High-energy Milling Treatment Research Articles

Instant Synthesis of Cu2O Nanoparticles by a Selective Ionic Exchange in Nanozeolite 4A

This study presents a novel method for synthesizing Cu2O nanoparticles by employing ion exchange within a modified nanozeolite 4A matrix. The nanoparticles had a consistent particle size, predominantly around 6[Formula: see text]nm, with a narrow distribution. Nanosizing of the zeolite was achieved through high-energy milling treatments, thereby enhancing the surface-to-volume ratio. A band close to 700[Formula: see text]cm[Formula: see text] was observed in the FTIR spectrum, potentially indicating that zeolite downsizing was related to symmetric stretching of the Si–O bond postmilling. Furthermore, a distinctive band corresponding to Cu(I)–O stretching vibrations was identified at approximately 600[Formula: see text]cm[Formula: see text]. Additionally, optical absorption analyses of the UV-Vis spectrum revealed two characteristic bands attributable to Cu2O nanoparticles at 370[Formula: see text]nm and 470[Formula: see text]nm. These findings have led to advancements in resource use and promoted sustainable and environmentally friendly production practices.

Effect of variations in milling speed with high energy milling treatment on surface area of biochar material

Biochar is a renewable and abundant carbon source and is useful for increasing food security and plant diversity in areas with poor soil conditions, lack of organic matter, lack of water availability and chemical fertilizers. Biochar micro porous structure can be produced from corncob material which inherits the architecture of raw materials. To increase the surface area of the biochar material, high energy milling treatment was carried out in this study by varying the speed of milling in the same milling time. Milling time is carried out at 3 hours with milling speeds varying of 300, 500 and 700 rpm. The samples were characterized by X-ray diffraction, scanning electron microscope (SEM), particle size analyser (PSA), and surface area analysis - Brunauer, Emmett and Teller (SAA-BET). The test results show that at speed of 300, 500 and 700 rpm it has produced biochar with a particle size of 947,9; 868,5 and 799,2 nm, respectively. While the SAA-BET test has produced a surface area of 10.115; 15.889 and 18.303 m2/g. This study describes an increase of surface area when compared without milling treatment which has a surface area of 7917 m2/g.

High-energy alkaline milling as a potential physical and chemical cornstarch ecofriendly treatment to produce nixtamalized flours

In this study, hard corn grains were nixtamalized (alkali-heat treatment) by a high-energy ball mill to investigate the effects on its physicochemical, textural, and microstructural properties. Ball milling modifies the structure and properties of cornstarch. The gelatinization peak of starch was evidenced and thermal and pasting properties were significantly affected. With regard to rheological properties, the viscosity peak increased from 2454 cP in traditional nixtamalized flour to 4294 cP in high-energy milling treatments with 1.4% of Ca(OH)2 and 20% moisture content, C1.4, while enthalpy ranged from 3.5 to 0.34 J/g, respectively. High-energy milling influenced the Fourier-Transform InfraRed Spectroscopic (FT-IR) patterns. All of the samples of the corn-grain starches presented the typical A-type X-ray diffraction pattern. The crystallinity of starch from CG showed a lower intensity in peaks 2θ ~ 15 and 23° compared with starch from WG and YG. The textural properties of the masas were influenced, adhesiveness was reduced, but cohesiveness was increased by the addition of Ca(OH)2. In the structural characterization by E-SEM, the control presented a greater amount of agglomerated starch granules, followed by the high-energy milling treatments. The results suggest that high-energy alkaline milling could be a potential physical and chemical method to modify corn-starch properties and obtain nixtamalized products.

Effect of High-Energy Milling on Bioactive Compounds and Antioxidant Capacity in Nixtamalized Creole Corn Flours.

This study aimed at evaluating the effect of high-energy milling (HEM) and traditional nixtamalization (TN) on bioactive compounds and antioxidant capacity in nixtamalized creole corn flours obtained from a maize genotype cultivated under rainy temporal conditions in the Mexican semidesert. Four creole grains, including San José de Gracia white and blue (WG and BG), Negritas (NG), and Ahualulco white corn grains (SG), were used. For HEM nixtamalization, corn grains were hammer-milled; then, two different conditions were evaluated: treatment H1, with raw flours with 14% moisture content and 1.1% Ca(OH)2, and treatment H2, with raw corn flours with a 23% moisture content and 1.4% Ca(OH)2. The TN process was utilized as a control. TN recorded significant losses in luminosity value L* (p< 0.05), while HEM nixtamalized blue corn flours remained close to -b* values, that is, near to those of raw flour. Anthocyanin content showed higher content values in HEM treatments compared with TN (759.55 and 252.53mg cyanidin 3-O-β-D-glucoside (C3G)/kg, respectively) (p< 0.05). Total soluble phenolic content was higher in HEM nixtamalization compared with the traditional process, except for WH2 and SH2 (H2 treatment for WG and SG). Two redundant radical scavenging assays were used: antioxidant capacity (DPPH assay) exhibited less value in nixtamalized flours than in raw flour (p< 0.05). Antioxidant activity by (ABTS) assay was higher in HEM than in TN. Nixtamalized flours produced by HEM demonstrated more improvement in nutraceutical properties than those produced employing TN.

Behavior of high-energy-milling-activated eggshells during thermal treatment

The main object of investigations in this work is the chicken eggshells. The effective high-energy milling (HEM) treatment and utilization of chicken eggshells (ES) as a bio-waste waste have been investigated in environmental and economic interest. The composition of the ES includes mainly inorganic (94 % calcium carbonate as calcite, 1 % calcium phosphate and 1 % magnesium carbonate) as well as organic matter (4 %). During HEM, the mechanical activation process takes place, which leads to improvement of materials properties. The HEM-activated ES samples were characterized by thermal analysis, Fourier transform infrared spectroscopy and scanning electron microscopy. The decarbonization was carried out using the thermal methods with Ar flow gas. We established that the thermal properties of the ES samples change considerably due to HEM treatment. The changes appear as: (1) shifting of decarbonization temperature of HEM-activated samples to lower temperature of about 30 °C; (2) decrease in mass losses and temperatures of decomposition with the increasing milling time; and (3) decrease in DTA peak areas for the all HEM-activated samples. As was shown earlier, the HEM treatment has a beneficial effect on the application of the ES. They can be used as: sorbents and soil improvers (separately or as mixtures with apatite minerals or appropriate technogenic wastes, containing main for the plants nutrients—N, P, K, S, Ca et al.).

Processing of Eggshell Biomaterial by Electrical Discharge Assisted Mechanical Milling (EDAMM) and High Energy Milling (HEM) Techniques

In this study, hen eggshell (ES) biomaterial was treated by two mechanochemical methods. Here we show that using of low-current high-voltage electrical impulses during electrical discharge assisted mechanical milling (EDAMM) or high-energy milling (HEM) are proper tools for ES transformation to materials suitable for the further applications. The decomposition of calcite CaCO3 (the main component of ES) into lime CaO (EDAMM treatment) or calcite-aragonite transformation (HEM treatment) were documented by X-ray diffractometry. The applied techniques bring about solid state transformation, high degree of calcite amorphization, and enhancement of specific surface area of ES samples. As examples of using the transformed ES the uptake of cadmium ions during sorption experiments and the dechlorination of polyvinyl chloride are given. In both cases, the technologically accepted recoveries and kinetics have been obtained.