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1

Characterization of Nanocomposite Mixture Polyvinyl Alcohol and Rice Husk Ash

Sirait Makmur, Sinulingga Karya, Siregar Nurdin

Journal of Ecological Engineering

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2023

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Vol. 24, nr 11

268–-273

EN

Rice husk ash (RHA) nanoparticles were prepared to be applied as a filler in the formation of Polyvinyl Alcohol (PVA) nanocomposites. The manufacture of rice husk ash nanoparticles involved the Ball Mill method and the coprecipitation method, while the manufacture of Polyvinyl Alcohol nanocomposite membranes and rice husk ash was carried out by the sol-gel method. The results of XRD analysis using Match software indicated that the crystal structure of rice husk ash is monoclinic with a particle size of 16.55 nm. The mechanical test results obtained the largest elastic modulus of 29.28 MPa in 3% rice husk ash mixture, the largest tensile test of 8.83 MPa in 1% rice husk ash mixture, and the largest elongation at break of 82.08% in 4% rice husk ash mixture. The addition of rice husk ash as a filler can improve the mechanical properties of PVA/rice husk ash nanocomposites.

2

Study of Zeolite Phase Made from Rice Husk Ash and Sidrap Clay

Armayani M., Mansur Musdalifa, Asra Reza, Irwan Muh, Ramadhanty Dhian, Subaer Subaer, Abdullah Mohd Mustafa Al Bakri, Aziz Ikmal Hakem A., Jeż Bartłomiej, Nabiałek Marcin

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 1

269--274

EN

Zeolite has been successfully synthesized from clay and rice husk ash in the form of powder by using the hydrothermal method with variations in chemical compositions of alkaline solution and the amount of rice husk ash. The clay raw material was obtained from the Sidrap area of South Sulawesi and rice husk ash is obtained from the burning pile of rice husks. Sidrap clay and rice husk ash were activated using an alkaline solution of NaOH and varied rice husk ash and the addition of AlCl3. The addition of AlCl3, an alkaline solution of NaOH and H2O was used in the amount of 25.5 grams and variations of rice husk ash were 2.5 grams and 6.5 grams. Meanwhile, without the addition of AlCl3, an alkaline solution of NaOH and H2O was used for 20.5 grams and variations of rice husk ash from 2.5 grams and 6.5 grams. Then the mixture was then put into an autoclave with a temperature of 100°C for 3 hours. The basic material used in the manufacture of zeolite is carried out by X-ray Fluorescence (XRF) characterization to determine the constituent elements of basic material, which showed the content of SiO2 was 45.80 wt% in the clay and 93.40% in the rice husk ash. The crystalline structure of the zeolite formed was characterized by X-Ray Diffraction (XRD). It was found the resulting zeolite were identified as Zeolite-Y, Hydrosodalite, and ZSM-5. The microstructure properties of the resulting zeolite were determined by using Scanning Electron Microscopy (SEM).

3

Investigation of the reaction mechanism of blended fly ash and rice husk ash alkali-activated binders

Fernando Sarah, Gunasekara Chamila, Law David W., Nasvi M. C. M., Setunge Sujeeva, Dissanayake Ranjith, Ismail M. G. M. U.

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 1

art. no. e24, 2022

EN

This study investigates the influence of the chemical and physical properties of two abundantly available waste by-products in Sri Lanka, fly ash and rice husk ash (RHA) as precursor materials for the synthesis of alkali-activated binders. The suitability of the two types of fly ash and the replacement of fly ash by RHA (10% and 20% by weight of the binder content) were assessed. The study reports the development of compressive strength together with an in-depth analysis of the reaction mechanism of the blended RHA alkali-activated binders. The 100% fly ash mortar achieved the optimum compressive strength of 38.9 MPa at 28 days. Replacement of the fly ash with 10% and 20% RHA reduced the compressive strength by approximately 14% and 43%, respectively. The higher specific surface area of RHA and relatively higher unburnt carbon content in RHA were identified as the major factors influencing the low compressive strength obtained. Furthermore, the addition of RHA increases the reactive silica in the gel matrix and leads to an increase in the Si/Al ratio (3.70–3.89), which has a negative effect on the compressive strength. The difference in solubility rate of precursor fly ash and RHA negatively affect the formation of the gel matrix which is hypothesized as a further reason for the lower compressive strength observed in the RHA mixes.

