Nano Calcium Oxide Research Articles

The Contribution of Nano-Alumina to Ultra-High-Performance Cement-Based Systems.

In the last decades, nano-silica (NS), nano-alumina (NA), and nano-calcium oxide (NC) particles have been incorporated into cementitious materials, and it seems that each one of them contributes uniquely to the materials' properties. This research explores the influence of each nanomaterial on the fresh properties of cement pastes and their compressive strength evolution over one year. Low proportions (1.5% by weight) of nanomaterials were added to cement pastes, and their fresh properties, such as heat of hydration and X-ray diffraction patterns in the first hours, were analyzed. The compressive strength and open porosity were also measured long-term. The acceleration of hydration heat in NA-cement pastes is linked to enhanced hydration product formation at early ages. Among the tested nanomaterials, NA increased compressive strength by 10% at later ages. Although the fresh properties of NC-cement pastes remained unaffected, their open porosity decreased by 54% at 28 days. In contrast, the increase in heat of hydration in NS-cement pastes did not result in significant strength improvement. Based on these findings, NA was selected for ultra-high-performance cement (UHPC)-based material use. Its incorporation not only preserved the ultra-high-performance (UHP) properties but also provided additional benefits such as an increase in compressive strength under a CO2 atmosphere. Through detailed analysis, this research establishes that nano-alumina incorporation optimizes the microstructural development and compressive strength of ultra-high-performance cement-based systems, presenting a novel advancement in enhancing the mechanical properties and durability of these materials under various environmental conditions.

The influence of rice bran oil and nano-calcium oxide into bitumen as sustainable modifiers

Bio-oils are increasingly used to enhance petroleum bitumen’s intermediate and low-temperature characteristics regarding their economic and environmental benefits. Research has shown a beneficial impact of nanomaterials on altering bitumen’s high-temperature characteristics. The present study uses a mixture of rice bran oil and nano-calcium oxide to improve the performance of bitumen in all three temperature conditions. Rice bran oil was added to pure bitumen at doses of 3, 5, and 7 % relative to the weight of bitumen. The rheological tests (dynamic shear rheometer, multiple stress creep recovery, linear amplitude sweep, and bending beam rheometer) demonstrated that using rice bran oil in bitumen enhanced its performance at intermediate and low-temperatures but declined its performance at high-temperatures. Therefore, to improve the performance at high-temperatures, the bituminous sample containing 5 % rice bran oil was combined with 1, 3, and 5 % nano-calcium oxide, followed by repeating the rheological tests on them. The samples modified with nano-calcium oxide showed increased friction and shear stress, viscosity, and rutting parameters. Besides, the samples exhibited reduced sensitivity to aging compared to the bio-oil samples. However, the non-recoverable creep compliance and percentage of recovery showed improvements. The fatigue life of bio-oil samples decreased after adding nano-calcium oxide. However, the fatigue life remained higher than the base bitumen sample when adding 1 % nano-calcium oxide. Fourier-transform infrared spectroscopy analysis showed that a new chemical reaction occurred due to adding nano-calcium oxide to bitumen containing rice bran oil. Besides, the scanning electron microscope image revealed that the nano-calcium oxide particles are uniformly and homogeneously distributed within the bitumen sample containing 5 % rice bran oil. Consequently, the mix containing 5 % rice bran oil and 3 % nano-calcium oxide increases the resistance against high-temperature failures and improves the low-temperature performance compared to the base bitumen sample.

Optimization of Biodiesel Production from Waste Cooking Oil Using Nano Calcium Oxide Catalyst

AbstractThe use of nano calcium oxide as a catalyst in biodiesel production has gained attention due to its high catalytic activity, low cost, and environmental friendliness. It efficiently converts triglycerides to fatty acids and methyl esters. In the present study, nano CaO was prepared by precipitation and characterized by various techniques. The results showed that the nano CaO has high purity, nanoscale crystal size, good thermal stability, and high specific surface area. Biodiesel was produced by transesterification from waste cooking oil, methanol, and the nano catalyst. Response surface methodology was applied to predict the optimum parameters for the production of the biodiesel based on its yield. The produced biodiesel was characterized by FTIR spectroscopy and GC‐MS and evaluated according to ASTM D6571.

