Bead Mill Research Articles

Thin Copper Flakes for Conductive Inks Prepared by Decomposition of Copper Formate and Ultrafine Wet Milling

AbstractFabrication of devices by printing conductive interconnections on plastic substrates is of growing interest. Currently, silver flakes are wildly used, however the high cost of silver prevents their wide use in many electrical devices. A new two‐step process for synthesizing thin copper flakes, and their utilization in conductive inks, is reported. In the first step, sub‐micrometer copper particles are formed by thermal decomposition and self‐reduction of copper formate. These copper particles are then milled in a wet bead mill that results in their transformation into thin flakes with an average thickness of 48 nm. X‐ray diffraction results indicate that the copper particles undergo plastic deformation in a mechanism similar to cold rolling. The effect of various process parameters and type of dispersing agents on the morphology and electrical performance is studied. The ink formulations result in printed patterns with 22% of bulk copper conductivity. The optimal ink is used to print functioning near field communication antennas on polyimide film, which is found to have a high bending durability.

The release of the blue biological pigment C‐phycocyanin through calcium‐aided cytolysis of live Spirulina sp.

C‐phycocyanin is a light‐harvesting phycobiliprotein found in, amongst other species, the cyanobacterium Spirulina sp. C‐phycocyanin is bright blue in colour and can be used as a natural blue colorant for a variety of applications. Various cell disruption methods exist to cause the lysis of the cyanobacterial cells and release of phycocyanin, but these methods have significant drawbacks, such as cost, difficulty in scale‐up, bacterial contamination, or risk of degrading the protein. This article outlines an alternative method for cell disruption based on the use of Ca(II), which lyses live Spirulina biomass, releasing phycocyanin at a range of concentrations (0.1–0.8 m) over varying time periods, depending on the conditions. In comparison with other ionic species tested, Ca(II) performed best by a significant margin. Bead milling of biomass was used to quantify the maximum phycocyanin in the biomass, and the greatest was found to be ca. 90% released into solution after 48 h under 0.5 m Ca(II) in a 0.35 m acetate buffer at pH 6. Exposing Spirulina to sodium azide revealed that the mechanism of Ca(II) ion‐aided cytolysis is likely based on a metabolically driven process. This study demonstrates a potential processing option for the release of phycocyanin from live Spirulina, paving the way for the development of a novel bioprocess for the industrial production of the biological pigment.

Cell wall disruption increases bioavailability of Nannochloropsis gaditana nutrients for juvenile Nile tilapia (Oreochromis niloticus)

In this study the correlation between the accessibility of nutrients and in vivo nutrient digestibility was tested on the marine microalga Nannochloropsis gaditana in juvenile Nile tilapia (Oreochromis niloticus). It was hypothesized that disrupting the cell walls of microalgae increases the nutrient accessibility and digestibility. N. gaditana biomass was subjected to physical treatments (pasteurization, freezing, freeze drying) or mechanical treatments (bead milling) to influence its cell wall integrity. These treatments resulted in an up to 4 x increase in in vitro accessibility of N. gaditana nutrients, assessed from measurements of leaching and susceptibility to protein hydrolysis. Apparent digestibility coefficients of macronutrients, dry matter, energy, phosphorus and calcium of untreated and treated microalgae biomass were determined in triplicate, at a 30% diet inclusion level. Bead milling the algae led to the highest increase in in vivo digestibility of dry matter, energy, protein, fat, ash and calcium on ingredient level, compared to untreated algae biomass. This includes an increase in apparent digestibility coefficient (ADC) of protein and fat from 62 to 78% and from 50 to 82%, respectively. ADCs of total carbohydrates and of phosphorus were not affected by algal cell disruption. In vivo digestibilities of N. gaditana dry matter, energy, protein, and fat were positively correlated (p < .001; r ≥ 0.91) with the nutrient accessibility of N. gaditana, as estimated with in vitro nutrient leaching analyses. This shows that the in vitro methods used are effective ways to assess the effect of mechanical and physical treatments on in vivo nutrient quality of a single ingredient. The results of this study confirm that nutrient accessibility plays a significant role in the nutrient digestibility of the microalga Nannochloropsis gaditana in Nile tilapia.

