Rice Husk Ash Research Articles

Environmental Management Practices and Sustainable Green Concrete Use in Malaysia's Construction Industry: Challenges, Benefits, and Future Directions

This review examines the environmental management practices (EMPs) employed within Malaysia's construction sector, with a particular focus on sustainable practices and the adoption of green concrete, including fly ash, rice husk ash, and palm oil fuel ash varieties. The study identifies key challenges, such as low awareness, high costs, weak legal enforcement, and the underdevelopment of green materials in the country. To address these issues, the report proposes solutions such as capacity-building programs, government incentives like tax breaks and grants, regular site inspections, and investment in research and development of green materials. The review also assesses the advantages and limitations of different green concrete types used in Malaysia. The aim of this study is to enhance sustainability efforts and reduce the environmental impact of construction activities through greater awareness, stronger regulatory support, and commitment from all stakeholders. Implementing greener concrete and EMPs is expected to not only mitigate environmental concerns but also yield long-term economic benefits for Malaysia.

Enhanced mechanical and self-healing properties of rice husk ash-incinerated sugarcane press mud biogeopolymer pastes.

This study examines the use of rice husk ash (RHA) and incinerated sugarcane press mud (ISPM) as precursors in the lime/pozzolan geopolymer system and the effect of the bacterium Lysinibacillus sp. WH on the mechanical properties and microstructures. The RHA-to-ISPM ratio was varied, and the geopolymer pastes were cured at ambient temperature. The results show that an increase of ISPM content up to 5% improves strength and reduces water absorption and voids, while higher ISPM levels beyond 5% degrade the quality of geopolymer paste. An increase in ISPM content reduces setting times due to an increase amount of calcium in the pastes. Notably, the addition of bacteria resulting in a reduction of setting times has been proved for the first time in this work. Moreover, the addition of bacteria can enhance all mechanical properties and introduce self-healing abilities, with microcracks healing within < 20 days of treatment, regardless of mix proportions. Microstructural studies, using a scanning electron microscope (SEM), Fourier Transform Infrared Microscopy (FT-IR), X-ray diffraction (XRD), and Rietveld refinement analysis, reveal that bacteria increase cristobalite, and decrease quartz, thus resulting in strength enhancement of geopolymer pastes. Furthermore, this work is the first to provide evidence that bacteria tend to reduce the efflorescence formation as confirmed by a decrease in gaylussite. These findings pave ways to the production of more sustainable geopolymer systems via upcycling wastes and prolonging service life due to bacterial activity.

The Role and Mechanism of Rice Husk Ash Particle Characteristics in Cement Hydration Process

The Role and Mechanism of Rice Husk Ash Particle Characteristics in Cement Hydration Process

PLASTIC BLOCK FOR BUILDING CONSTRUCTION MATERIAL

Plastic wrap waste increase from time to time. Efforts are needed to utilize them as they are less demanded for recycling by the private sectors in Bali and Indonesia. This paper describe effort to use combination of waste thin plastic wrap as plastic block for wall construction material. The plastic wrap wastes were cut into 5-10 mm size, then they were melted in a hot waste engine oil at 200°C. The mixture was then poured into a metal mold, slightly cooled down and compressed using a compression machine. The mixtures produced was without and with added rice husk ash as filling material. The size of the plastic block was 20×10×8cm. It was found that the densities of the samples were less than 1gram/cm3, the compressive strength can achieve 25kg/cm2, the Porosities were low, ranges from 0.220-0.290%, the Initial Rate of Suctions (IRS) were very low ranges form 0.0004-0.00075 kg/m2.minute, and the and water absorptions were also low (0.02-0.03) %. In general, the compressive strengths were comparable to low quality bricks commonly produced.

