Raw Eggshell Research Articles

The Activation of Eggshell by Chemical and Thermal Treatment for Removal of Acid blue 92 Dye from Aqueous Solutions

In this paper the activation of egg shell by chemical and thermal treatment for removal of acid blue 92 (AB 92) dye from aqueous solution was studied. The raw eggshell (ES) was heated at 800oC for 2 h to obtain activated eggshell (AES), then AES was chemically treated by Zinc solution and triethylamine which resulted chemical-thermal activated eggshell (CTAES). The CTAES was analyzed by scanning electron microscopy (SEM), Fourier transform- infrared spectrophotometer (FT- IR), X-ray diffraction (XRD) and Brunauer, Emmett and Teller (BET). The operating factors such as pH (1-11), initial dye concentration (200 -1000 mg/L), amount of adsorbent (0.5-8 g/L) and adsorbent types (ES, AES and CTAES) were examined to obtain the maximum chemical oxygen demand (COD) removal percent of 90% and the maximum color removal percent of 98% within the 5 minutes of the equilibrium adsorption time. The experimental data were fitted to three rate models and isotherm models. The maximum adsorption capacity was evaluated as 480 mg/g. The results suggested that the CTAES can be effective adsorbent for removal of the AB 92 dye from aqueous solution.

Synthesis and characterization of calcium silicate insulating material using avian eggshell waste

This work focuses on the synthesis of calcium silicate insulating material via solid state reaction using avian eggshell waste as alternative calcium source. The calcium silicate formulations were mixed in a molar ratio SiO2:CaO (1:1) and fired at 1100°C for 24h. The calcium silicate formulations were characterized by XRD, TG-DTA, dilatometry, SEM/EDS, and thermophysical properties (thermal diffusivity, heat capacity per unit volume, and thermal conductivity). The synthesized calcium silicate materials are composed mainly of wollastonite with minor amounts of larnite and rankinite. It was found that a processing of the avian eggshell waste (raw eggshell waste and calcined eggshell waste) had an influence on the thermophysical properties. Calcium silicate pieces were prepared by uniaxial pressing at 82MPa, curing, and then testing to determine their use as thermal insulating material. The microstructure was evaluated by SEM. The results showed that both raw and calcined avian eggshell wastes could be used as an alternative calcium source in the calcium silicate formulation. It was found that the calcium silicate pieces reached low thermal conductivity values (0.252–0.293W/mK). Thus, the developed calcium silicate materials using avian eggshell waste act as a good thermal insulation ceramic material.

Removal of Phosphates from Water Using Eggshell Bio Sorbents

The present study focuses on the preparation and use of biosorbents produced from eggshells. Hen eggshells are produced as a by-product in large quantities by food manufacturers. The costs associated with eggshell disposal (mainly on landfill sites) are significant and expected to continue increasing as landfill taxes increase.The environmental significance of phosphorus arises from its role as a major nutrient for both plants and microorganisms. The adsorption efficiency of phosphate ions from the obtained biosorbents - raw eggshell powders - is studied at room temperature in static conditions. The effect of phosphate concentration and sorbent mass on the efficiency of the process is evaluated, as well as sorption kinetics are investigated. The structure, phase composition, porosity, specific surface area and morphology of obtained biosorbents is determined. The utilization of eggshells as an abundant, cheap and biodegradable material for the removal of phosphates is studied and discussed.

In vitro bioactivity studies of larnite and larnite/chitin composites prepared from biowaste for biomedical applications

Larnite (Ca2SiO4) was synthesized by the sol–gel combustion process by using raw eggshell powder as a calcium source and urea as a fuel. The main focus of this work is to convert biowaste into a biomedical material at a low-processing temperature. X-ray diffraction (XRD) pattern confirms the phase purity of the larnite and Fourier transform infrared (FTIR) spectra confirms the presence of characteristic functional groups of larnite. Scanning electron microscopy (SEM) image shows agglomerated particles with cauliflower-like morphology and energy dispersive X-ray spectroscopy (EDX) confirms the presence of the stoichiometric ratio of required elements. Atomic force microscope (AFM) images reveal the presence of pores on the surface of spherical particles. Larnite/chitin composites were fabricated into scaffold with different ratios of bioceramic to biopolymer (70:30, 80:20) to investigate the influence of the polymer content on the apatite formation ability in simulated body fluid (SBF) medium. XRD pattern and FTIR spectra of the scaffold immersed in SBF shows apatite deposition within 5 days. The deposition of hydroxyapatite (HAP) on the scaffold surface increases with the increase in polymer content of the composite.

