated that the optimal composites significantly outperformed the non‐optimized ones in mechanical strength, thermal stability, and flame retardancy. Compared to the average values before optimization, improvements post‐optimization included increases of 49.86% in tensile strength (TS), 38.82% in TS modulus, 73.93% in char yield (YC), and 29.81% in peak heat release rate (pHRR). Specifically, the fire performance index improved by 237.5% and the fire growth index by 101.33%, compared to pure PP, highlighting significant advancements in fire safety. This study shows that mathematical equations can predict composite properties, helping to select balanced compositions without sacrificing flammability.Highlights Multi‐filler approach technique used for manufacturing of PP composites. LFF, BF & RHP optimize mechanics & flammability. Box–Behnken design predicts optimal composition for superior properties. NSGA‐II optimization improves tensile, thermal & flame retardant properties.

Conversion of rice husks into carbonaceous materials with porous structures via hydrothermal process

Carbonaceous materials hydrothermally produced using waste biomass have small specific surface areas (SSA) and poor porosity properties. In this study, we prepare a novel carbonaceous material with excellent porosity properties by suppressing the formation of a secondary char phase (spheres) and promoting biomass hydrolysis by controlling the hydrothermal conditions. Rice husk powders, as the starting material, are hydrothermally treated using acidic solvents of different types and concentrations at 180 °C. The surfaces of the samples hydrothermally prepared using the acidic solvents have no spheres. In the case of 0.1–0.2 mol L−1 hydrochloric acid (HA), the amorphous carbonaceous materials contain numerous mesopores and exhibit a larger SSA (approximately 100 m2 g−1) than those prepared using acetic acid and distilled water. An increase in the hydrothermal temperature reduces the porosity properties of the materials. Finally, the high-porosity amorphous carbonaceous material showed excellent trimethylamine adsorption ability.

Effective sludge management: Reuse of biowaste and sewer sediments for fired bricks

ABSTRACT This study partially replaced the clay with sewer sludge (SS) and rice husk (RH-SS) to make fired bricks. The brick samples were examed in terms of shrinkage, water absorption, and compressive strength. Besides, they were analyzed via XRD and metal extraction to determine the heavy metal residuals in the products. The results showed that it was possible to fabricate fired bricks using sewer sludge or rice husk-blended sludge with up to 30% by weight. These brick samples complied with the technical standard for clay brick production, in which the compressive strength was more than 7.5 MPa, water absorption was from 11–16%, and the linear shrinkage was all less than 5%. The rice husk addition helped mitigate the heavy metal residuals in the bricks and leaching liquid, in which all the values were lower than the US-EPA maximum concentration of contaminants for toxicity characteristics. Implications: Previous studies have proved the possibility of mixing sewage sludge from different origins (sewage sludge, river sediment, canal sediment, sewer sediment, etc.) with clay and some wastes to make bricks. In which, mostof the studies used sewage sludge from wastewater treatment plants, very fewdealt with lake/river or sewer sediment. This study shall be the first to study the possibility of employing sewer sediments with the addition of rice husk powder to achieve two targets, including (1) the reuse of biowaste and sludge for brick fabrication and (2) the reduction of heavy metals in final calcined bricks. Different ratios of the rice-husk blended sewer sludge (RH-SS) – clay mixture shall be tested to find the optimized compositions. The results showed that it was possible to fabricate fired bricks using sewer sludge or rice husk-blended sludge with up to 30% by weight, which meant reduce 30% of clay in the brick production. The final products were proved to meet the quality standard in terms of compressive strength (more than 10 MPa), water absorption(from 11–16%), and the linear shrinkage (less than 5%). Larger scale of this study can be an evident to recommend for policy change in the waste reuse in construction field.

