Rice Husk Research Articles

Porous carbon materials derived from rice husk pyrolysis with NaCl/Na2CO3 binary molten salt for CO2 capture

Porous carbon materials derived from rice husk pyrolysis with NaCl/Na2CO3 binary molten salt for CO2 capture

A comparative study on stabilization efficiency of kaolinite and montmorillonite clays with fly ash (FA) and rice husk ash (RHA)-based geopolymers

A comparative study on stabilization efficiency of kaolinite and montmorillonite clays with fly ash (FA) and rice husk ash (RHA)-based geopolymers

Fracture and Mechanical Properties of GGBFS-Based Geopolymer Concrete Incorporating Rice Husk Ash and Natural Zeolite

Fracture and Mechanical Properties of GGBFS-Based Geopolymer Concrete Incorporating Rice Husk Ash and Natural Zeolite

Enhancing long-term alkaline durability of epoxy-coated flax textile for internal concrete reinforcement: Surface modification & matrix integration with rice husk ash

Enhancing long-term alkaline durability of epoxy-coated flax textile for internal concrete reinforcement: Surface modification & matrix integration with rice husk ash

Stabilization of Soft Soil with Rice Husk Ash on CBR Bearing Capacity and Soil Shear Strength Parameters

Bekasi Regency generally has an area with soft clay soil conditions, recognized as problematic soil known as expansive clay. As large-scale construction continues in the region, geotechnical issues associated with these expansive soils have become a concern. Stabilizing with additives increased the soil’s bearing capacity and shear strength. The addition of agricultural waste material, rice husk ash (RHA), is intended to improve the soil through a pozzolanic reaction. This study examines soft soil's bearing capacity and shear strength value with 5%, 10%, and 15% rice husk ash. Index properties tests comprising water content, specific gravity, grain size analysis, and Atterberg limits. Engineering properties tests comprising proctor compaction, California Bearing Ratio (CBR), and UU Triaxial. The samples cured for two days before compaction and seven days after compaction. The test results indicated that the soil was classified as CH according to USCS and A-7-6 according to AASHTO. The highest CBR and Triaxial UU test results were found with an RHA content of 15%. CBR increased by 86.44% from 4.919% to 9.172%. Cohesion value increased by 90.31% from 0.185 kg/cm2 to 0.352 kg/cm2. This study indicates that RHA could increase bearing capacity and shear strength in soil stabilization.

Synergistic passivation of black phosphorene with both silver nanoparticles and rice husk biochar for enhanced electrochemical detection of baicalin

Synergistic passivation of black phosphorene with both silver nanoparticles and rice husk biochar for enhanced electrochemical detection of baicalin

Utilizing Rice Husk Ash as Cement Replacement in Pervious Concrete: A Review

Utilizing Rice Husk Ash as Cement Replacement in Pervious Concrete: A Review

Flexural behavior of reinforced high strength concrete slabs containing glass powder, flay ash, and rice husk ash as cement substitute

Flexural behavior of reinforced high strength concrete slabs containing glass powder, flay ash, and rice husk ash as cement substitute

A Comprehensive Study on the Physicochemical Characterisation of Plant-Based By-Products.

The rapid growth of the global population has led to significant environmental impacts, driven by the unsustainable extraction of resources and waste generation. To address these challenges, the valorisation of by-products from different industries is crucial for maximising resource efficiency, reducing waste, and promoting sustainable practices. In this study, a comprehensive characterisation of the physicochemical properties of plant-based by-products, including rice husk (RH), oregano stalks (OS), eucalyptus leaves (EL), and almond shells (AS), was conducted. The analyses of the residues showed that, despite the similarities regarding cellulose and lignin content in all materials, RH and OS present a higher cellulose content, while EL and AS contain a greater percentage of oils. Additionally, calcium and potassium were identified as the metals at higher concentrations in all residues. The EL and RH present significant hydrophobic properties compared to the other analysed residues, showcased by their lower wettability. The morphological analyses of the waste residues revealed that OS and RH particles exhibit fibrous characteristics with heterogeneous sizes, while EL is a blend of fibrous and amorphous particles, and AS is composed of smaller particles with irregular shapes. All the residues retained their antioxidant properties over a 12-month storage period, with no degradation due to grinding. The composition and physicochemical properties of these residues highlight their potential to be used in distinct industries, including construction, transport, and textiles, promoting a circular economy and supporting a more sustainable environment.

