Rice Husk Ash Research Articles

Influence of waste glass and rice husk ash on the dynamic compressive properties and variable-angle shear characteristics of concrete after high-temperature treatment: Experimental and numerical study

This study investigates the use of glass sand, glass powder, and rice husk ash in concrete to mitigate the depletion of natural river sand and cement resources. High-temperature environments were simulated using a muffle furnace, and dynamic compression and variable-angle shear tests were conducted to assess the effects of these recycled materials on the mechanical properties of concrete under normal and high-temperature conditions. Results show that while the dynamic compressive strength of ordinary concrete decreases with increasing temperature, the addition of waste glass and rice husk ash enhances strength and modifies the temperature-strength relationship. Rice husk ash increases the strain rate sensitivity, resulting in higher stress rates and more gradual stress-strain curves. Glass sand concrete exhibited improved energy absorption and resistance to dynamic loads, especially with rice husk ash at elevated temperatures. Additionally, concrete containing glass demonstrated superior cohesion and internal friction angles. An improved plastic damage model was validated through simulations, showing enhanced damage resistance in concrete with rice husk ash at temperatures below 400 °C. This study highlights the potential of waste glass and rice husk ash in improving concrete performance and damage resistance.

Stress-Responsive Gene Expression, Metabolic, Physiological, and Agronomic Responses by Consortium Nano-Silica with Trichoderma against Drought Stress in Bread Wheat

The exploitation of drought is a critical worldwide challenge that influences wheat growth and productivity. This study aimed to investigate a synergistic amendment strategy for drought using the single and combined application of plant growth-promoting microorganisms (PGPM) (Trichoderma harzianum) and biogenic silica nanoparticles (SiO2NPs) from rice husk ash (RHA) on Saudi Arabia’s Spring wheat Summit cultivar (Triticum aestivum L.) for 102 DAS (days after sowing). The significant improvement was due to the application of 600 ppm SiO2NPs and T. harzianum + 600 ppm SiO2NPs, which enhanced the physiological properties of chlorophyll a, carotenoids, total pigments, osmolytes, and antioxidant contents of drought-stressed wheat plants as adaptive strategies. The results suggest that the expression of the studied genes (TaP5CS1, TaZFP34, TaWRKY1, TaMPK3, TaLEA, and the wheat housekeeping gene TaActin) in wheat remarkably enhanced wheat tolerance to drought stress. We discovered that the genes and metabolites involved significantly contributed to defense responses, making them potential targets for assessing drought tolerance levels. The drought tolerance indices of wheat were revealed by the mean productivity (MP), stress sensitivity index (SSI), yield stability index (YSI), and stress tolerance index (STI). We employed four databases, such as BAR, InterPro, phytozome, and the KEGG pathway, to predict and decipher the putative domains in prior gene sequencing. As a result, we discovered that these genes may be involved in a range of important biological functions in specific tissues at different developmental stages, including response to drought stress, proline accumulation, plant growth and development, and defense response. In conclusion, the sole and/or dual T. harzianum application to the wheat cultivar improved drought tolerance strength. These findings could be insightful data for wheat production in Saudi Arabia under various water regimes.

Potential Utilization of Rice Waste in the Construction Sector: A Multi-Criteria Decision Analysis Approach

Effective management of agricultural waste is an important contribution to environmental sustainability and economic development, especially considering the significant volume of agricultural residues produced worldwide. Rice is a widely cultivated crop in Colombia, and its high production results in a high amount of wastes, which is often underutilized due to a lack of knowledge regarding its potential value-added applications. On the other hand, the construction industry has become increasingly aware of the necessity to develop materials with reduced environmental impact. Therefore, this study explores the application of the Analytic Hierarchy Process (AHP) to evaluate various alternatives for utilizing rice waste in construction materials; the alternatives were evaluated based on criteria tailored to the needs of local agricultural communities in the Tolima region of Colombia. The findings highlight the potential of rice husk ash (RHA) as an environmentally responsible alternative in the construction sector, offering a viable solution for waste management while contributing to the economic development of small-scale farmers.