Stabilization Of Clay Soil With Rice Husk Ash And Cement

Stabilization Of Clay Soil With Rice Husk Ash And Cement

A sustainable approach to enhance biodegradability of recycled LDPE with starch biofillers derived from potato peels and rice husk ash*

ABSTRACT This study investigates the potential of using starch derived from potato peels and rice husks as biofiller for the production of biodegradable plastics. Starch was extracted from potato peels and modified using phthalic anhydride, formamide and potassium acetate to ensure its homogeneous dispersion into the low-density polyethylene (LDPE) matrix. The modified potato peel starch and rice husk ash were characterised using various techniques such as SEM, TEM, FTIR, XRD and were blended with recycled LDPE to enhance its biodegradability for making it an applicable environmental friendly packaging material. The quantity of the biofiller was varied from 4 to 12 g while rice husk ash content was kept constant (0.6 g). The addition of the biofiller reduced the tensile strength, tear strength and transparency of the film with an increase in haze %, weight loss both in garden soil and vegetable waste environment indicating the enhancement in biodegradability of the produced blend. Considering the applicability constrain biodegradable blend containing 20% starch was considered as the best one having tensile strength of approximately 10.42 MPa, tear strength 69.4 N, weight loss percentage of 13.29% in garden soil and 11.34% in vegetable waste when studied for a period of 360 days. Modification of starch has however increased both the mechanical (tensile strength – 12.628 MPa, tear strength – 80.47 N) and biodegradability (weight loss percentage of 15.19% in garden soil and 14.45% in vegetable waste) of the films when studied under the same conditions for the sample containing 30% starch in the matrix.

OBTAINING OF GARNET CERAMIC MATERIALS BY UTILIZATION OF RICE HUSK ASH AS SILICA SOURCE

The current research aims at the obtaining of new type pigments from the garnet mineral group by utilizationof rice husk ash as silica source (RHA). At the beginning, the mixtures prepared from the starting raw materials areground in a ball mill and then subjected to high temperature treatment. Green pigments were synthesized at twotemperatures: 1000°C and 1100°C. Using the tintometer RT 100 Lovibond the colour characteristics were measuredspectrophotometrically. The rice husk ash was investigated using scanning electron microscopy. The conducted hot-stage microscopic studies show that the pigments remain thermally stable when heated. The highest fire resistance - upto temperatures of 1380°C - 1400°C show the uvarovite pigments with main phase 3CaO.Cr2O3.3SiO2 or by a generalformula Ca3Cr2[SiO4 ]3. They are suitable for inserting into ceramic glazes without danger of decomposition or reaction.Keywords: ceramic pigments, SEM, colour determination, Hot-stage microscopy.

Rice husk ash and recycled sand as synergistic substitutes in ultra-high performance concrete: Microstructural, mechanical performance, and eco-economic analysis

Quartz sand and silica fume (SF), commonly used in UHPC production, are costly and contribute to dust pollution and significant carbon emissions. In this work, we explored the preparation of an environmentally friendly ultra-high performance concrete (e-UHPC) by substituting SF and quartz sand with rice husk ash (RHA) in ratios of 10 %, 20 %, and 30 %, and recycled building sand (RS) in ratios of 25 %, 50 %, and 75 %. We assessed the impact of these substitutions on workability, mechanical strength, hydration products, and the micromechanical characteristics of the interfacial transition zone. In addition, an environmental and economic assessment index for e-UHPC was introduced. Results showed that while RHA and RS reduced the flowability of e-UHPC, RHA helped mitigate the compressive strength loss due to RS (3.9 %-9.7 %). RHA accelerated early hydration, and improved densification in the transition zone, enhancing late hydration and refining the pore structure of e-UHPC. Notably, a 10 % RHA replacement rate optimally improved early hydration efficiency and minimized CH content. The combination of 10 % RHA and 25 % RS proved most effective in optimizing the interfacial transition zone and improving the pore structure of e-UHPC. Importantly, e-UHPC reduces the carbon footprint at a lower cost and offers significant environmental and economic advantages over traditional UHPC. The results of this study will promote the incorporation of construction and agricultural wastes into concrete.