Abundance of fungi on rice straw compost and husk biochars by in-vitro heavy metals mycosorbent

Abstract. Palupi NP, Kesumaningwati R, Sripati AB, Hardi EH, Fahrunsyah, Rahayu DE, Nugroho RA, Darma S, Idris SD. 2025. Abundance of fungi on rice straw compost and husk biochars by in-vitro heavy metals mycosorbent. Biodiversitas 26: 1983-1990. In Samarinda, all paddy fields are contaminated by heavy metals with concentrations exceeding the critical threshold and has disrupted human health and worsened the quality of the agroecosystem of rice fields. This study aims to evaluate the effectiveness of compost and biochar application in absorbing heavy metals in paddy field soil in Samarinda. The research method involves the application of compost, biochar, and their combination on paddy field soil contaminated with heavy metals using incubation experiment with 5 treatments and 4 replications, completely randomized design, and measured parameters (pH, Fe, Zn Cd, and Aspergillus niger). The results indicate that the use of compost significantly increases the population of A. niger and reduces the concentration of heavy metals such as Fe, Zn, and Cd in the soil. On the other hand, biochar has also proven effective in reducing the content of heavy metals, supported by its high adsorption capacity. The combination of compost and biochar shows better results compared to individual applications, indicating synergy between organic nutrients and adsorption capabilities. The correlation between the population of A. niger and heavy metals demonstrates a significant relationship, confirming the role of microbes in soil bioremediation. The practical implication of this research underscores the importance of organic fertilizer use in reducing heavy metal contamination, supporting sustainable agriculture, and reducing dependence on synthetic chemicals. Future research is recommended to further understand the mechanisms of bioremediation and soil microbe interactions in this context. In conclusion, the application of compost and biochar offers a holistic approach to effectively address heavy metal contamination issues, enhance soil quality, and support environmentally friendly agriculture.

Catalytic Performance of Cu-Ni supported on Rice Husk Ash-derived SiO2 for the Hydrogenation of Ethylene Carbonate to Ethylene Glycol

Ethylene glycol, a crucial compound extensively utilized in solvents, coolants, antifreeze, polyester fiber production, and as a natural gas-drying agent, can be synthesized via the hydrogenation of ethylene carbonate. In this study, the synthesis, characterization, and catalytic performance of Cu-Ni/SiO2 catalysts for this reaction, utilizing silica (SiO2) derived from rice husk ash, were investigated. Silica was impregnated with copper (Cu) and nickel (Ni) by varying the weight ratio (Cu:Ni = 10, 7:3, 3:7, 10) to prepare bimetallic catalysts. X-ray Diffraction (XRD) analysis confirmed the presence of both Cu and Ni phases in all the catalysts. The 3Cu7Ni/SiO2 catalyst displayed the lowest reduction temperature and the largest surface area (257.97 m²/g). The 7Cu3Ni/SiO2 catalyst exhibited the highest acidity (1.91 mmol/g) and superior metal dispersion, as confirmed by the Field Emission Scanning Electron Microscopy - Energy Dispersive X-Ray (FE-SEM-EDX) analysis. Catalytic activity was evaluated in a batch reactor under 40 bar H2 pressure at 150 °C for 3 h with a catalyst-to-ethylene carbonate ratio of 5:1. Among the catalysts examined, the 7Cu-3Ni/SiO2 composition demonstrated the highest catalytic performance, achieving 15.14% conversion of ethylene carbonate and 80.51% selectivity towards ethylene glycol. Copyright © 2025 by Authors, Published by BCREC Publishing Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Sustainable Soil Improvement: Soft Clay Stabilization Using Rice Husk Hush and Waste Spent Catalyst RCC 15