Sulfur-based autotrophic denitrification with eggshell for nitrate-contaminated synthetic groundwater treatment

ABSTRACTEggshell is considered to be a waste and a significant quantity of eggshell waste is generated from food processing, baking and hatching industries. In this study, the effect of different sulfur/eggshell (w/w) ratios and temperatures was investigated to evaluate the feasibility of the sulfur-based autotrophic denitrification with eggshell (SADE) process for nitrate removal. The results showed eggshell can maintain a neutral condition in a range of pH 7.05–7.74 in the SADE process, and remove 97% of nitrate in synthetic groundwater. Compared with oyster shell and limestone, eggshell was found to be a desirable alkaline material for sulfur-based autotrophic denitrification (SAD) with no nitrite accumulation and insignificant sulfate production. Denitrification reaction was found to follow the first-order kinetic models (R2 > .9) having nitrate removal rate constants of 0.85 and 0.93 d−1 for raw eggshell and boiled eggshell, respectively. Sulfur/eggshell ratio of 2:3 provided the best efficiency on nitrate removal. Nitrate was removed completely by the SADE process at a low temperature of 15°C. Eggshell could be used for the SAD process due to its good effect for nitrate removal from groundwater.

Optimization of Cement Concrete using Eggshell Powder

Cement plays a vital role in this modern world. In fact high energy consumption is required to manufacture and transport the cement and causes air pollution including the release of greenhouse gases (Eg: carbon dioxide, SO2 and particulates.). To reduce the above effect considerably and to utilize the egg shell - derived as waste from industries, egg shell powder (ESP) is made as replacement for cement in concrete. As the egg shell waste is a serious matter in the egg-breaking industry, companies are paying more a year to dispose egg shell in landfills and the fills too had reached its capacity. The considered ESP is tried with cement in concrete so as to find its potential utility. Here an attempt was made to evaluate the effect of incinerated egg shell powder (IESP) and raw egg shell powder as a partial cement replacement. The initial setting time of cement concrete observed to be increases when cement replaced with egg shell powder. The effects of ESP with concrete in both the form were determined with 20%, 30%, 40% and 50% cement replacement. Also from the preliminary study it can be confessed that egg shell powder is considered as useful supplementary material in sustainable concrete production.

Properties of Waste Eggshell as Calcium Oxide Catalyst

The widespread usage of commercial calcium oxide (CaO) may lead to the depletion due to its non-renewable resources. CaO from eggshell waste has been studied to replace commercial CaO as it is cheaper and reduce cost of production. The objective of this study was to characterize CaO from waste eggshell. Raw eggshell was analyzed by thermal gravimetric analyzer (TGA) to obtain calcination temperature. The raw eggshell and calcined eggshell were characterized by x-ray fluorescence (XRF) and Fourier transform infrared (FTIR) spectroscopy to obtain elemental composition and functional group distribution. The morphologies of eggshell structures were determined by scanning electron microscope (SEM). TGA showed that the suitable temperature for calcination was 900oC. XRF and FTIR results showed that calcium carbonate (CaCO3) in the raw eggshell had been transformed to CaO. The irregular shape of raw eggshell also had been changed to regular shape for calcined eggshell.

Synthesis of spongy-like mesoporous hydroxyapatite from raw waste eggshells for enhanced dissolution of ibuprofen loaded via supercritical CO2.

The use of cheaper and recyclable biomaterials (like eggshells) to synthesize high purity hydroxyapatite (HAp) with better properties (small particle size, large surface area and pore volume) for applications (in environmental remediation, bone augmentation and replacement, and drug delivery systems) is vital since high-purity synthetic calcium sources are expensive. In this work, pure and mesoporous HAp nanopowder with large pore volume (1.4 cm3/g) and surface area (284.1 m2/g) was produced from raw eggshells at room temperature using a simple two-step procedure. The control of precursor droplets could stabilize the pH value of the reaction solution, because of the size of the needle (of the syringe pump used for precursor additions) leading to production of HAp with high surface area and pore size. The as-produced HAp revealed high ibuprofen (as a model drug) loading (1.38 g/g HAp), enhanced dissolution and controllable release of the drug via solute-saturated supercritical carbon dioxide.