Evaluation of Fresh and Hardened Properties of Concrete made with Rice Husk Ash admixed with Snail Shell Ash

Evaluation of Fresh and Hardened Properties of Concrete made with Rice Husk Ash admixed with Snail Shell Ash

Development of sustainable, high strength slag based alkali activated pavement quality concrete using agro-industrial wastes: properties and life cycle analysis

ABSTRACT Alkali-activated binder-based composites offer a sustainable alternative to cement-based systems, giving a conservational approach. This research incorporated rice-husk ash (RHA) and waste foundry sand (WFS) into ground-granulated-blast-furnace slag (GGBS)-based alkali-activated high-end pavement-quality concretes, optimising with air-curing for expressways, freeways and runway applications. This study promotes sustainable construction by efficiently utilising agro-industrial wastes (i.e., RHA, GGBS and WFS) promoting a global initiative to decrease environmental impact and to adopt eco-friendly pavement construction methods. This study systematically substitutes the primary binder-GGBS with RHA at 5% intervals. The binder was alkali-activated using measured amounts of liquid sodium silicate and sodium hydroxide flakes prepared at an activator modulus (Ms) of 1.25 by maintaining the sodium oxide dosage of 4.0% with respect to the total binder. In particular, 15% RHA (with 85% GGBS) and 20% WFS (with 80% river sand) satisfy mechanical design standards for workability and strength. A comprehensive life cycle analysis using extensive literature support assesses the environmental impact and sustainability of developed pavement quality composites, showing over 70% less energy use than Portland cement-based pavement mixes. Therefore, employing RHA and WFS in air-cured alkali-activated composite manufacture shows that agro-industrial waste components may be used to make sustainable, cost-effective pavement construction. This study effectively advocates for a shift towards environmentally responsible pavement construction, contributing to a greener, more sustainable future in concrete pavement engineering.

Design, modelling and optimisation of ultra high-performance fibre reinforced concrete incorporating waste materials

The adoption of ultra-high-performance fibre-reinforced concrete (UHPFRC) in modern-day construction has gradually increased because of its high compressive and flexural strength at the early production ages. The UHPFRC's high initial cost discourages its production and widespread use. This cost can be reduced by incorporating waste materials in UHPFRC production. This study aims to design, model, and optimise a three-day heat-cured UHPFRC incorporating waste materials. To produce a sustainable UHPFRC mixture, this study combines rice husk ash (RHA) and recycled tire steel fibre (RTSF) as the primary waste components, with Portland limestone cement, river sand, superplasticizer, and water. The concrete is heat-cured in a hot water bath at 90 °C for 3 days, resulting in rapid strength development. A D-optimal mixture design technique was used to optimise the mix proportions, and mathematical models were developed to predict the compressive and flexural strengths. The non-significant lack-of-fit results and the high values of coefficient of determination (R2) revealed the accuracy of the models in predicting the compressive and flexural strengths of the UHPFRC. The low values of standard deviation (SD) and coefficient of variation (CV) confirmed the consistency and reliability of the prediction models. A numerical optimisation revealed that it is possible to design a UHPFRC mixture with a lower cement content of 38.29% of the UHPFRC mix, resulting in a compressive strength of 117.62 MPa and a flexural strength of 36.32 MPa. The study reveals that integrating RHA and RTSF into UHPFRC can yield high-performance properties, offering innovative solutions for resource scarcity and environmental sustainability in the construction sector.

Numerical Modeling of Cathodic Protection for Sustainable Cementitious Materials Incorporating Rice Husk Ash

Numerical Modeling of Cathodic Protection for Sustainable Cementitious Materials Incorporating Rice Husk Ash

Mechanical Characters of Geo-Polymer Concrete for Major Alteration of Cement by Fly Ash