A novel red emitting Eu3+ doped CaSiO3 nanophosphor derived from agro-wastes for advanced forensic applications

The modified sol–gel approach was utilised to synthesise Eu3+ (1–5 mol%) doped CaSiO3 nanophosphors (NPs) using eggshell (ES) and rice husk ash (RHA) as precursors for SiO2 and CaO, respectively. Powder X-ray diffraction (PXRD) peaks confirm the monoclinic structure of the powdered samples. The photoluminescence (PL) emission spectra display distinct emission peaks corresponding to Eu3+ ions. After optimizing the Eu3+ ion concentration, the highest intensity (CaSiO3:3Eu3+) was achieved at 3 mol%. As the concentration increased beyond this point, the emission intensity decreased due to concentration quenching (CQ). Temperature-dependent photoluminescence (TDPL) was investigated in the range of 303 to 443 K. The results demonstrated that emissions at elevated temperatures are significantly stronger than those at ambient temperature. TDPL studies revealed excellent thermal stability, with emission intensity remaining at 87.5 % even at 423 K. Additionally, the phosphor’s absolute sensitivity of 0.003 K−1 and relative sensitivity of 1.44 % K−1 highlight its strong potential for temperature sensing applications. The suitability of the phosphor for the powder dusting method in fingerprint (FP) detection on various surfaces was also assessed. Under 365 nm UV light, the CaSiO3:3Eu3+ phosphor clearly reveals the level 1–3 structure of LFPs.

Comparison of composition, properties and modifying effect in epoxy compositions of natural and synthetic diopside-containing fillers

Diopside is one of the key components in various construction materials and can also be used as a filler for epoxy compositions. However, due to the complexity and labor intensity of developing domestic deposits of this calcium magnesium silicate, it is rational to synthesize diopside based on rice husk ash and dolomite and compare its phase composition and properties with diopside concentrate mined in nature.It has been established that the synthesized calcium-magnesium silicate, compared to the natural mineral, contains 10 times more diopside, has a 3 times smaller pore volume and an almost 5 times smaller average particle size, i.e. they differ significantly in both phase and granulometric composition, as well as in porosity.At the same time, both natural and synthetic diopside-containing fillers increase the hardness, wear resistance and viability of epoxy compositions. A filler synthesized on the basis of rice husk ash is more effective in terms of increasing the performance characteristics of epoxy materials.

Synthesis of Silica-Based Imprinted Ionic from Rice Husk Ash for Adsorption of Ni(II)

Imprinted ionic synthesis through the sol-gel process for Ni (II) adsorption has been carried out. Sodium silicate from rice husk ash (NaSiO3(RHA)), N1-(3 Trimethoxysilylpropyl) diethylenetriamine (TMPDT) and Ni (II) are stirred, then 6 M HCl is added until a gel forms. Furthermore, 0.1 M EDTA and 0.1 M HNO3 were added to the dry gel to release Ni (II) to form-imprinted ionic material (SiO2-TMPDT-Ni-Imp). The material was characterized using FTIR, SAA, and SEM-EDX. FTIR characterization of SiO2-TMPDT-Ni-Imp indicated the appearance of-OH, -CH, -Si-O-and-NH absorption. The SAA characterization results show a surface area of 18.091 m2/g, a total pore volume of 0.033 cc/g, and an average pore radius of 16.739 Å. The optimum conditions for Ni (II) adsorption by SiO2-TMPDT-Ni-Imp are pH four and a contact time of 100 minutes. The appropriate adsorption kinetic model for the absorption of Ni (II is pseudo-second order with an adsorption capacity of 6.9 mg/g. Keywords: Silica, imprinted ionic, rice husk ash, adsorption, Ni (II)

Transesterification of biodiesel from kapok seed oil (ceiba pentandra) using a natural heterogeneous katalyst (rice husk activation)