This study explores the chemical stabilization of soft clay soil to enhance its bearing capacity and improve its performance under structural loads. A fixed proportion of Rice Husk Ash (RHA) at 6% by weight was combined with varying amounts of spent catalyst RCC 15 (5%, 7%, 9%, and 11%) as stabilizing agents. The experimental program included the characterization of soil index properties, followed by engineering tests with emphasis on Unconfined Compressive Strength (UCS), Atterberg limits, compaction characteristics, and California Bearing Ratio (CBR). The Atterberg limit tests indicated a consistent reduction in the plasticity index (PI) with increasing RCC content, reflecting improved soil stability. Compaction results showed an increase in Maximum Dry Density (MDD) and a decrease in Optimum Moisture Content (OMC), with the highest MDD (13.29 kN/m³) and an OMC of 25.67% achieved at 6% RHA and 11% RCC. UCS values increased progressively, reaching a maximum of 1.822 kg/cm² with the same mixture. CBR results further supported these findings, with unsoaked values increasing from 4.75% to 6.60%, and soaked values from 3.30% to 6.20%. The combined use of RHA and RCC 15 significantly improves the geotechnical properties of soft clay, highlighting its potential as a sustainable and effective construction material.

Field Evaluation of Rice Husk Biochar and Pine Tree Woodchips for Removal of Tire Wear Particles from Urban Stormwater Runoff in Oxford, Mississippi (USA)

Tire wear particles (TWPs), a form of microplastics (MPs) pollution, are transported into waterbodies through stormwater runoff, leading to environmental pollution and impacts on associated biota. Here, we investigated the effectiveness of stormwater filter socks filled with rice husk biochar or pine tree woodchips in reducing TWP pollution in urban runoff in Oxford, Mississippi. Triplicate runoff samples were collected upstream and downstream of the biofilters at two sites during two storm events at peak flow within minutes of the start of the storm and after 30 min. Samples were analyzed for TWPs using a combination of stereomicroscopy, micro-attenuated total reflectance Fourier transform infrared spectroscopy (µ-ATR-FTIR), and scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX). Concentrations (TWPs/L) upstream of the biofilter were variable but highest at the start of the runoff, dropping from an average of 2811 ± 1700 to 476 ± 63 after 30 min at site 1 and from 2702 ± 353 to 2356 ± 884 at site 2. Biochar was more effective than woodchips (p < 0.05) at removing TWPs, reducing concentrations by an average of 97.6% (first use) and 85.3% (second use) compared to 66.2% and 54.2% for woodchips, respectively. Biochar was particularly effective at removing smaller TWPs (<100 µm). Both materials became less effective with use, suggesting fewer available trapping sites and the need for removal and replacement of the material with time. Overall, this study suggests that biochar and woodchips, alone or in combination, deserve further scrutiny as a potential cost-effective and sustainable method to mitigate the transfer of TWPs to aquatic ecosystems and associated biota.

Fabrication and Testing of Epoxy Resin-Based Composites for Electrical Insulation Material Applications

Electrical insulation materials are a critical component in the design and development of electrical systems, playing a crucial role in ensuring the safe and efficient transmission and distribution of electrical power. The aim of this study is to examine the effect of incorporating rice husk ash and silane on the hydrophobicity, leakage current, and tensile strength properties of composite specimens. This study focused on fabricating composites by varying filler concentrations, using epoxy resin as the matrix. The specimens RTV 10, RTV 20, RTV 30, RTV 40, and RTV 50 utilized a filler composed of rice husk ash and silane, with concentrations of 10%, 20%, 30%, 40%, and 50%, respectively. The obtained samples were subjected to testing for leakage current, tensile strength, and water contact angle (hydrophobicity). The study results indicate that increasing the filler content to 40 wt.% in RTV 40 specimens improves the composite’s tracking time, and hydrophobic properties. RTV 40 specimens demonstrated the longest tracking time and the most favourable hydrophobic characteristics compared to the other specimens. However, when the filler content exceeds 40 wt.%, the water contact angle decreases, leading to higher leakage currents and diminished insulating effectiveness. For the RTV 40 specimen, the measured values were a water contact angle of 92°, a tracking time of 1956 seconds, and a tensile strength of 39.59 N/mm². This study addresses several points of the Sustainable Development Goals (SDGs) by improving material properties (SDG 9), promoting sustainable materials (SDG 12) and improving energy-efficient infrastructure (SDG 7).