Fly Ash (FA) production exceeded 250 million tons in India by the year 2020 and it would exceeds 450 million tons by the year 2025. This creates huge problems for storage of waste. And it requires hectors of lands to store. It is classified in Class – C and Class – F. Class – C has Pozzolanic properties and self-Cementitious rather to Class – F which attains the same properties by addition of activator. Alkali and Sulfate content in Class – C are higher. Use of Major volume fly ash in addition to lime and admixtures may be permitted to act as Pozzolanic Binder in ordinary concrete to form Geo-Polymer Concrete (GPC). Basically GPC, a Green Concrete (Eco-Friendly Concrete) also made in another way by adding FA, Rice Husk Ash (RHA), Steel Furnace Slag (SFS) and Alkali Activators (AA) following the same process as that of OPC. As the previous studies focuses on strength evaluation of Class – C. The prime objective of this study to examine the comparative characteristics of major alteration of Class – F with Low Calcium GPC subjected to the Tropical Environment with OPC. The findings are observed in the term of Consistencies and it varies from 31 % to 45 % for 0 % alteration of cement to 80 % and lowering and undefined value for 90 % alteration and 100 %. The consistency findings are also observed in progressive range of 32 % to 39 % for addition of Dry Lime from 0 % to 4.5 % (Table - 8) and undefined for 5 % addition. Later on it is observed for 10 % and 15 % addition which shows progressive results. Compression Character (Table - 10) and Flexural Character (Table - 11) is determined for various percentage alteration of PFA and it shows progressive results up to 80 % alteration and percentage difference of 69 % to 85 % for 90 % alteration.

The Influence of Various Biostimulant Formulas Supplemented with Microbes and Their Application Frequency on Corn Productivity in Tidal Swamplands

Corn is the second most important food commodity in Indonesia. However, its production is lower than the demand. This problem can be overcome using suboptimal land, such as tidal swampland, with its naturally low productivity. The soil quality in such areas can be improved by applying biostimulant. Therefore, this study aims to examine various biostimulant formulas supplemented with microbes and their application frequency on corn productivity in tidal swamplands. It was conducted on a pot experiment using a completely randomized block design with three replications. The treatments were six formulas of biostimulant, each with three application frequencies. The biostimulant materials included rice husk ash, golden apple snail extract, and microbes serving as P-solubilizers, N2-fixers, and IAA phytohormone. The results revealed that biostimulant formulas can increase the production of corn. The B3 formula, followed by the B4 and B5 formula, led to superior grain yields compared to the other treatments. In comparison, the most effective application frequency was observed with four times application (D2) followed by five times application (D3) as the next best option. These biostimulant formulas need to be tested in the field to know their effectiveness in tidal swamplands. Keywords: corn productivity, biostimulant formulas, tidal swamplands, microbial supplements

Laboratory assessment of the effect of rice husk, groundnut shells and RHA on the shear, permeability and consolidation of clayey sands

Utilizing waste materials to improve soil properties can result in cost savings and environmental benefits. This study aims to determine the effect of adding agricultural wastes like rice husk ash (RHA), rice husk (RH), and groundnut shells (GS) to clayey sands from Mysore district, India. The study focused on the undrained strength, permeability and volume change behaviour of soils mixed with RHA, RH and GS. The soil samples were mixed with varying amounts of RHA (5%, 10%, 15%, and 20%) and RH-GS (1%, 2%, 3%, 4%, and 5%) and cured for 1, 7, 14 and 21 days. These blended specimens were then used to determine the maximum dry density (MDD), optimum moisture content (OMC) and unconfined compressive strength (UCS). The soil mixture containing 5% RHA and 4% (RH + GS) yielded optimal results in the UCS test. Further tests, including unconsolidated undrained (UU) triaxial, permeability and consolidation tests, were conducted on the parent soil and the soil composite with 5% RHA and 4% (RH + GS). From the undrained test, the strength increased for the soil admixture, with a reduction in the cohesion and an increment in the friction angle, compared to that of the parent soil. The experimental results also showed improvement in the permeability and consolidation characteristics of the blended soil. As RH, GS, and RHA are abundant and considered to be agricultural waste products, using them represents an innovative, sustainable, and cost-effective solution with promising potential for soil improvement.