Biocompatibility of Newly Prepared Nanocalcium Oxide Based Root Canal Sealer (In Vivo study)

Biocompatibility of Newly Prepared Nanocalcium Oxide Based Root Canal Sealer (In Vivo study)

Synthesis and characterization of calcium oxide nano particles obtained from biowaste and its combustion characteristics in a biodiesel operated compression ignition engine

The goal of this research is to use calcination to make calcium oxide (CaO) nano additives that can be used as fuel additives. Spectrum investigations using X-ray Diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR) established the synthesis of nano particles. The fuel is a waste cooking oil bio diesel of B20 blend (20% biodiesel and 80% diesel) mixed with nano Calcium oxide additives in five concentrations: 25, 50, 75, 100 and 125 ppm. The qualities of the fuel are examined in line with the criteria of the American Society for Testing and Materials (ASTM). The combustion investigation of these fuel samples in a four-stroke compression ignition engine coupled to an eddy current dynamo-meter found a 3% improvement in average brake power. All of the fuel samples examined have a combustion efficiency of 90–98%. The CaO nano additions improved the heat release rate (HRR) of the engine. The average cylinder pressures (CP) of the additive blended samples are also higher. Peak pressures of the biodiesel samples investigated in the experiment ranged from 1° to 15° crank angle after top dead centre (aTDC) under all conditions. The mean pressure rise rate (MPRR) for WCOB20 + CaO25ppm is 4.7 bar/degree CA. According to this study, the synthesised micro CaO particles appear to be a viable candidate for usage as additives to improve the combustion characteristics of engines powered by bio-diesel blends. However a complete study on performance, emission along with combustion characteristics is required to evaluate the prominence of this fuel with prepared nano additives. In future, calcium oxide nano catalysts for the production biodiesel may also be an viable alternate.

Synthesis of Nano-Calcium Oxide from Industrial Brine Sludge Waste with Nanocrystalline Cellulose (NCC) as Addictive/composites and Modelling using Artificial Neural Network (ANN) for Biodiesel Production

Biodiesel production as a fuel in diesel engines has expanded dramatically in recent years and is likely to increase more in the near future. Increasing biodiesel consumption requires optimized production techniques that allow for large production capacities, simplified operations, high yields, and the usage of more cost-effective feedstocks such as waste oils and fats. In this study, biodiesel was produced from waste vegetable oil (WVO) and Methanol (CH3OH) in the presence of a catalyst which was derived from industrial waste that mainly consists of Calcium Carbonate (CaCO3). The produced nano-particle catalyst was characterized by using Fourier Transform infrared (FTIR), Scanning Electron Microscope (SEM) and X-ray diffraction (XRD). The optimum operating conditions for the highest biodiesel yield after applying the artificial neural network (ANN) approach was found to be 96.41 % yield at a temperature of 55 °C, catalyst loading of 1.25 % w/v, Methanol to oil ratio of 1:5 w/w and reaction time of 75 min. The FTIR showed the presents of CaO and NCC functional group. SEM image revealed that the produced catalyst is more porous, with small particle size, and XRD pattern presented the presence of cellulose (NCC) and Calcium Oxide (CaO) nano particles in the synthesized catalyst. The R2 of 0.977 was found to be for the mathematical models to predict biodiesel production.

Preparation Technology and Properties of Carbon-Reinforced Recycled Aggregate Concrete and Mortar

Crushing the demolished waste concrete as aggregate to prepare fresh concrete may cause aggregate internal damage leading to strength reduction. To counter this issue, in the current study, the recycled aggregate is mixed with nano-calcium oxide in a vacuum reactor, and then a high concentration of carbon dioxide is introduced to fill the internal damages of the recycled aggregate. A layer of hydrophilic alkaline substance is formed on the surface of recycled aggregate to absorb carbon dioxide, which improves the strength of recycled aggregate particles and the bonding performance of aggregate-cement interface area. The test results show that the mechanical properties of recycled aggregate particles are improved after vacuum carbon strengthening, and the vacuum carbon strengthening effect of recycled aggregate with large particle size is more obvious. Compression strength of concrete and mortar prepared by vacuum carbon-reinforced aggregate is observed to be 13.6% and 30% higher than ordinary recycled concrete, respectively. Also, the proposed recycled aggregate improvement method manifests a 21.1% reduction in carbon emissions. These findings offer crucial parameters for the engineering use of recycled concrete, promote new ideas to reduce carbon emissions caused by fresh concrete production, and provide an important reference for the sustainable recycling of waste concrete.

Application of Calcium-Based Nanomaterials in Art Sculpture Reinforcement Technology.

In order to solve the problem of the reinforcement effect of art sculpture, the author proposes the application of a calcium-based nanomaterial in the reinforcement process of art sculpture. This application mainly passes the unconfined compression test, direct shear test, penetration resistance test, and disintegration test, and an in-depth evaluation of the reinforcement effect of different calcium-based reinforcement agents on the site soil was carried out from the perspective of mechanical strength and water stability. The results showed the following: Compared with the untreated samples, the unconfined compressive strength of the samples treated with nano-calcium oxide and nano-calcium hydroxide increased by 13.5% and 25.9%, respectively, and the cohesion increased by 69.8% and 97.7%. Conclusion. Calcium-based nanomaterials fill in the pores between soil particles to support the soil particles, which greatly improves the mechanical strength and water stability of the specimen.