Design of a transdermal formulation containing raloxifene nanoparticles for osteoporosis treatment.

PurposeIn the clinical setting, raloxifene, a second-generation selective estrogen receptor modulator, is administered orally; however, the bioavailability (BA) is only 2% because of its poor solubility in aqueous fluids and its extensive first-pass metabolism. Therefore, it is expected that the development of a transdermally delivered formulation may reduce the necessary dose without compromising its therapeutic efficacy. In this study, we designed transdermal formulations containing raloxifene nanoparticles and evaluated their usefulness for osteoporosis therapy.MethodsRaloxifene was crushed with methylcellulose by the bead mill method, and the milled raloxifene was gelled with or without menthol (a permeation enhancer) by Carbopol® 934 (without menthol, Ral-NPs; with menthol, mRal-NPs). The drug release and transdermal penetration were measured using a Franz diffusion cell, and the therapeutic evaluation of osteoporosis was determined in an ovariectomized rat model.ResultsThe mean particle size of raloxifene in the transdermal formulation (Ral-NPs) was 173.7 nm. Although the raloxifene released from Ral-NPs remained in the nanoparticle state, the skin penetration of raloxifene nanoparticles was prevented by the stratum corneum in rat. On the other hand, inclusion of menthol in the formulation attenuated the barrier function of the stratum corneum and permitted the penetration of raloxifene nanoparticles through the skin. Moreover, macropinocytosis relates to the skin penetration of the formulation including menthol (mRal-NPs), since penetration was inhibited by treatment with 2 µM rottlerin, a macropinocytosis inhibitor. In addition, the application of 0.3% mRal-NPs (once a day) attenuated the decreases in calcium level and stiffness of the bones of ovariectomized rat.ConclusionWe prepared raloxifene solid nanoparticles by a bead mill method and designed a novel transdermal formulation containing nanoparticles and permeation enhancers. These trans-dermal formulations overcome the barrier properties of the skin and show high drug penetration through the transdermal route (BA 8.5%). In addition, we found that raloxifene transdermal formulations are useful for the treatment of osteoporosis in ovariectomized rat.

Development and Evaluation of a Reconstitutable Dry Suspension to Improve the Dissolution and Oral Absorption of Poorly Water-Soluble Celecoxib.

This study aims at developing and evaluating reconstitutable dry suspension (RDS) improved for dissolution rate, oral absorption, and convenience of use of poorly water-soluble celecoxib (CXB). Micro-sized CXB particle was used to manufacture nanosuspension by using bead milling and then RDS was made by spray-drying the nanosuspension with effective resuspension agent, dextrin. The redispersibility, morphology, particle size, crystallinity, stability, dissolution, and pharmacokinetic profile of the RDS were evaluated. RDS was effectively reconstituted into nanoparticles in 775.8 ± 11.6 nm. It was confirmed that CXB particles are reduced into needle-shape ones in size after the bead-milling process, and the description of CXB was the same in the reconstituted suspension. Through the CXB crystallinity study using differential scanning calorimetry (DSC) and XRD analysis, it was identified that CXB has the CXB active pharmaceutical ingredient (API)’s original crystallinity after the bead milling and spray-drying process. In vitro dissolution of RDS was higher than that of CXB powder (93% versus 28% dissolution at 30 min). Furthermore, RDS formulation resulted in 5.7 and 6.3-fold higher area under the curve (AUC∞) and peak concentration (Cmax) of CXB compared to after oral administration of CXB powder in rats. Collectively, our results suggest that the RDS may be a potential oral dosage formulation for CXB to improve its bioavailability and patient compliance.