Potential of Eggshell Waste for Pyrolysis Process

The eggshell waste which has potential mineral such as calcium oxide (CaO) was studied for biomass pyrolysis in a fixed bed reactor. The objective of this study was to characterize the CaO from waste eggshell and correlated the potential in pyrolysis process. Raw eggshells were analyzed by thermal gravimetric analyzer (TGA). Then, they were calcined at the temperature of 900oC for 1 hour with nitrogen gas. Raw and calcined eggshell were characterized by x-ray fluorescence (XRF). Non-catalytic and catalytic pyrolysis were done in the optimum pyrolysis condition with eggshell as a catalyst. XRF results showed that the percentage of CaO in raw eggshell was increased in calcined eggshell. Bio-oil product yield increased by 25.98% by using eggshell waste as a catalyst. CaO from waste eggshell improved the production of bio-oil in terms of quantity.

Egg shell membrane – a potential natural scaffold for human meniscal tissue engineering: an in vitro study

Enhanced human primary meniscal cell proliferation in autoclaved egg shell membrane.

Bioactive nanocrystalline wollastonite synthesized by sol–gel combustion method by using eggshell waste as calcium source

The sol–gel combustion method was employed to synthesize the nanocrystalline wollastonite by taking the raw eggshell powder as a calcium source and TEOS as a source of silicate. Glycine was used as a reductant or fuel and nitrate ions present in metal nitrate acts as an oxidizer. The phase purity of the wollastonite was analysed by powder XRD and the product is found to contain single-phasic wollastonite. FT–IR spectrum shows the characteristic peaks of the functional groups present in the wollastonite. SEM images show that particles are agglomerated and the particle size is found to be in the nanoregime. The calcination temperature was optimized based on the thermal analysis of the precursor. The bioactivity of wollastonite was investigated by immersing the scaffold in a simulated body fluid for 15 days at 37 °C and intermediate analysis of the surface by XRD shows the deposition of hydroxyapatite layer after 5 days.

Calcium phosphate bioceramics synthesized from eggshell powders through a solid state reaction

Abstract Everyday millions of tons of eggshells are produced as biowaste around the world. Most of this waste is disposed of in landfills without any pretreatment. Eggshells in landfills produce odors and promote microbial growth as they biodegrade. The present invention provides an environmentally beneficial and cost-effective method of producing calcium phosphate bioceramics (hydroxyapatite or tricalcium phosphate) from eggshell waste. In this investigation, heat treatment produced solid state reactions between eggshell powders and dicalcium phosphate dihydrate (CaHPO4·2H2O, DCPD) or calcium pyrophosphate (Ca2P2O7). When eggshell powders (CaO) and DCPD were heat treated at 1150 °C for 3 h, only a single hydroxyapatite (HA) phase was found; no diffraction peaks of starting materials and no β-TCP were observed. The XRD patterns of the product fabricated from raw eggshell powders (CaCO3) and Ca2P2O7 heat treated at 1100 °C for 3 h showed that almost only pure β-TCP remained with a trace amount of HA. The calcium phosphate ceramic synthesized from eggshell powders contains several important trace elements such as Na, Mg and Sr.

SINGLE STEP SINTERED CALCIUM PHOSPHATE FIBERS FROM AVIAN EGG SHELL

Different forms of calcium-phosphate (Hydoxyapatite, α-TCP, β-TCP, CDHA) minerals are found to be major component of bone tissue. Development of calcium-phosphate (CaP) based fibrous microstructures is of significant research interest worldwide owing to its improved mechanical properties and higher interconnectivity. Here we represent a method for single step sintered wet-spun Fibers of calcium phosphate from avian egg shells for biomedical applications. Raw egg shell powder was mixed with chitosan solution and Phosphoric acid. The mixture is milled in a ball mill overnight and then filtered. The slurry was de-aired using 100 microliter 1-octanol per 100 ml of slurry as antifoaming and wet spun in coagulation bath. Fiber was dried overnight and sintered at different temperatures for microstructure and phase analysis. Both green and sintered Fibers were physico-chemical characterized by SEM, EDX, XRD, TGA, DSC, FTIR, and stereo-zoom microscopy. The fibers obtained in this procedure are found to have highly porous interconnected structures which can provide good cell adhesion and therefore can be used for bioactive scaffold making.