Evaluation of CO2 adsorption capacity with a nano-CaO synthesized by chemical combustion/ball milling

Abstract The adsorption of CO2 on a nano-calcium oxide (nano-CaO) adsorbent was investigated under different conditions of temperature and supply pressure, considering kinetic, isotherm, and thermodynamic parameters. CaO is a crystalline material with a high surface area and nanosized particles with high porosity, which showed rapid initial CO2 adsorption rates in the moderate temperature range studied. The adsorption was well described by the pseudo-second-order and the intraparticle diffusion kinetic models. The Langmuir isotherm model fitted the experimental data well, indicating a monolayer-type process. The thermodynamic parameters revealed that the CO2/nano-CaO adsorption was endothermic, not spontaneous, and proceeded via physical and chemical processes. The activation energy value confirmed that the mechanism involved is a chemical process. In addition, the nano-CaO adsorbent could be regenerated five times without any significant loss of performance or properties. All the obtained results reveal that this porous nanoadsorbent has huge potential to be applied for CO2-capture technologies on a large scale.

Optimization of the Process of Metal NanoCalcium Oxide Based Biodiesel Production through Simulation Using SuperPro Designer

This study evaluates improvements made to a biodiesel production process from Chlorella sp. micro algae in a locomotive pilot plant using simulation. Energy and the main variables of the operation such as temperature, reaction time, alcohol molar concentration, vegetable oil, and use of homogeneous and heterogeneous catalysts and their concentration, mixing intensity, and moisture control were collected from operational data, and mass balances were tested in the SuperPro Designer retail package v.9.5. The result was an increase in the efficiency of the process of obtaining company biodiesel from 86% to 92% by volume, the same that were scaled taking into account the species’ production locality, and the results obtained showed that 26% was met by obtaining 10 MM (millions) of liters of biodiesel from the scaled plant.

The role of nano-modified coverings against salt attack

The penetration of chloride and sulfate salts can cause detrimental damage in historic structures. Porous building materials that are usually engaged in such structures are susceptible to penetration of water that also permits the penetration of diluted salts. Coverings have been traditionally used as protective layers in such structures. In the present study, the performance of nano-modified, lime-based layers that can have a protective role against salt penetration, is evaluated. Lime pastes with nano-alumina (NA) and combination of NA and nano-calcium oxide (NC), as well as lime-pozzolan pastes with nano-silica (NS) and NA-NC combination were produced. The nano-modified materials were applied on ceramic bricks and the systems’ performance was evaluated by capillarity test, freeze-thaw cycles and resistance against salt penetration. NA improved the chloride absorbing ability of lime-based sacrificial layer and both NS and NA-NC combination improved the sulfate absorbing ability in lime-pozzolan based sacrificial layers. Additionally, the freeze-thaw cycles (from −10 °C to 40 °C) revealed that NA prevents expansion and spalling of the lime-based layers and that NA-NC combination offers durability and higher sulfate absorption ability to lime-pozzolan covering.

Enhancement of mechanical and toughness properties of carbon fiber-reinforced geopolymer pastes comprising nano calcium oxide

Enhancement of mechanical and toughness properties of carbon fiber-reinforced geopolymer pastes comprising nano calcium oxide

Removal characteristics of Pb(II) and Cd(II) from aqueous single metal solutions by vermicompost combined with nano-CaO

ABSTRACT Vermicompost (CV) and nanomaterials have been identified as potential amendments to adsorb environmentally toxic heavy metals. This study analyzes multi-aspect properties of CV and its nanocomposite (CV-nCa) with nano calcium oxide (nCaO), which include pH, electrical conductivity (EC), cation exchange capacity (CEC), ash content and surface characteristics, aiming to compare their potential for removing aqueous Pb(II) and Cd(II). The results demonstrated that CV-nCa had a higher pH, EC, CEC, ash content, pore parameters and specific surface area than CV. Adsorption isotherm studies showed that CV-nCa had a higher adsorption capacities for Pb(II) and Cd(II), with the maximum adsorption capacities being 255.1 mg/g and 137.7 mg/g. The adsorption rates (ARs) by CV-nCa were both above 99.72% within the initial concentration of Pb(II) being 200–800 mg/L and Cd(II) being 100–200 mg/L. In addition, CV-nCa can effectively remove Pb(II) and Cd(II) within a wider pH range (3–6) and a lower mass concentration (MC) of 4 g/L. Kinetic studies showed that the Pb(II) and Cd(II) adsorption by CV-nCa were both best fitted with the pseudo-second-order model. FTIR analysis demonstrated that the interaction of CV and CV-nCa with Pb(II) and Cd(II) mainly depended on thearomatic/aliphatic acids, some primary/secondary alcohols and some silicate and carbonates. XRD analysis showed that the addition of nCaO into CV mainly increased CaCO3 content and affected the adsorption characteristics. Thus, combining nCaO with vermicompost may broaden heavy metal remediation and vermicompost utilization in the environment.