Influence of water scouring on chloride ion diffusion in rice husk ash recycled aggregates concrete

This study investigates the chloride ion diffusion behavior in concrete incorporating rice husk ash (RHA) and recycled aggregates (RA) under water scouring conditions. The research results indicate that both free and total chloride ion concentrations in recycled aggregate concrete (RAC) exhibit an initial increase, followed by a subsequent decrease, as the distance from the concrete surface increases. The incorporation of RHA reduces both free and total chloride ion concentrations while increasing bound chloride ion content. However, an excessive amount of RHA can weaken the resistance of RAC to chloride ion penetration. Water erosion deteriorates the internal microstructure of RAC, accelerating the transport of free and total chloride ions. However, it does not compromise the chloride ion binding mechanism conferred by RHA. The fine particulate of RHA provides additional nucleation sites for cement hydration, while the reservoir effect ensures a steady supply of free water to these sites. This synergistic interaction enhances the pozzolanic reaction between cement hydration products and RHA, resulting in reduced Ca(OH)₂ content and increased formation of C-S-H gel.

Multifunctional nanoplatforms based on alumina-coated mesoporous silica with potential for cancer theranostics applications

Multifunctional nanoplatforms based on mesoporous silica coated with alumina were successfully and sustainably synthesized using sodium silicate extracted from rice husk ash (RHA), demonstrating the potential for cancer theranostics. The hybrid nanostructures produced (C2-600 and C4-600), from two different calcination times, exhibited distinct morphologies, textural parameters, and degrees of mesoscopic organization. As expected, the Al2O3 coating on the mesoporous silica nanoparticles (MSNs) reduced the specific surface area from 720 m2/g to 122 m2/g (C2-600) and 57 m2/g (C4-600), while preserving their mesoporous structure. Additionally, both C2-600 and C4-600 showed relatively good stability across a wide pH interval, with a zeta potential of ζ = -15 mV and hydrodynamic diameter (Dh) ranging from 160 to 670 nm, depending on the pH of the medium. These peculiar characteristics resulted in high encapsulation efficiency (EE ≈ 90%) for the doxorubicin (DOX) anticancer drug, as well as sustained drug release in simulated gastric fluid (SGF, pH 1.2) and simulated intestinal fluid (SIF, pH 7.4). Appreciably, C4-600-DOX released approximately 83% of the drug over 96 hours and demonstrated significant biodegradation in simulated biological media. Furthermore, the hybrid nanoplatforms exhibited strong optical absorption between 250 and 420 nm, along with broad and intense photoluminescence (PL) in the near-infrared (NIR) region (680-900 nm), which is highly desirable for NIR-fluorescence diagnostic imaging. Notably, the hybrid nanoplatforms without DOX were non-cytotoxic to fibroblast and Caco-2 cells, while the DOX-loaded nanoplatforms exhibited selectivity and potent anticancer activity, inhibiting approximately 80% of Caco-2 colorectal cancer cells after 72 hours. These findings demonstrate that C2-600 and C4-600 are innovative, multifunctional and biodegradable nanoplatforms with powerful potential as drug carriers and fluorescence imaging agents, making them promising candidates for cancer theranostics.

Red luminescence CaSiO3:Eu3+ eco-friendly nontoxic phosphor derived from biomass for display and latent finger print applications

Red luminescent Eu3+ activated CaSiO3 phosphor has been prepared by facile green synthesis hydrothermal route using biomass. Future technologies will be required to synthesize on a massive scale using quick, easy, and affordable ways. The current study deals with the preparation of CaSiO3:Eu3+ using egg shell and rice husk ash. The synthesized powders had a single phased monoclinic structure with space group P1 21/C1. It has been found that addition of Eu3+ ion dopant causes decrease in the optical energy band gap. The phosphor exhibits the intense peak at 612 nm corresponds to 5D0 → 7F2 of the Eu3+ anions upon excitation at 392 nm. The lifetimes ranged from 1.90 to 3.53 ms. With an increase in Eu3+ concentration, emission was tuned towards the red area of the CIE diagram. In order to detect hidden fingerprints on flat surfaces using the powder dusting approach, the CaSiO3:Eu3+ effectiveness was also evaluated. The nontoxicity of CaSiO3:Eu3+ was validated by carrying out a cell viability test on MG 63 cell lines. These outcomes demonstrated that the luminescent CaSiO3:Eu3+ can be used as potential material for display, security encoding, and latent fingerprint applications.