4

The Effect of Natural Silica from Rice Husk Ash and Nickel as a Catalyst on the Hydrogen Storage Properties of MgH2

Malahayati, Yufita Evi, Ismail Ismail, Mursal Mursal, Idroes Rinaldi, Jalil Zulkarnain

Journal of Ecological Engineering

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2021

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Vol. 22, nr 11

79--85

EN

The characteristics of MgH2 as a hydrogen storage material in this study were observed by varying the composition of the catalyst. The added catalyst was a dual catalyst, namely nickel and natural silica extracted from rice husk ash with a composition of MgH2 + 10 wt% SiO2 + 10 wt% Ni (Sample A), then MgH2 + 5 wt% SiO2 + 10 wt% Ni (Sample B) , and MgH2 + 10 wt% SiO2 + 5 wt% Ni (sample C). The samples were prepared using the high energy ball milling (HEBM). The results showed that the natural silica extracted from rice husk ash (hereafter called “RHA“) can be used as a catalyst in MgH2. Then, simultaneous use of nickel with silica as dual catalyst has shown the improvement in the hydrogen storage characteristics such as temperature and desorption time. The results of this study also indicate that the composition of the catalyst affects the particle size, although the time and milling treatment are the same. Furthermore, the particle size affects the characteristics of MgH2 as a hydrogen storage material. Apart from particle size, there are other parameters that influence the characteristics of MgH2, which appear during the sample preparation process such as impurity and agglomeration phases, all of which are closely related to the composition and type of catalyst used and the milling treatment applied to the sample. The 10 hours milling time used in this study has succeeded in reducing the sample to nano size. The Mg-based materials which have a nanostructure will have a larger contact area for the hydrogen reaction. The diffusion distance during the hydrogen absorption reaction also becomes smaller so as to improve the kinetic and thermodynamic characteristics of MgH2.

5

Partial replacement of cement with rice husk ash in concrete production: an exploratory cost-benefit analysis for low-income communities

Muleya Franco, Muwila Natasha, Tembo Chipozya K, Lungu Alice

Engineering Management in Production and Services

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2021

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Vol. 13, no. 3

127--141

EN

Cement is an important construction material in concrete production; however, it is expensive and unaffordable for many low-income and rural communities in developing countries. Rice husk is a by-product from the rice mill process, with an approximate ratio of 200 kg rice husk per one tonne of rice produced. This experimental study aimed to investigate the integrity of concrete produced in Zambia using rice husk ash (RHA) to partially replace cement. The primary goal was to carry out a cost–benefit analysis on the use of RHA in concrete. RHA was used to partially replace cement with ratios of 10 %, 20 % and 30 %. The 20 % cement replacement mix produced the optimum 18 MPa concrete strength results at a 0.5 water/binder ratio. This translated in cost reduction of concrete by 12.5 %, which is particularly significant for higher concrete volumes. The produced concrete is suitable for lightly loaded structures, such as foundation footings, surface beds and walkways to benefit low-income communities. The study further concluded that the RHA based concrete was more cost-efficient in structures that were close to areas of rice production due to reduced RHA transportation costs.

6

Microstructure silica leached by NaOH from semi-burned rice husk ash for moisture adsorbent

A’yuni D.Q., Subagio A., Hadiyanto H., Kumoro A.C., Djaeni M.

Archives of Materials Science and Engineering

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2021

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Vol. 108, nr 1

5--15

EN

Purpose: This work aims to study the water vapor adsorption property of fine silica particles from semi-burned rice husk ash. The semi-burned rice husk ash is selected as the raw material since it contains high silica and is easily found as a by-product of pottery furnace combustion. Design/methodology/approach: The silica adsorbent from semi-burned rice husk ash was prepared through a sol-gel method using various NaOH concentrations. In doing so, the different pH precipitation was also observed. Here, the fine silica powder was obtained by pulverizing dry sol-gel. The product characterizations were conducted based on water adsorption capacity at different air relative humidity. Findings: The results show no significant effects of different treatments in the extraction and gelation process. The fine silica particles exhibit large porous surfaces with agglomerated nano-sized particles that formed pores. This porous structure is related to the distributions of pore size of each sample, which mostly obey the mesoporous characteristics. From sorption isotherm, weak adsorbent-adsorbate bonding was observed and demonstrated multilayer adsorption of mesoporous materials. Research limitations/implications: The study of water adsorption was carried out at room temperature, which can change at any time, even though has no significant effect on the humidity. However, it is needed to study the adsorption in an incubated area to receive a constant temperature. Practical implications: The products namely silica prepared from semi-burned rice husk ash show a high moisture uptake, especially at a high relative humidity region. This property can be comparable with the other silica preparation methods. So, this product can be a highly potential adsorbent for air or gas dehumidification systems. Originality/value: The silica-based semi-burned rice husk ash as a water adsorbent is more sustainable than commercial silica. This is a positive contribution to find a potentially develop water vapor adsorbent with good adsorption capacity. Besides, the synthesis process is a simple and low-cost process.