Synthesis of Sustainable and High Purity of Quicklime Derived from Calcination of Eggshell Waste in a Laboratory-Scale Rotary Furnace

Quick lime or calcium oxide has attracted significant attention as a sustainable material to be used as fillers and catalysts in a broad range of industries. The quick lime derived from calcination of eggshell waste in a laboratory-scale rotary furnace is reported in this study. The eggshell waste was prepared by washing several times, drying in the sun, grinding and sieving through a 250 micrometers sieve size. Calcination of the sieved eggshells waste was conducted in a single zone rotary tube furnace at 800 °C with 5 degree slope and at 1 rpm. Both physical and chemical properties of the calcium oxide derived from the calcination of eggshell waste were systematically investigated by various scientific instruments. The results from powder X-Ray Diffraction (PXRD) and X-Ray Fluorescence: (XRF) showed that most of the calcium carbonate in the eggshell waste was thermally transformed to nano-calcium oxide with mean crystallite size of 47.5 nm and with a purity of 97.8%. The results from this study indicated the optimum conditions and the possibility for mass production of nano-calcium oxide via rotary furnace and have shown that the obtained nano-calcium oxide is comparable to the commercial chemical.

EXPLORATION OF EFFICIENCY OF NANO CALCIUM OXIDE (CaO) AS CATALYST FOR ENHANCEMENT OF BIODIESEL PRODUCTION

Present work proposes on the synthesis of nano calcium oxide derived from waste cockle shell (Anadara granosa) and applied as heterogenous catalyst in biodiesel production via transesterification reaction under reaction parameter 15:1 methanol to oil ratio, 5 wt.% catalyst and 3 hour reation time and constant temperature at 65 ± 2 °C. The waste cockle shell was prepared in nano size via ball mill technique which was run for 36 hours at 350 rpm speed and then calcined at 900 °C for 2 hours to decompose calcium carbonate, CaCO₃ into nano calcium oxide, n-CaO. The catalyst was characterized by particle size analyzer, Transmission Electron Microscopy, Field Emission Scanning Electron Microscope, Surface Area Analyser, X-Ray Diffractometer, Fourier transform infrared, Hammet indicator and benzoic acid titration. Particle size of n-CaO catalyst was found within the range of 29 nm to 67.5 nm. Specific surface area of synthesised n-CaO is 8.41 m²/g with basicity strength of 0.055 mmol/g. Methyl ester conversion of palm oil with n-CaO as a catalyst was 88.87 wt.%

Nanoparticles controlling self-healing properties in cement pastes

The ability to control self-healing of cement by using nanoparticles was investigated in the present work. The physico-mechanical properties, the mineralogical composition and the microstructure observation were tested before cracking at 28 days. After the formation of cracks the healing capability under water immersion was detected by optical observation. The self-healing was supported by porosity reduction, new formed materials’ formation in micropores and cracks’ width elimination in the pastes. The addition of 1.5%wt nano-calcium oxide (NC) healed the cracks by 100% on some areas and by 61% in other areas, based to the crack width measurement. The combination of NC and nanosilica (NS) by 1.5%wt respectively, led to crack width decrease, through the formation of efflorescence-like crystals. Overall, the use of nanoparticles in low proportions is proposed for self-healing properties promotion in cement pastes.