Effect of cement-based composite pellets on phosphorus removal and microbial community structure in eutrophic water

Phosphorus (P) removal still faces challenges in eutrophic water treatment. Combining adsorption and biological reactions can efficiently reduce the P concentrations, achieving long-term function. In this study, five kinds of pellets were produced using cement, bentonite, and organic carbon (rice husk powder) with mass ratios of 100%:0%:0% (M1), 95%:5%:0% (M2), 92.5%:5%:2.5% (M3), 90%:5%:5% (M4), and 85%:5%:10% (M5) for phosphorus removal in eutrophic water. The static adsorption experiment revealed that both Langmuir and Freundlich models were suitable for describing the adsorption characteristics. The P-bonding energy (KL) and adsorption capacity (K) followed the order of M1 < M2 < M3 < M4 < M5. The adsorption processes conformed to the Pseudo-second-order kinetic model. The adsorption capability of pellets decreased with increasing pH levels. The Cl−, NO3−, and SO42− showed negligible effects on adsorption, while CO32− reduced the adsorption amount. In the dynamic experiment, all the pellets have sustained P removal efficiency with the average removal rates of 58.54% (M1), 60.78% (M2), 63.97% (M3), 66.81% (M4), and 72.05% (M5). The presence of CaHPO4·2 H2O in pellets after P removal indicated phosphate precipitation and ion exchange. The attached microbes in pellets exhibited an increase in Proteobacteria abundance contributed to biological phosphorus removal and long-term effectiveness. Hence, this study introduces innovative cement-based pellets for phosphorus removal in eutrophic water, establishing a possibility for practical applications.

Effects of chitosan and rice husk powder on thermal hydrolysis-anaerobic digested sludge conditioning: Dewaterability and biogas slurry fertility

To enhance the dewaterability of anaerobic digested sludge and to make full use of the biogas slurry. This study set up five sludge conditioning methods: polymeric ferric sulfate, polymeric aluminum chloride, cationic polyacrylamide, chitosan, and chitosan combined with rice husk powder. Their effects on the dewaterability of thermal hydrolysis-anaerobic digested sludge, bacterial community, and biogas slurry fertility were studied to find a non-toxic and non-risk dewatering technology for the environment and biogas slurry. Compared with that of the control group, moisture content, normalization capillary suction time, and specific resistance to filtration were reduced by 12.8%, 97.7%, and 82.9%, respectively. Chitosan enlarges the sludge flocs and forms complexes with proteins, disrupting the structure of the extracellular polymeric substances, thereby exposing more hydrophobic groups and reducing the hydrophilicity of the sludge. The subsequent addition of rice husk powder enhances the adsorption of hydrophilic substances and provides a stronger drainage channel for the sludge. In addition, the biogas slurry obtained by this conditioning method used as a fertilizer increased the dry weight and fresh weight of corn seedlings by 59.3% and 91.0%, respectively. And the total chlorophyll content increased by 84.6%. Pearson's correlation analysis showed that chitosan and rice husk meal had no toxic effect on the biogas slurry compared to the other three flocculants. The results showed that the combined treatment of chitosan and rice husk powder resulted in the best dewaterability. Overall, chitosan combined with rice husk powder is a green dewatering technology with great potential for anaerobic digested sludge dewatering and biogas slurry recycling.

Pyrolysis of rice husk in molten lithium chloride: Biochar structure evolution and CO2 adsorption

Biochars are attained by direct pyrolysis of the mixture of rice husk (RH) powders and lithium chloride within 600–800 °C. The physical and chemical properties of RH biochars are studied using diverse characterization techniques. Effects of pyrolysis temperature and salt/biomass ratio on the structure properties and CO2 adsorption performances of RH biochars are tested at 25 °C and 100 kPa. The results show that the CO2 uptakes of RH biochars first ascend and then descend with incremental pyrolysis temperature and basically increase with the elevation of the salt/biomass ratio. The biochar prepared at 700 °C with the salt/biomass ratio of 7.5 in an air atmosphere presents the highest CO2 uptake of 2.70 mmol/g, which is much higher than the one (1.98 mmol/g) obtained at 700 °C without addition of LiCl salts in a nitrogen stream mainly due to its bigger specific surface area, higher contents of chemisorbed oxygen and carbon defect structures. Pyrolysis of rice husk in molten LiCl can effectively improve the porosity and the surface functionality of the biochar, thereby enhancing its CO2 capture performance.

