Factors Affecting the Particle Size of Bio-Calcium Carbonate Synthesized from Industrial Eggshell Waste

Abstract

Calcium carbonate is broadly used as a catalyst support, filler, additive, and reinforcement in several types of industry e.g. chemical, food, and biomedical industry. Recently, eggshell waste has attracted much attention for the purpose of calcium carbonate production due to its compost about 96% calcium carbonate. However, direct use of egg shells as filler material can probably cause product defects. In this research, calcium chloride was extracted from chicken-eggshell waste followed by precipitation of micron size calcium carbonate. The effect of agitation time, the initial concentration of calcium chloride and synthesis temperature on particle size, and selected physicochemical properties of this precipitated calcium carbonate (PCC) were investigated. Scanning electron micrographs of the prepared materials illustrated that all of the PCCs obtained from these experiments exhibit uniform-round shape. The laser diffraction results show that the median size of the PCC particles increased significantly from about 6 µm to 19 µm with increasing agitation time and with decreasing initial concentration of calcium chloride. However, increasing the synthesis temperature from 30°C to 160°C only slightly increased the median size of the PCC particles. The results of X-ray diffraction indicated that both agitation time and initial concentration also have an effect on the crystalline morphology of the PCCs. In addition, calcite crystalline phase became dominant over the other crystalline phases when agitation time and initial concentration were increased. In comparison, PCCs synthesized from this eggshell waste have much smaller median particle size than commercial calcium carbonate. Furthermore, the purity of the PCC derived from shell waste was comparable to commercial calcium carbonate. This facile synthesis is environmentally friendly and cost effective.

Tuning polymorphs of precipitated calcium carbonate from discarded eggshells: effects of polyelectrolyte and salt concentration

“…1E-a ), the additional new XRD peaks appear at 2 theta of 21.07°, 25.05°, 27.20°, 32.94°, 43.33°, 50.15°, and 57.53°, corresponding to the presence and formation of vaterite polymorph crystal structure. 34 …”

“…1E-a), the additional new XRD peaks appear at 2 theta of 21.07 , 25.05 , 27.20 , 32.94 , 43.33 , 50.15 , and 57.53 , corresponding to the presence and formation of vaterite polymorph crystal structure. 34 Therefore, the XRD results can conrm the coexistence of vaterite and calcite polymorphs aer the precipitation of calcium carbonate particles. However, the intensities of vaterite peaks are relatively lower in 0.03 M (Fig.…”

Biogenic calcium carbonate derived from waste shells for advanced material applications: A review

“…Frontiers in Materials frontiersin.org Frontiers in Materials frontiersin.org a related study, Putkham et al (2018) have synthesized pure calcite calcium carbonate from eggshell waste via a simple liquidliquid precipitation method. The eggshells were digested in hydrochloric acid with different concentrations to obtain calcium chloride solution first, which later reacted with sodium carbonate in various temperatures and agitation time to obtain different polymorphs of calcium carbonate.…”

Production of Bio-Calcium Oxide Derived from Hatchery Eggshell Waste Using an Industrial-Scale Car Bottom Furnace

“…Solid hatchery waste comprises empty eggshells, dead embryos, dead chicken, and viscous liquid from decaying tissue and eggs [2]. In Thailand, the amount of hatchery eggshell waste generated annually is about 876,000 tons and most of this waste is usually discarded in landfills, requiring high management costs [3]. This large amount of waste leads to several environmental impacts, e.g., odor nuisance, ground water pollution, and social conflict.…”