Biodiesel as a renewable energy source can be produced by a chemical reaction between vegetable oil or animal fat and short-chain alcohol such as methanol, ethanol or buthanol and is supported by a catalyst. This process is called transesterification. From an environmental point of view, the use of biodiesel has several advantages such as reducing carbon dioxide emissions, being non-toxic and biodegradable. Kapok seed oil has potential for exploitation, particularly as a raw material for the manufacture of biofuel. Kapok seeds (Ceiba pentandra) have the potential to be used as a feedstock for biodiesel because their oil content is quite high, around 18-25% oil. The controlled combustion of rice husks produces ash containing high purity amorphous silica. Amorphous silica can be obtained from RHA (rice husk ash) when rice husk is burned at a temperature of 700°C, and it is transformed into crystalline silica when burned at a temperature above 850 °C. This silica has many applications as a filler, adsorbent, catalyst support, star gel component and source for the production of premium silicon and its compounds. The aim of the research is to determine the transisterification process of biodiesel from kapok (Ceiba pentandra) seed oil. using a natural heterogeneous catalyst in It is an activated rice husk. The method used was the preparation of kapok seed samples and the extraction of sokhlet. Determination of free fatty acids (FFA) in kapok seed oil, activation of rice husk, manufacturing of biodiesel from kapok seed with addition of rice husk H2SO4 as catalyst. The characteristics of the biodiesel produced are Density: 859.88572 kg/m3 (SNI: 7182:2015) = 850-890 kg/m3), Viscosity: 2.45824 cSt (SNI: 7182:2015) = 2.3 – 6, 0 cSt, Calorific value: 7,374.5322 cal/g (SNI: 7182; 2015) = 7,100 -11,000 cal/ g, Devil's number: 48 (ASTM: D6751) = 47. Meanwhile, GC-MS with the highest values at all reaction times, namely Hexadec anoic acid, methyl ester (C17H34O2), methyl tetradecanoate (C15H30O2) and 9 - Octadecenoic acid (Z), methyl ester (C19H36O2) . The functional group found in kapok seeds is –OH.

Physical, Mechanical and Durability Properties of Eco-Friendly Engineered Geopolymer Composites

Engineered geopolymer composite (EGC) is a high-performance material with enhanced mechanical and durability capabilities. Ground granulated blast furnace slag (GGBFS) and silica fume (SF) are common binder materials in producing EGC. However, due to the scarcity and high cost of these materials in some countries, sustainable alternatives are needed. This research focused on producing eco-friendly EGC made of cheaper and more common pozzolanic waste materials that are rich in aluminum and silicon. Rice husk ash (RHA), granite waste powder (GWP), and volcanic pumice powder (VPP) were used as partial substitutions (10–50%) of GGBFS in EGC. The effects of these wastes on workability, unit weight, compressive strength, tensile strength, flexural strength, water absorption, and porosity of EGC were examined. The residual compressive strength of the proposed EGC mixtures at high elevated temperatures (200, 400, and 600 °C) was also evaluated. Additionally, scanning electron microscope (SEM) was employed to analyze the EGC microstructure characteristics. The experimental results demonstrated that replacing GGBFS with RHA and GWP at high replacement ratios decreased EGC workability by up to 23.1% and 30.8%, respectively, while 50% VPP improved EGC workability by up to 38.5%. EGC mixtures made with 30% RHA, 20% GWP, or 10% VPP showed the optimal results in which they exhibited the highest compressive, tensile, and flexural strengths, as well as the highest residual compressive strength when exposed to high elevated temperatures. The water absorption and porosity increased by up to 106.1% and 75.1%, respectively, when using RHA; increased by up to 23.2% and 18.6%, respectively, when using GWP; and decreased by up to 24.7% and 22.6%, respectively, when using VPP in EGC.