Glucose Derivative Functionalized Rice Husk Biochar for the Removal of Emerging Contaminant through Adsorption

Glucose Derivative Functionalized Rice Husk Biochar for the Removal of Emerging Contaminant through Adsorption

Research Review on Mechanical Properties of Hybrid Aluminium Metal Matrix Composites Produced through Stir Casting Route

The primary objective of the present investigation is to examine the mechanical characteristics of hybrid metal matrix composites with an Aluminium base, which are made via the stir casting method. The aim of this this review article is to explore the knowledge on the effects of integrating hybrid reinforcements such as Al2O3, SiC, B4C, TiB2, graphite, fly ash etc on mechanical properties of the hybrid aluminium metal matrix produced through stir casting route. Based on various literature survey, the stir casting processing method has demonstrated its capability to create hybrid AMMC with consistent characteristics. Ceramic particle addition to AMMCs is essential to reach the required strength, hardness, and toughness for these materials. Moreover, within the realm of literature, it is stressed that using industrial and agricultural wastes, such as fly ash, coconut shell ash, and rice husk ash, can promote the sustainable practices without sacrificing its mechanical qualities. The usage of light materials has been shown to decrease the overall stiffness of some composites. Emerging research indicates a likely shift toward aluminum-based hybrid composites as a replacement for ceramic-reinforced composites. This transition is driven by several factors, including their cost-effectiveness, abundant availability, and support for sustainable manufacturing processes. These advantages allow for the creation of hybrid AMMC with mechanical properties comparable to those of conventional particulate-reinforced metal matrix composites.

Evaluation of Substrate Effects on the Acclimatization of Two Endangered Curcuma Species

Propagation is necessary for the conservation of threatened species. Curcuma aruna Maknoi & Saensouk and C. pitukii Maknoi, Saensouk, Rakarcha & Thammar. have been successfully propagated using tissue culture methods but two main obstacles to transplantation from in vitro to ex vitro are its low survival rate and its poor adaptability to the ex vitro environment. Therefore, this study examined the effects of different substrate composites on the acclimatization of C. aruna and C. pitukii plantlets from greenhouse conditions. The three treatments of sand, peat moss, and sand, black rice husk, and coconut coir (1:1:1 w/w) were used for acclimatization. Acclimatization of C. aruna and C. pitukii was successful when transplanted into peat moss with a 100% survival rate and higher shoot and leaf growth in comparison to other substrates. The high rates of growth and survival indicate that our work is contributing to the conservation of both Curcuma species and can be used as a model for the transplanting of other Curcuma species.

Comparative Performance of Selected Soil Inoculant, Soil Amendment, and Foliar Fertilizer in Enhancing Upland Rice Production

The rising cost of farm inputs (fertilizers) results in higher production expenses in rice farming; thus, meeting the country’s growing demand for food is at stake due to a lack of capital for production. The agriculture department pinned several strategies to boost rice production through new varieties and mechanization to secure food sufficiency. Contributing to boosting rice production was why this study was encapsulated, and evaluating the efficacy of selected soil inoculants, soil conditioners, and organic foliar fertilizers on agronomic yield and yield components of rice (NSIC Rc 27) was the objective. A completely randomized block design was used in the study (RCBD) with eight (8) treatments: T1 = Farmers Practice (FP), T2 = Recommended Rate of Fertilizers (RRF) Application, T3 = Soil Inoculant Application (SIA), T4 =Foliar Fertilizer Application (Carrageenan) (FFA), T5 = Soil Amendments Application (SAA) combined with soil Inoculants (CRH and Bacillus amyloliquefaciens), T6 = Foliar Fertilizer combined with soil inoculant, T7 = 50% RRF combines with Foliar Fertilizer and soil inoculant and T8 = 50% RRF combines with soil inoculant and replicated thrice in a 4m x 5m standard size with a total area of 646m2 with the duration of two years. The research was conducted at Davao de Oro State College’s research laboratory at Compostela, Davao de Oro. Agronomic parameters, meteorological data, yield and yield components, and economic analysis were collected. The results confirmed that various approaches increased upland rice production by up to 3.9 tons per hectare. On the other hand, soil conditioners and soil inoculants like carbonized rice hull (CRH) and Bacillus spp could improve soil health by increasing organic matter, resulting in better absorption of nutrients correlating to higher production.