Manufacturing process centered on dry-pulp direct kneading method opens a door for commercialization of cellulose nanofiber reinforced composites

We report an integrated production process that simultaneously nanofibrillates dried pulp and uniformly disperses cellulose nanofibers (CNFs) in resins. Refiner-treated pulp were modified using alkenyl succinic anhydride (ASA) in N-Methyl-2-pyrrolidone (NMP). The ASA treated pulp with DS 0, 0.22, 0.43 and 0.57 was mixed with maleic anhydride-grafted polypropylene (MAPP) powder, CaCO3 and high density polyethylene (HDPE) powder (pulp content: 10 wt%). The mixture was melt-extruded at 140 °C with HDPE. The dumbbell-shaped specimens were prepared using injection molding. The SEM images of refiner-treated pulp (DS 0.43) and previously nanofibrillated CNFs (DS 0.44) using a bead mill as a comparison, both of which were extracted from the melt compounded composites, showed comparable degrees of nanofibrillation. The highest mechanical reinforcing efficiency was obtained at DS 0.43, which was shown to exhibit the most fibrillated morphology. The tensile modulus increased from 1.08 GPa for neat HDPE, to 3.46 GPa. The tensile strength also increased from 23 MPa (neat HDPE) to 56 MPa. The mechanical properties were very similar to the bead mill-fibrillated CNF-reinforced composite. This is the first report of nanofibrillation of dried pulp with uniform CNF dispersion into hydrophobic HDPE. We have termed the process the Pulp Direct-Kneading Method.

Preparation of submicron-sized quasi-spherical silica particles via ultrafine grinding with chemical dissolution assistance

Submicron-sized silica particles with the quasi-sphericity were prepared via wet ultrafine grinding in a high energy-density stirred bead mill in the absence and presence of different salt solutions (i.e., water, potassium chloride (KCl), sodium chloride (NaCl), magnesium chloride (MgCl2), calcium chloride (CaCl2), barium chloride (BaCl2) and ammonia chloride (NH4Cl)). Effects of parameters (i.e., salt solution type, salt concentration, solid content of silica particles and grinding time) on the size/size distribution and sphericity of silica particles ground in the mill were investigated. The results show that submicron-sized quasi-spherical silica particles can be obtained under the selected condition (i.e., solution of BaCl2, BaCl2 concentration of 0.01 mol/L, solid content of 20 wt.% and grinding time of 30 min). Besides the size reduction and size distribution improvement, the sphericity can enhance from 0.71 for the original particles to 0.76 for the ground particles in the absence of any salt solution. Also, the proper addition of BaCl2 during ultrafine grinding can give a finer product with a steeper size distribution, and the particle quasi-sphericity increases from 0.76 to 0.89. It is revealed that ultrafine grinding can affect the spheroidization with and without chemical dissolution. In addition, the mechanism for ultrafine grinding of silica particles without and with chemical dissolution assistance was also discussed via the selection and breakage functions from population balance modeling.

Combined effect of attrition and ultrasound on the disruption of Pseudomonas putida for the efficient release of arginine deiminase.

Disruption of Pseudomonas putida KT2440 by ultrasound treatment in a bath sonicator, in presence of the glass beads, was carried out for the release of arginine deiminase (ADI) and the results were compared with that of by Dyno-mill. The release of ADI depended mainly on the bead size and cellmass concentration being disrupted in bead mill. Nearly 23 UmL-1 ADI was released when slurry with a cell-mass concentration of 250 gL-1 was disintegrated for 9 min with 80% bead loading (0.25 mm) in Dyno-mill. Marginally higher amount of ADI (24.1 UmL-1 ) was released by the bath sonication of 250 gL-1 cellmass slurry for 30 min with the beads (0.1 mm) and a sonication power of 170 W. The glass beads, suspended along with the cellmass slurry in bath sonicator, efficiently disrupted the microbial cells to release ADI. Variation in the kinetic constants for the performance parameters implied that ADI release and cell disruption kinetics is a function of disruption technique used and the process variables thereof. Estimation of location factor suggested that selective release of ADI can be achieved. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018 © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:1185-1194, 2018.

Selective and energy efficient extraction of functional proteins from microalgae for food applications

The use of a single controlled bead milling step of the microalga Tetraselmis suecica resulted in a soluble fraction, rich in functional proteins. This was achieved by fine-tuning the processing time, thereby exploiting the difference in rates of protein and carbohydrate release during milling. Soluble proteins were extracted under mild conditions -room temperature, no addition of chemicals, pH 6.5-, with a yield of 22.5% and a specific energy consumption of 0.6 kWh kgDW−1, which is within the recommended minimum energy for an extraction step in a biorefinery process. The resulting protein extract contained 50.4% (DW) of proteins and 26.4% carbohydrates, showed light green color and displayed superior surface activity and gelation behavior compared to whey protein isolate. The proposed process is simple (only one bead milling step), scalable, and allows the mild extraction of functional proteins, making it interesting for industrial applications in the food industry.