Synthesis and application of Fe3O4@RHA nanocatalyst in the synthesis of polyhydroquinolines and dihydropyrimidinones (statistical approach to optimize parameters)

In this study, rice husk ash as silica source was obtained and then, by adding Fe3O4, Fe3O4@RHA core-shell nanocatalyst was prepared. The Fe3O4@RHA nanocatalyst was identified using VSM, XRD, FE-SEM, EDX, and FT-IR analysis, and the optimization of the effective parameters in the reaction was done using response surface methodology (RSM). This nanocatalyst had spherical particles with an average particle size of about 30 nm and good magnetic properties of about 42 emu/gr. The Fe3O4 particles encapsulated in RHA were easily recovered and showed good catalytic activity. Using Fe3O4@RHA biosynthesized nanocatalyst, polyhydroquinoline derivatives were obtained through multi-component condensation of ammonium acetate, aldehyde, ethyl acetoacetate, and dimedone, under solvent-free conditions at 80 °C, as well as dihydropyrimidinone derivatives through multi-component reactions by condensation of urea, aromatic aldehyde, and β-Keto ester under solvent-free conditions at 70 °C. Fe3O4@RHA nanocatalyst was introduced as a heterogeneous, stable, and environmentally compatible catalyst; in its production, dangerous materials, reagents, and solvents were avoided and it is environmentally friendly. In addition, it has the advantage of being recyclable, resulting in short reaction time, high product yield, and economically good performance.

Durability Evaluation of GGBS-RHA-Based Geopolymer Concrete Along with Lightweight Expanded Clay Aggregate Using SEM Images and EDAX Analysis

The durability of geopolymer concrete containing Ground Granulated Blast Furnace Slag (GGBS) and Rice Husk Ash (RHA), along with Lightweight Expanded Clay Aggregate (LECA), was investigated. Six different LWGPC mixtures were made with NaOH molarities of 8, 10, and 12M. For each molarity, two combinations of source materials were selected: 100% GGBS (G) and 80% GGBS with 20% RHA (RG). In all the mixtures, coarse aggregate was substituted with 35% LECA. LWGPC mixtures were exposed to 3% HCl, 5% MgSO4, and 3.5% NaCl for studying the durability properties. The test results demonstrate that 100% GGBS with 12M NaOH (12G) outperformed all other mixtures. The residual compressive strength of 12G mix LWGPC specimens after six months of exposure was found to be 86.4% in an acid environment, 90.6% in a sulfate environment, and 91.4% in a salt environment. The elemental composition analyzed using EDAX reveals that silica, alumina, calcium, and sodium are the predominant elements that form a dense microstructure with N-A-S-H, C-A-S-H, and C-S-H. Further, the inner properties of the specimens exposed to chemicals were examined using MATLAB R2023b and ImageJ 1.54f based on SEM images. The SEM image showed that the porosity of LWGPC specimens ranged from 0.5194 to 0.6748 µm, signifying an enhanced durability performance. The experimental results and microstructural analysis show that the LWGPC incorporating RHA and GGBS with LECA offers a superior performance, making it a promising solution for sustainable and durable construction.

Rice husk ash based complex sodium di silicate – An alternative detergent builder for sodium tripolyphosphate and Zeolite 4A

Detergent builder is an essential part of any detergent powder, as it softens the hard water which hinders the cleaning action of surfactants. Nowadays, sodium tripolyphosphate and Zeolite 4A are used as detergent builders extensively in detergent formulation. Though STPP has higher capacities to remove hardness from the water but has a detrimental impact on the environment like eutrophication and hence it has been banned for detergent application in various countries. Zeolite 4A is currently leading the detergent industry with moderate hardness removal, but it has certain disadvantages like high pH, insolubility, high solid residue in the wash water and needs additives for its activation in the detergent formulation. In this research paper, the better alternative detergent builder known as Complex sodium dislicate (CSDS) is produced using rice husk ash-based sodium silicate. Further CSDS is analyzed using SEM, XRD, and TGA-DSC to explain its physicochemical properties. The calcium exchange capacity evaluation is carried out and is found to be 420 mg eq. CaCO3/gram of CSDS which is higher than STPP and Zeolite 4A. In this study, detergent formulations made with CSDS as a detergent builder were compared with those of STPP and Zeolite 4A to evaluate detergent performances according to the IS 4955:2020 standard.