Comparison of Microwave Adsorpsion of Core-Shell Fe3O4@SiO2 by Different Methods

Abstract In this research, magnetite nanoparticles coated with sillica from rice husk ash (core-shell Fe3O4@SiO2) were synthesized by a modified stöber method through hydrolisis of silica using basic catalyst. Phase composition, morphology and microstructure were characterized using XRD, SEM, and TEM. The result shows that the sillica shell was successfully coated the core of nanoparticles magnetite. Core-shell Fe3O4@SiO2were synthesized using two method, first silica extraction and second through the silica gel. The application on microwave absorption are measured using VNA at the X-band frequency (8-12 GHz). Materials reach a reflection loss value of -34,29 dB at a frequency of 10,98 GHz for the first method (extraction of silica). For the second method (through silica gel), it exhibits two maximum absorptions with a reflection loss value under -20 dB, which are -23,05 dB at a frequency of 10,1 GHz and -25,03 dB at a frequency of 10,98 dB.

Sustainable soil stabilization using industrial waste ash: Enhancing expansive clay properties

This study investigates the use of various industrial waste materials—silica fume (SF), cement kiln dust (CKD), calcium carbide residue (CCR), rice husk ash (RHA), and ground granulated blast furnace slag (GGBS)—as eco-friendly stabilizers for expansive clay soil (ECS). Laboratory tests were conducted to assess the impact of different proportions (3 %, 6 %, and 9 %) of these additives on the soil's physical, mechanical, and microstructural properties. Results indicated that the inclusion of industrial waste significantly improved the soil's behavior, with notable reductions in liquid limit (up to 37.66 %), plasticity index (up to 74.76 %), and swell potential. Additionally, unconfined compressive strength (UCS) and shear strength increased substantially, with UCS values rising from 114.64 kPa to 1582.91 kPa at 30 days of curing for 9 % GGBS. Microstructural analyses confirmed the formation of cementitious compounds, which enhanced soil particle bonding and durability. These findings suggest that industrial waste materials can serve as effective and sustainable alternatives to traditional soil stabilizers, offering both performance improvements and environmental benefits.

Salt-freeze resistance and life prediction of geopolymer recycled concrete mixed with rice husk ash and modified rubber particles

Rice husk ash (RHA) and Span-40 modified waste rubber particles (WRP) were mixed into geopolymer recycled concrete (GRC) to improve its frost resistance in normal and chlorine environment. The freeze-thaw and static loading test results show that GRC has the best freeze-resistance when 5 %RHA and 10 %WRP are added. The strength loss rate of GRC after 200 freeze-thaw cycles in normal environment and chlorine salt environment is 8.3 % and 8.8 % lower than that of GRC without RHA and modified WRP, respectively. Based on the test results, the material damage model and strength loss model of GRC doped with RHA and modified WRP were established. The failure probability and service life of GRC were predicted. The results showed that the failure probability of GRC mixed with 5 %RHA and 10 %WRP was reduced by more than 10 % compared with that of GRC mixed with no RHA and modified WRP at 200 freeze-thaw cycles under normal environment and chlorine salt environment, and the failure probability decreased with the increase of cycle times. The life prediction results showed that the service life of GRC mixed with 5 %RHA and 10 %WRP increased by 17.9 % and 21.6 %, respectively, compared with that of GRC mixed with no RHA and modified WRP under the freeze-thaw cycle of normal environment and chlorine salt environment.

Ultrafine GGBS and Fly Ash as Cement Replacement for Sustainable Concrete

The construction industry is one of the major contributors to environmental degradation. Hence, it requires eco-friendly practices to make concrete more sustainable. This can be achieved by addition of mineral admixtures as a cement replacement. This process helps the environment in two ways: by reducing the carbon dioxide emission through cement replacement and by utilizing mineral admixtures such as fly ash, Ground Granulated Blast Furnace Slag (GGBS), metakaolin, rice husk ash and silica fume, which are all industrial wastes or by-products. Hence, this approach lowers the greenhouse effect and global warming by reducing carbon dioxide emissions and prevents environmental contamination by utilizing industrial wastes. This experimental study aims to find the perfect combination of mineral admixtures such as fly ash and ultrafine GGBS to maximize cement replacement in concrete without compromising its mechanical properties and achieving a more sustainable concrete for day-to-day practice. For this study, the fly ash percentage was maintained at 20% for all trials, with the ultrafine GGBS percentage varying from 15% to 30%. Keywords: Sustainable Concrete; Ultrafine GGBS; Fly ash; Mineral Admixture.