Rapid assessment of wetting of natural fiber surfaces by biodegradable copolyester using spectroscopic and microscopic techniques

AbstractA biodegradable polymer, the poly(butylene adipate co‐terephthalate) (PBAT), was compounded with the microcrystalline cellulose (MCC) obtained from different sources (such as wheat stalk and rice husk powder) to prepare the polymer composites. The two components, here found to be compatible, as evidenced by the Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). Further assessment of the compounded fibers with the organic solvent, the toluene, illustrated the nature of the wetting phenomena of MCC by PBAT. The SEM observation showed the wrapping of the PBAT layer onto the MCC phase after the removal of the polymer matrix. The FTIR spectrum showed the presence of the PBAT carbonyl peak on extracted fibers from the composite via solvent removal. It could be concluded that the PBAT could wet the MCC effectively in the composites suggesting the potential of enhancing their properties.Highlights A biodegradable polymer, the PBAT, melt‐mixed with plant‐based natural fiber. The fiber in composites was found to be wetted with the PBAT layer. H‐bonding between the CO group of PBAT and the OH group of fiber caused wetting. Raw, processed, and silane‐treated fibers showed similar wetting phenomena.

Effect of hybrid eco‐friendly reinforcement and their size on mechanical and flame retardant properties of polypropylene composites for technical applications

AbstractWhile the potential of natural fiber (NF) composites for various engineering applications is well‐recognized, a deep understanding of the intricate interactions within these composites remains crucial. This study examines the microstructural characteristics of the polymer matrix and evaluates the impact of reinforcement size, with a particular focus on fire sensitivity. Hybrid‐reinforced polypropylene (PP) composites were introduced using a unique tri‐hybrid system. This system combines long flax fibers (LFF) as primary reinforcement, with short basalt fibers (BF) and micro rice husk powder (RHP) as secondary reinforcements. These composites were fabricated using innovative extrusion, compression, and injection molding techniques. This novel fabrication method and strategic hybrid design bridged gaps in the composite structure, leading to significant enhancements in tensile and flexural strength. Improvements of 57.82%, 67.53%, and 60.02% over LFF/PP composites were observed, respectively. On the thermal front, the char residue surged by an impressive 497.51%. Flame properties, notably pHRR and THR, were reduced by 57.25% and 13.28%, respectively. These enhancements are attributed to the lignin in BF and the silica in RHP. The fire safety index further confirmed these improvements, with FGI and FPI increasing by 27.33% and 111.11%, respectively.

The Mechanical Properties of a Water Hyacinth/Rice Husk Powders Composite for Tissue Engineering Applications

In this study, composites made from water hyacinth powder (WPH) and rice husk powder (RH) were created using the hot press method, and the composites were characterized to determine their suitability for biomedical applications such as tissue engineering. The mixing ratio of WPH/RH was investigated. Fourier transmission infrared spectroscopy (FTIR) revealed the presence of chemical bonds in the composites under investigation. Tensile tests were used to investigate the mechanical properties of the composite, which revealed that adding water WPH to the rice husk composite reduced the composite's strength. A composite with a 5% WPH content had the highest tensile strength of 32.72 MPa. Meanwhile, the mechanical strength of the other composites studied ranged from 25,537 MPa to 29.43 MPa. However, the elastic modulus of the composite increased with the addition of WPH. The SEM image shows that the powder distribution is less even, the interface between WPH-RH and polyester is quite tight, and the composite contains a number of voids. Characterization of the developed composite demonstrates that the WPH/RH addition ratio can be adjusted to achieve the desired composite properties for tissue engineering and cartilage regeneration applications.

Morphology, Thermal and Mechanical Property of Thermoplastic Starch Biocomposite

Thermoplastic starch bio-composite compound of cross-linked cassava starch has been produced by a twin screw extruder. Rice husk powder, bacterial cellulose fiber and glycerol were incorporated into the starch at various compositions. Bio-composite compounds were thermally compressed into a mechanical test specimen. Influences of reinforcing materials and plasticizer contents were investigated. An extrusion (160°C) and compression (200°C) at higher temperature produced a greater structural deformation of the cross-linked starch than a processing at lower temperature. Morphology of the bio-composite showed a homogeneous distribution of reinforcement in the matrix at high temperature processing and showed good adhesion between rice husk particle, bacterial cellulose fiber and starch matrix. Flexural and tensile mechanical properties of the bio-composite significantly improve with only 0.71%wt bacterial cellulose incorporation.