Synergistic Influence of Vindhyan Sandstone Manufactured Sand and Rice Husk Ash on Concrete Performance

Synergistic Influence of Vindhyan Sandstone Manufactured Sand and Rice Husk Ash on Concrete Performance

Effect of various fibers and rice husk ash on the workability of self-compacting concrete

AbstractThe study aims to investigate and find natural fiber as concrete reinforcement using the self-compacting concrete method. Methods of adding fiber and self-compacting concrete methods are exciting because these two methods have different characteristics and advantages. Therefore, the performance of the fresh-state flow capability of the self-compacting concrete method, which contains various fibers, was observed. Coconut fiber, pineapple leaf fiber, ijuk sugar palm fiber, and artificial polypropylene fiber were used with varying compositions of 0.3, 0.5, and 0.7% by mass of binder. The results show that coconut and pineapple fiber concrete met the European Guidelines for Self-Compacting Concrete standards. The coconut and pineapple fiber concrete performed admirably in all tests.

From cassava peel (Manihot esculenta) to hydrocarbon-rich bio-oil: Catalytic flash pyrolysis as a new valorization route

The valorization of agroindustrial residues for second-generation biofuels has garnered attention due to the increasing demand for low-carbon fuels aligned with transportation sector decarbonization efforts. In this context, cassava processing residues, particularly cassava peel, remain largely unexplored but offer a cheap, abundant, and renewable feedstock that can be converted into hydrocarbon-rich biofuel. Thus, the originality of this study lies in investigating the selective conversion of cassava peel into renewable aromatic hydrocarbons through flash pyrolysis catalyzed by an environmentally friendly MFI-type zeolite synthesized from rice husk ash and diatomite residue. A micro-pyrolyzer interfaced with chromatographic separation and mass spectrometry detection was used to compare the composition of condensable volatile products from catalytic pyrolysis over HZSM-5 with those from catalyst-free pyrolysis. Cassava peel, characterized by high volatile matter content (84.3 %), low ash content (3.19 %), and reasonable energy content (15 MJ kg −1), yielded a high content of valuable platform chemicals, such as carboxylic acids and furans, when subjected to catalyst-free pyrolysis. The catalytic upgrading pyrolysis vapors over the environmentally friendly HZSM-5 catalyst yielded approximately 56.0 % industrially relevant aromatic hydrocarbons and 39.9 % light organic acids. Other strengths of using HZSM-5 in upgrading pyrolysis vapors were its low selectivity for naphthalenes, precursors for coke formation, and the production of hydrocarbons in the gasoline range. Thus, HZSM-5 was an efficient catalyst for promoting deoxygenation and improving hydrocarbon content, with high selectivity for valuable aromatic hydrocarbons. In conclusion, cassava peel showed favorable prospects for conversion into hydrocarbon-rich bio-oil, serving as a valuable precursor for low-carbon biofuels.

Intensification of n-butyl ethanoate synthesis using ultrasound over ammonium sulphate supported on silica extracted from rice husk ash as an efficient heterogeneous catalyst

ABSTRACT The silica extracted from rice husk ash was used as support to load ammonium sulphate ((NH4)2SO4) (10–40 wt.%) and ammonium sulphate supported on rice husk silica ((NH4)2SO4/RHS) catalysts were characterised by Fourier transform infrared (FT-IR), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) and scanning electron microscope (SEM) with EDS techniques. The catalyst was further used to convert butan-1-ol to n-butyl ethanoate in an ultrasonic batch reactor. The study demonstrated the influence of ultrasound and operating parameters on the conversion. The maximum conversion of 88.77% was attained at the optimal operating conditions of temperature 353 K, molar ratio 1:2 (ethanoic acid to butan-1-ol), catalyst loading 4% (w/w), duty cycle 75% and ultrasound power 80 W. When compared with the conventional process, the reaction time was reduced by 54% in ultrasound-assisted synthesis over conventional synthesis. It has been observed that intensification benefits as it lowers reaction time for the ultrasound-assisted approach.