COMPARATIVE STUDY OF REMOVAL POLLUTANTS ( HEAVY METALS) BY AGRICULTURAL WASTES AND OTHER CHEMICAL FROM THE AQUEOUS SOLUTIONS

This study included the application of some experiments in the chemical treatment of some heavy metals elements by preparing biological surfaces that are adsorbed from natural and other chemical substances, as in preparing activated carbon prepared from charred pistachio shell with concentrated H2SO4 and Nano-Calcium Oxide prepared from CaCL2.2H2O with NaOH . The prepared materials were diagnosed with spectral techniques where the FTIR infrared spectrum proved the formation of carbonyl, hydrogen and oxygenated of the surface in activated charcoal and the hydroxyl and calcium oxide groups in the nano-calcium oxide, as the FE-SEM surface morphology was proven to form on coal blocks The surface is a network of irregular holes and a network of microscopic holes regular on the surface of nano- calcium oxide. As for X-ray diffraction technology, the crystal structures of the surface, its shapes and sizes, are shown, and that activated charcoal consists of that Many types of carbon in the form hexagonally and cuboid and rhomboid with a right angle, while technical proven size of the crystalline calcium oxide nanoscale which ranges between (54.68-67.86nm) cube-shaped. PIAC activated charcoal and n-Calcium oxide were used as sorbents in the removal of, Cd + 2, Pb + 2 ions from aqueous solutions, a study of the effect of pH, contact time, multiple weights for surface and the primary concentration of ions in a horizontal removal method , and the removal of minimal concentrations of ions in large volumes of solutions by the process of preconcentration .

The Influence of Curing Regimes in Self-Healing of Nano-Modified Cement Pastes.

The present study proposes nano-calcium oxide (NC) and nano-silica (NS) particles as healing agents in cement pastes, taking into account the curing conditions. Two series of specimens were treated in water and under wetting-drying cycles. The addition of NC (1.5%wt of binder) triggered early healing since cracks were healed within 14 days in underwater immersion and before 28 days at wetting-drying cycles. Attenuated Total Reflectance (ATR) spectroscopy and SEM analysis revealed that the healing products were mainly aragonite and calcite in water conditions and more amorphous carbonates under wetting-drying cycles. The combination of NS and NC (3.0%wt in total) offered healing under both curing conditions before 28 days. The presence of NS assisted toward porosity refinement and NC increased the carbonates’ content. The newly formed material was dense, and its elemental analysis by SEM revealed the C-S-H compounds that were also verified by ATR.

Nano Calcium Oxide Incorporated Hydrocolloid Dressings for Wound Care

The study aimed to formulate hydrocolloid dressings incorporated with nano calcium oxide for effective wound healing. Hydrocolloid dressings create an insulated, moist environment in the wound bed for controlling the exudate and promoting autolytic debridement. Calcium ions play an important role in wound response and are considered to be an initial trigger in our immune response to healing, and research has shown that Ca2+ in the external medium is essential for wound repair. Seventy five parts per million of nano calcium oxide (NCO) obtained by thermal decomposition of calcium nitrate at 450 °C was used in the preparation of hydrocolloid dressings along with varying concentrations of micronized xanthan gum and HPMC. The dressings were evaluated for their surface characteristics, thickness, mechanical properties, folding endurance, pH, viscosity, swelling studies, water vapor transmission, and in vivo wound healing activity. The average particle size of NCO was found to be 307.8 nm. The SEM (scanning electron microscopy) analysis of the dressing revealed a porous surface and EDX (energy dispersive X-ray spectroscopy) characterization showed intense peaks of calcium and oxygen. The formulated dressings possessed uniform thickness, flexibility, and mechanical strength. The percentage of wound contraction was higher in wounds treated with formulated hydrocolloid dressings in comparison to standard commercial product (DuoDERM® hydrocolloid dressing) and control (untreated) group. The wound healing properties of hydrocolloid dressings were confirmed by histopathological analysis. Nano calcium incorporated hydrocolloid dressings with enhanced wound healing activity were developed successfully.

Behavior Evaluation of Bituminous Mixtures Reinforced with Nano-Sized Additives: A Review

This article presents a comparative review of the most commonly used nano-additives for bituminous mixtures: nanoclays (NC), nanosilicates, carbon nanotubes (CNTs), graphene nanoplatelets (GNPs), nano-calcium oxide (CaO), and nano-titanium dioxide (TiO2). In this study, the mechanical behavior of the obtained additive mixture is evaluated. According to the revised literature, the results strongly depend on type, concentration, and dispersal of used nano-additive. In fact, it has been seen that simple shear mixing followed by sonication homogenizes the distribution of the nanoparticles within the bituminous matrix and favors the bonds’ formation. The viscosity of the mixture of bitumen with nanoparticles improves with the increase of the percentage of additive added: it indicates a potential improvement to permanent deformation and rutting. Another benefit is an increased resistance of the binder to aging. Furthermore, it has been shown that the nanoparticles are able to prolong the service life of a bituminous mixture by means of various interdependent chemical–physical mechanisms that can influence the resistance to fatigue failure or the ability to self-heal. However, the effectiveness of these improvements depends on the particle type, added quantity and mixing technique, and the tests carried out.