In vitro performances and cellular uptake of clarithromycin nanocrystals produced by media milling technique

Nanocrystal technology is one of a promising approach used to improve the solubility of poorly soluble drugs. In this study, media milling technique was used to produce clarithromycin nanocrystals via a bead milling machine. Various sizes of clarithromycin nanocrystals (250 nm–1 μm) were prepared using different milling times. The polymorphism and crystallinity of nanocrystals were characterized by powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC) techniques. The results indicated no polymorphic change after the milling process. However, the crystallinity of the obtained nanocrystals slightly decreased upon the milling time. The kinetic saturation solubility of all sizes of the clarithromycin nanocrystals was found to reach a maximum solubility or the supersaturation within an hour in HBSS buffers pH 6.8 and 5.0. The maximum solubility of the smaller nanocrystals was higher than that of the larger ones. In addition, the dissolution rate of the nanocrystals was enhanced after the particle size reduction. Permeability and cellular uptake of the clarithromycin nanocrystals were observed in Caco-2 and NCI-N87 cells. No significant difference in drug permeation of the different size nanocrystals was observed in NCI-N87 cell monolayer due to the high solubility of clarithromycin in an acidic environment. However, the drug transport, the apparent permeability coefficient (Papp) and the drug internalization in Caco-2 cell monolayer were found to increase when the particle size of clarithromycin was reduced to the nanosized range. Based on the results, the particle size strongly influenced the saturation solubility, dissolution rate, in vitro drug permeation and internalization of clarithromycin nanocrystals.

Involvement of Endocytosis in the Transdermal Penetration Mechanism of Ketoprofen Nanoparticles.

We previously designed a novel transdermal formulation containing ketoprofen solid nanoparticles (KET-NPs formulation), and showed that the skin penetration from the KET-NPs formulation was higher than that of a transdermal formulation containing ketoprofen microparticles (KET-MPs formulation). However, the precise mechanism for the skin penetration from the KET-NPs formulation was not clear. In this study we investigated whether energy-dependent endocytosis relates to the transdermal delivery from a 1.5% KET-NPs formulation. Transdermal formulations were prepared by a bead mill method using additives including methylcellulose and carbopol 934. The mean particle size of the ketoprofen nanoparticles was 98.3 nm. Four inhibitors of endocytosis dissolved in 0.5% DMSO (54 μM nystatin, a caveolae-mediated endocytosis inhibitor; 40 μM dynasore, a clathrin-mediated endocytosis inhibitor; 2 μM rottlerin, a macropinocytosis inhibitor; 10 μM cytochalasin D, a phagocytosis inhibitor) were used in this study. In the transdermal penetration study using a Franz diffusion cell, skin penetration through rat skin treated with cytochalasin D was similar to the control (DMSO) group. In contrast to the results for cytochalasin D, skin penetration from the KET-NPs formulation was significantly decreased by treatment with nystatin, dynasore or rottlerin with penetrated ketoprofen concentration-time curves (AUC) values 65%, 69% and 73% of control, respectively. Furthermore, multi-treatment with all three inhibitors (nystatin, dynasore and rottlerin) strongly suppressed the skin penetration from the KET-NPs formulation with an AUC value 13.4% that of the control. In conclusion, we found that caveolae-mediated endocytosis, clathrin-mediated endocytosis and macropinocytosis are all related to the skin penetration from the KET-NPs formulation. These findings provide significant information for the design of nanomedicines in transdermal formulations.