Nanosized Hydroxyapatite Powder Synthesized from Eggshell and Phosphoric Acid

The present research describes synthesis of highly sinterable, nano-sized hydroxyapatite (HAp) powders using a wet chemical route with recycled eggshell and phosphoric acid as calcium and phosphorous sources. The raw eggshell was easily turned to CaO by the calcining process, and phosphoric acid was mixed with the calcined eggshell by the wet, ball-milling method. The crystalline development and microstructures of the synthesized powders and sintered samples were examined by X-ray diffractometry and scanning electron microscopy, respectively. The observed phases on the powder synthesis process were dependent on the mixing ratio (wt%) of the calcined eggshell to phosphoric acid and the heating temperature. The ball-milled, nano-sized HAp powder, which has an average particle size of 70 nm, was fully densified at 1300 degrees C for 1h. The Ca/P ratio for stoichiometric composition of HAp was controlled by adjustment of the mixing ratio.

Highly sinterable β-tricalcium phosphate synthesized from eggshells

Highly sinterable β-tricalcium phosphate (β-TCP) powders were fabricated by using recycled eggshells in addition with polyethylene glycol (PEG). A raw eggshell was easily turned to CaO by the calcining process and the calcined eggshell was mixed with phosphoric acid by the wet, ball-milling method. The observed phases of the heated mixtures were dependent on the mixing ratio (wt.%) of the calcined eggshell and phosphoric acid. A polyethylene glycol was added to the solution mixtures for making highly sinterable powders. In the process using the polymer, the final synthesized β-TCP powders showed smaller particle sizes and better sinterability in comparison with the synthesized β-TCP powders prepared without PEG. The ball-milled β-TCP powders employing PEG, were fully densified at the low temperature of 1150 °C without any transformation to α-TCP. In this study, the crystalline developments and Ca/P molar ratios of the synthesized calcium phosphate powders were studied by X-ray diffractometry and chemical analysis using ICP AES. In addition, the microstructures of the β-TCP powders and densified β-TCPs were examined using a scanning electron microscope.

Fabrication of Calcium Based Fine Ceramic Materials by Recycling Eggshell

A raw eggshell shows CaCO3 phase, and pure CaO can be obtained by calcination of the raw eggshell. And the morphology of the calcined eggshell is grape-type granular with uniform particles. By using the recycled eggshell, biocompatible and highly sinterable calcium phosphate bio-ceramics were successfully fabricated, such as hydroxyapatite (HAp) and b-tricalcium phosphate (b-TCP), and wollastonite (CaSiO3). The observed phases and microstructures on the powder synthesis process are dependent on the content of eggshell and calcination temperature. In this study, the crystalline development and the microstructure of synthesized powders and the densified specimens are examined by X-ray diffractometry and scanning electron microscopy.

Utilization of Egg Shells and Phosphoric Acid as a Source of Phosphorus and Calcium in the Diet of White Leghorn Cockerels

Mathematical calculations, chemical analyses, and physical characteristic determinations of phosphoric acid-egg shell combinations were made to ascertain the feasibility of utilizing such combinations as phosphorus and calcium sources in the diet of the baby chick. Two combinations of phosphoric acid and raw egg shell were fed as sources of both phosphorus and calcium to three replicates of White Leghorn cockerels from hatch to 21 days of age in two experiments. A degerminated corn meal diet which contained 0.30% phosphorus and 0.21% calcium was used as a basal. Graded levels of both acid-shell mixes and monosodium phosphate were added to yield supplemental phosphorus levels of 0.05, 0.10, and 0.15% from each source respectively. Two calcium levels were fed at each phosphorus level. Desired calcium levels, above that supplied by the shell products, were obtained by adding ground limestone. Final body weights were obtained by replicate after 21 days on trial and four chicks in each replicate were sacrificed at this time for bone ash determinations.There appeared to be no major physical or biological problems associated with mixing or feeding the acid-shell mixes. Within treatment levels, chicks fed the acid-shell mixes as a source of phosphorus and calcium had body weight and bone ash values comparable to those fed monosodium phosphate. Phosphorus and calcium in both acid-shell mixes were available to the chick for growth as well as bone mineralization.