Sustainable use of rice husk powder and bamboo powder as sludge deep dewatering conditioners in pilot-scale application: Feasibility for incineration and potential application for land use

Conventional conditioners are not conducive to the sludge separate incineration process. The agricultural wastes bamboo powder (BP) and rice husk powder (RHP) have strong toughness and porosity, which has the potential to replace quicklime as a sludge conditioner. When the dosage of BP and RHP is 30 % of the sludge dry solids, the dewatering performance of sludge was greatly improved after sludge was conditioned with BP and RHP respectively, where the specific resistance of sludge was reduced from 4.6 × 1012 m/kg to 1.3 × 1012 and 0.9 × 1012 m/kg. In addition, the sludge conditioned by BP and RHP acquired better filtrate quality, which is conducive to the stable operation of the wastewater treatment plants (WWTPs). The components of extracellular polymer substances (EPS) showed that the tightly bound-EPS (TB-EPS) decreased by 36.6 % after conditioning with quicklime, while the TB-EPS maintained with BP and RHP conditioning, indicating that the dewatering mechanism of BP and RHP involves physical activities to work as the skeleton builder. The use of BP and RHP increased the enrichment effect of nitrogen and phosphorus in the sludge cake, yet the contents of heavy metals Cd, Pb and Zn were below the sludge land use limit. Combined with the ecological risk assessment by the methods of the Geoaccumulation index (Igeo), the Nemerow pollution index (PI) and the potential ecological risk index (RI), the ecological risk index of quicklime-conditioned sludge is higher when the dewatered sludge is composted and applied for land use, while the ecological risk after conditioning by BP and RHP is in a slightly polluted or non-polluted state, therefore the application of BP and RHP as the deep dewatering conditioners possesses practical potential for land use.

Rice husk coated with copper oxide nanoparticles for 17α-ethinylestradiol removal from an aqueous solution: adsorption mechanisms and kinetics.

The 17 α-ethinylestradiol (EE2) adsorption from aqueous solution was examined using a novel adsorbent made from rice husk powder coated with CuO nanoparticles (CRH). Advanced analyses of FTIR, XRD, SEM, and EDSwere used to identify the classification parameters of a CRH-like surface morphology, configuration, and functional groups. The rice husk was coated with CuO nanoparticles, allowing it to create large surface area materials with significantly improved textural qualities with regard to functional use and adsorption performance, according to a detailed characterization of the synthesized materials. The adsorption process was applied successfully with elimination effectiveness of 100% which can be kept up to 61.3%. The parameters of adsorption were affecting the adsorption process significantly. Thermodynamic data stated that the process of adsorption was endothermic, spontaneous, chemisorption and the molecules of EE2 show affinity with the CRH. It was discovered that the adsorption process controlled by a pseudo-second-order kinetic model demonstrates that the chemisorption process was controlling EE2 removal. The Sips model is regarded as optimal for representing this practice, exhibiting a significantly high determination coefficient of 0.948. This coefficient implies that the adsorption mechanism indicates the occurrence of both heterogeneous and homogeneous adsorption. According to the findings, biomass can serve as a cheap, operative sorbent to remove estrogen from liquified solutions.

Agro Based Material (Rice Husk Powder and Carbon Nanotubes) as Reinforcement in the Development of a New Polymer Bio-composite

Attempts to remedy the problem of cost since most agro wastes are relatively available at low cost, these agro based materials have successfully found significant application in improving the performance of polymeric materials, In this research, a PP with rice husk and carbon nanotubes as composite material with useful application in construction and structural design were been developed. Alkali treatment is significant in enhancing the mechanical properties of the fiber through the removal amorphous portion, increases the crystallinity and strength of the natural fiber reinforced polymer composites, tensile test results shows that the ultimate tensile strength at 5% for rice husk, as shown in the results, a decline in tensile and flexural strength from 5% filled composite were attributed to agglomeration as filler concentration increased. Hence the better the dispersion of the filler in the macromolecular chains of the matrix, the better enhanced the mechanical property will be.