CTAB-Si Nanoparticles Derived from Rice Husk Ash for Nitrate Ions Removal in Simulated Wastewater

In this study, silica (Si) nanoparticles derived from rice husk ash is coated with cetyltrimethylammonium bromide (CTAB), a cationic surfactant, and used as adsorbent of nitrate ion in wastewater. CTAB functionalized Si (CTAB-Si) nanoparticles were characterized using scanning electron microscope (SEM), energy dispersive X-Ray (EDX), dynamic light scattering (DLS) Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The synthesized CTAB-Si nanoparticles has a non-spherical shape, with visible polydispersity and is amorphous with average particle size of 72nm. It showed stretching vibrations of silanol at 963cm-1, siloxane at 1073cm-1, sharp peaks at 2852cm-1 and 2922cm-1 due to the methylene tail of CTAB and amine peak at 1,384cm-1. An ∼80% nitrate removal and adsorption capacity of 7.98 mg NO3/g CTAB-Si nanoparticles was obtained at optimized condition using Face Centered Central Composite Design (FC-CCD) at pH 4, 50 mgL-1 of adsorbate concentration, 0.2 gL-1 adsorbent dose and 30 minutes contact time. The adsorption isotherm and kinetic models fits well in Langmuir model and Pseudo second order with a R2 of 0.984 and 0.999 respectively. The efficiency of the nanoparticle after 5 adsorption cycles was ∼50% nitrate removal.

Incorporation of Nanoalumina in Potassium Feldspar-based Phosphoric Acid Activated Geopolymer Composites: A Sustainable Approach

This study investigates the potential of potassium feldspar-phosphate-based geopolymer concrete as a sustainable replacement to traditional concrete, addressing the environmental concerns associated with CO2 emissions during cement production. While geopolymer concrete offers a promising path towards sustainability, its performance often falls short of Portland cement concrete. This study investigates the use of nanoalumina in improving the performance of geopolymer concrete. A ternary mix was formulated with potassium feldspar powder, metakaolin and rice husk ash, incorporating varying percentages of nanoalumina geopolymer concrete mixes. The mechanical characteristics of the resulting geopolymer composites were assessed through compressive and split tensile strength tests. The findings revealed that a 4% nanoalumina dosage (GC-N4) yielded the most significant improvement in strength and durability. The GC-N4 mix performed superior in all metrics, demonstrating the highest compressive (41.82 MPa) and split tensile (3.7 Mpa) strengths. Reduction in water absorption and durability aspects were also optimum in GC-N4. These results highlight the potential of incorporating nanoalumina into a ternary mix of potassium feldspar powder, metakaolin and rice husk ash to significantly enhance the overall performance of geopolymer concrete, promoting its wider adoption as a sustainable construction material.

Experimental Investigation of the Durability of Ambient-Cured Metakaolin-Based Geopolymer Concrete in Different Sustainable Environmental Conditions

Geopolymer concrete (GPC) has received much attention among researchers in recent decades due to its increased durability properties. It helps reduce massive pollution and high energy consumption during cement production. Various cementitious materials having high alumino-silicate, such as, fly ash (FA), ground granulated blast furnace slag (GGBS), rice husk ash (RHA), and metakaolin (MK), are typically used for producing GPC. These materials are activated by an alkaline solution through a polymerization process. This study examined the durability properties of metakaolin-based GPC with fly ash and GGBS under ambient curing conditions (23 ± 20 ℃). The mechanical characteristics like compressive strength, splitting tensile strength, flexural strength, and durability properties like the sorptivity volume of permeable voids exposed to chloride, sulphate, and acid environments were studied and reported. Also, an effort has been made to establish a relationship among the mechanical properties. The test results show that better performance of GPC can be achieved with 40% replacement of MK with 10% FA and 50% GGBS under ambient curing than controlled concrete. The MK-GPC with a higher proportion of metakaolin, showed good resistance to environmental factors. It is a potential alternative to conventional cement concrete.