7

Wpływ dodatków mineralnych na gęstość upakowania mieszanek trójskładnikowych

Pathania Akanksha, Shukla Abhilash, Vashisht Rajneesh

Cement Wapno Beton

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2020

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R. 25, nr 2

154--162

PL

Za pomocą metody Puntkego zbadano wpływ dodatku popiołu lotnego, popiołu z łusek ryżowych, metakaolinu oraz żużla o dużym rozdrobnieniu, na gęstość upakowania mieszanek trójskładnikowych. Wprowadzenie dodatków mineralnych o uziarnieniu mniejszym od cementu portlandzkiego zwiększa gęstość upakowania mieszanki, poprzez wypełnianie wolnych przestrzeni pomiędzy ziarnami cementu, a w efekcie powoduje wzrost wytrzymałości na ściskanie betonu. Głównym celem badań było zwiększenie gęstości upakowania poprzez częściowe zastąpienie cementu materiałami drobnoziarnistymi. Cement zastępowano w ilościach od 10% do 40%, co 5%. Zbadano wiele różnych kombinacji, a wyniki wykazały, że maksymalną gęstość upakowania wynoszącą 0,586 miały próbki o zawartości 75% cementu, z dodatkiem popiołu lotnego oraz żużla o bardzo dużym rozdrobnieniu, bez zastosowania superplastyfikatora. Dodatek superplastyfikatora jeszcze bardziej zwiększał gęstość upakowania, przy mniejszym stosunku wody do spoiwa.

EN

The effect of fly ash, rice husk ash, metakaolin, ultra-fine slag on the packing density of ternary mix was studied in this paper, using Puntke’s method of particle packing. The addition of these mineral additives, whose particle size is lower than that of the Ordinary Portland Cement, improves the packing density of cement, by filling the voids between the cement grains, which results in increased compressive strength of concrete. The main aim of this research was to increase the packing density by replacement of cement with fine materials. Cement replacement was carried out from 10% to 40% in steps of 5%. Many combinations were tested and results showed that a maximum packing density of 0.586 was achieved at 75% cement content along with fly ash and ultra-fine slag, without addition of the superplasticizer. Addition of superplasticizer further increased the packing at lower water to binder ratio.

8

Bond strength of concrete-filled hollow section with modified fibrous foamed concrete

Khairuddin S. A. A., Rahman N. A., Jamaluddin N., Jaini Z. M., Elamin A., Rum R. H. M.

Archives of Civil Engineering

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2020

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Vol. 66, nr 3

97--108

EN

The concrete-filled section of columns has been widely in construction used due to its structural elements. As a result, the usage of composite columns has recently increased all over the world. However, using foamed concrete alone does not result in much improvements in strength. Therefore, this paper examines the use of foamed concrete containing fibre to improve the strength of composite columns. Specifically, this study aims to determine the bond strength of concrete-filled hollow section (CFHS) with modified fibrous foamed concrete. Two types of fibre are used in this work, namely, steel fibre and polypropylene fibre, with rice husk ash (RHA) as a sand replacement to improve the compressive strength of foamed concrete. The CFHS with modified fibrous foamed concrete is tested by using the push-out method, and the results show that CFHS with steel fibre has a highest bond strength.

9

Przyspieszające działanie popiołu z łusek ryżowych na hydratację zaczynów cementowych z dodatkiem estru styrenowo-akrylowego

Wang R., Wang G.

Cement Wapno Beton

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2018

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R. 21/83, nr 5

396--406

PL

Popiół z łusek ryżowych jest dobrym oraz ekonomicznym dodatkiem przyspieszającym wiązanie i twardnienie zaczynów z cementu z dodatkiem estru styrenowo-akrylowego. Dodatek popiołu powoduje skrócenie początku i końca wiązania. Zależnie od dodatku popiołu czas wiązania zaczynu z polimerem może być nawet krótszy niż czas wiązania zaczynu cementowego, bez dodatku polimeru. Dodatkowo popiół z łusek ryżowych zwiększa wytrzymałość wczesną. Popiół z łusek ryżowych przyspiesza hydratację cementu w zaczynie z estrem styrenowo-akrylowym: znacznie skraca okres indukcji, zwiększa intensywność wydzielania ciepła hydratacji oraz stopień przereagowania cementu. Badania wykazały, że popiół z łusek ryżowych przyspiesza hydratację glinianu trójwapniowego oraz alitu, co powoduje powstawanie większych ilości ettringitu, fazy C-S-H. Popiół z łusek ryżowych ma dużą zawartość aktywnej krzemionki i może w zaczynie z cement-SAE reagować z wodorotlenkiem wapnia z utworzeniem żelu C-S-H.