Optimizing Artificial Soil Mixes for Urban Green Spaces: Plant Growth and Carbon Sequestration Balance

Background and objective: As urbanization accelerates, urban areas are significantly contributing to greenhouse gas emissions worldwide. Artificial green spaces, such as green roofs, have emerged as vital strategies for mitigating urban carbon emissions while providing essential ecosystem services. However, the existing research in this area predominantly addresses the carbon sequestration potential of vegetation, leaving the role of soil materials in artificial ground systems underexplored. This study aimed to identify optimal material compositions and blending ratios for Artificial Soil Mixes (ASMs) that enhance carbon reduction while satisfying essential plant growth requirements.Methods: Eight soil materials frequently used in artificial greening —bottom ash, biochar, zeolite, peat-moss, carbonized rice hull, humus, vermiculite, and cocopeat—were blended into four distinct ASMs (ASM_A, ASM_B, ASM_C, and ASM_D). Each ASM was assessed based on its (1) physicochemical properties, (2) elemental composition, and (3) plant growth performance.Results: ASM_A exhibited comparable or slightly superior growth to the control soil, likely due to its high organic matter content and cation exchange capacity (CEC). ASM_D demonstrated the highest carbon content (27.60 wt%) among the blends, highlighting its significant potential for long-term carbon sequestration. However, its lower nitrogen and phosphate contents limited its effectiveness during early plant growth stages.Conclusion: This study contributes by developing lightweight artificial soil mixes that simultaneously support basic plant growth and enhance carbon reduction. For improved germination and initial plant growth, ASMs with higher available phosphorus and organic matter contents are recommended. Conversely, ASM_D, which is rich in recalcitrant carbon, presents greater advantages for long-term carbon mitigation. These findings underscore the necessity of further research to refine soil blends that optimally balance plant growth and carbon sequestration potential in artificial green spaces such as rooftop gardens.

Functionalization of Rice Husk for High Selective Extraction of Germanium

It is of strategic significance to extract germanium (Ge) in an ecological way for sustainable development. Adsorbents that already adsorb Ge have disadvantages such as poor selectivity and low adsorption capacity. In this study, a novel adsorbent material based on rice husk functionalized with tannic acid was developed for the efficient extraction of Ge from simulated coal fly ash leachate. The adsorption capacity of tannic acid-functionalized rice husk (TA-EPI-ORH) for Ge was 19.9 times higher than that of untreated rice husk, demonstrating significantly improved performance. The results showed that the adsorption process of Ge by TA-EPI-ORH is consistent with pseudo-second-order kinetic and Freundlich isotherm model. TA-EPI-ORH had excellent selective adsorption properties, with adsorption of 1.40 mg L−1 Ge exceeding 95% and solid-liquid partition coefficients of 4380 mL g−1, even in the presence of nine impurity metal ions (average concentration: 479.08 mg L−1). When compared with the two main coexistence ions—aluminum (Al) and calcium (Ca)—both of which have the relatively highest concentrations (Al: 1594.20 mg L−1, Ca: 1740.13 mg L−1), the separation factors for Ge still maintain relatively high level with SF(Ge/Al) = 42.57 and SF(Ge/Ca) = 39.93. Compared to existing studies, TA-EPI-ORH exhibits superior selective adsorption performance even with the presence of more interfering ions. After elution of the adsorbed Ge from TA-EPI-ORH, the extraction rate of Ge with low initial concentration (1.40 mg L−1) reached 85.17%, while the extraction rates of Al and Ca were only 1.02% and 1.18%, respectively. Further research revealed that the catechol groups on the surface of TA-EPI-ORH formed stable complexes with Ge, whereas the complexes with coexisting ions (e.g., Ca and Al) were unstable, thereby ensuring high selectivity for Ge. This green chemistry-based functionalization of rice husk not only enables high-value utilization of agricultural waste but also provides a sustainable and eco-friendly strategy for efficient Ge separation and recovery.