EN

Rice husk ash [RHA] is an economical and effective material to accelerate the setting and hardening process of styrene-acrylic ester/cement [SAE-cement] composites. It makes the setting time of the SAE-cement as short as Portland cement or even shorter if necessary and enhances the early strength markedly. The RHA accelerates the hydration of SAE-cement: it significantly shortens the induction period of the SAE-cement hydration, increases the hydration heat evolution rate and hydration degree. RHA is a kind of active silica and reacts with Ca(OH)2 in the SAE-cement with C-S-H phase formation. RHA promotes the hydration of C3A and C3S and thus the formation of AFt and C-S-H.

10

Egipski popiół z łusek ryżowych jako materiał zastępujący cement

Ghorab H. Y., Rizk M., ElDirs F., Abdel Fatah A. M.

Cement Wapno Beton

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2016

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R. 21/83, nr 3

169--176

PL

Popiół z łusek egipskiego ryżu przygotowano spalając w laboratorium te łuski w 650°C przez 90 minut. Płukanie łusek powoduje, że uzyskany z nich popiół ma niską zawartością węgla i zawiera 90% krzemionki i 1,5% K2O. Zastąpienie cementu CEM I 42,5 N popiołem, o powierzchni właściwej 78 m2/g, w ilości 10%, 15% i 20%, poprawia uziarnienie spoiwa, jednak zwiększa jego wodożądność oraz ilość części nierozpuszczalnych. Zaprawa z 10% popiołu osiągnęła większą wytrzymałość na ściskanie po 28 dniach hydratacji; większa zawartość popiołu powoduje nieznaczny spadek wytrzymałości, jednakże wartości te mieszczą się w wymaganiach normowych.

EN

An Egyptian rice husk ash was prepared by burning the husk in the laboratory at 650°C for 90 minutes. Washing of the husks leads to low carbon ash, grey in color, with 90% silica and 1.5% K2O content. Replacement of CEM I 42.5 N with 10%, 15% and 20% ash of fineness 78 m2/g, improves the particle size distribution of the cement, increases its water demand and the insoluble residues. The reference mortar exhibit higher 28-day strength with 10% ash replacement; higher replacement ratio causes slight declination of the strength values, however still remaining within the standard specifications.

11

Utilization of recycle paper mill residue and rice husk ash in production of light weight bricks

Raut S., Ralegaonkar R., Mandavgane S.

Archives of Civil and Mechanical Engineering

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2013

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Vol. 13, no. 2

269--275

EN

Resource recovery and utilization of industrial by-product materials for making construction material has gained significant attention across the world. In this research study, recycle paper mill residue (RPMR) and rice husk ash (RHA) are utilized to improve the properties of bricks. This research study evaluated the feasibility of utilizing RPMR and RHA for making construction bricks. A homogeneous mixture of RPMR–RHA–cement was prepared with varying amount of RHA (10–20% by weight) and RPMR (70–80% by weight) and tested in accordance with the IS codes. Characterization of RPMR and RHA was performed using XRF, TG-DTA, XRD and SEM techniques. The SEM monographs show that RPMR has a porous and fibrous structure. The TG-DTA characterization demonstrated that RPMR can withstand temperatures up to 280 °C. The results indicate that RPMR-bricks prepared from RPMR–RHA–cement combination are light weight and meet compressive strength requirements of IS 1077-1992. This novel construction material serves objectives of resource recovery through prudent solid waste management.

12

Engineering properties of normal concrete grade 40 containing rice husk ash at different grinding time

Bakar B., Jaya R., Johari M., Wan M.

Advances in Materials Science

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2011

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Vol. 11, nr 1(27)

81-92

EN

The effect of rice husk ash with different grinding time on the engineering properties of concrete was studied. Eight rice husk ashes with different grinding were used in this investigation. Rice husk ash was used to partially replace Portland cement Type I at 15% by weight of cementitious material. The 100-mm concrete cube specimens were cast and cured in water for 7 and 28 days. The compressive strength of concrete was designed to achieve of grade 40 N/mm2 at 28 days. A superplasticizer was added to all mixes to provide workability in the range of 110 – 120 mm. However, the water to cement ratio (w/c) of the concrete was maintained at 0.49. Based on the results, the morphology of the rice husk ashes were changed by grinding. These appear to be an optimum grinding time of approximate 90 minutes which the compressive strength increased significantly. Generally, incorporation of RHA at varies grinding time can be decrease or increased the engineering properties of concrete extremely.