Bead milling disruption kinetics of microalgae: Process modeling, optimization and application to biomolecules recovery from Chlorella sorokiniana

Industrial development of microalgae biomass valorization relies on process optimization and controlled scale-up. Both need robust modeling: (i) for biomass production and (ii) for integrated processes in the downstream processing (DSP). Cell disruption and primary fractionation are key steps in DSP. In this study, a kinetic model, including microalgal cell size distribution, was developed for Chlorella sorokiniana disruption in continuous bead milling. Glass beads of 0.4 mm size at impeller tip velocity of 14 m.s−1 were used as optimal conditions for efficient cell disruption. These conditions allowed faster disruption of big cells than small ones. A modified expression of the Stress Number, including cell size effect, was then proposed and validated.Separation of starch, proteins and chlorophyll by mild centrifugation was studied as function of the disruption parameters. Low energy consumption conditions led to extreme comminution. An intermediate zone drew attention for allowing moderate energy consumption and efficient metabolites separation by centrifugation.

Techno-Functional Properties of Crude Extracts from the Green Microalga Tetraselmis suecica.

A mild fractionation process to extract functional biomolecules from green microalgae was implemented. The process includes bead milling, centrifugation, and filtration with several membrane cut-offs. For each fraction, the corresponding composition was measured, and the surface activity and gelation behavior were determined. A maximum protein yield of 12% was obtained in the supernatant after bead milling and between 3.2 and 11.7% after filtration. Compared to whey protein isolate, most of the algae fractions exhibited comparable or enhanced functionality. Surface activity for air–water and oil–water interfaces and gelation activities were notably superior for the retentate fractions compared to the permeates. It is proposed that such functionality in the retentates is due to the presence of hydrophobic compounds and molecular complexes exhibiting a similar behavior as Pickering particles. We demonstrated that excellent functionality can be obtained with crude fractions, requiring minimum processing and, thus, constituting an interesting option for commercial applications.

Microalgae disruption techniques for product recovery: influence of cell wall composition

Microalgae are one of the most promising feedstocks for the production of commodity and value-added products. However, the use of microalgae as a feedstock is hampered by the process economics and sustainability. Overall sustainability can be improved by employing energy-efficient cell disruption and recovery processes to maximize the extraction of desired compounds from microalgal biomass. Most often, extraction processes are conducted with solvents using untreated, chemically treated, or mechanically treated cells. However, microalgal cell walls are sometimes structurally robust, complex, and chemically diverse and high energy inputs or large quantities of chemicals are required to extract products from within the cell. Various chemical, biological, and physical techniques have been employed to disrupt the cell walls from a variety of microalgae species, and these include the use of surfactants, autoclave, microwave, sonication, bead milling, enzymatic hydrolysis, high-pressure homogenization, and steam treatments. Although the cell wall structure is important for product recovery, it is often not considered when selecting the most appropriate disruption method. In this study, the cell wall structure of selected microalgae species and the effectiveness of various cell wall disruption techniques on product recovery are reviewed. It was concluded that future research must focus on developing an understanding of the relationship between cell wall disruption mechanisms and cell wall composition and structure, as well as optimizing the energy consumption of the disruption technique. This approach would enable the design of innovative cell wall disruption techniques for an enhanced product recovery.

Novel bead-milling mechanically pulverized bulk mineral particles to ultrafine scale: Energy storage and cleaner promotion of mineral extraction

Abstract Novel bead-milling (BM), comprising of rough- and fine-milling processes, was developed and adopted to mechanically pulverize natural carbonate manganese (MnC) and zinc oxide (ZnO). Real-time trackings showed that bulk mineral particles were finally pulverized to ultrafine scale (Z-avg hydrodynamic diameter ∼244 nm for MnC, ∼178 nm for ZnO), implying excellent activation potential of BM. Meanwhile, tracking results strongly indicated that BM process was in the feature of initial coexisting mineral dissociation and subsequent mechanico-chemical reaction, even phase transformation. Besides initiating the decrease of mineral particle size (also the increase of surface area), fierce mechanico-chemical reaction caused the dislocation and edge/corner generation, crystalline structure destruction, which were among the effective approaches for defect formation. Note that all these processes were inherently interrelated and contributed to the energy storage of activated mineral, which was verified by the TG/FTIR characterization. The stored energy would make up for the energy required to break the lattice constraint by acidic extraction. Consistently, it was found that BM evidently promoted the Mn extraction efficiency from 46.5% to 74.8% and additional ligand complexation further promoted the extraction efficiency by another ∼10%. As a result, less acid was consumed and accordingly less acidic wastes was discharged. This investigation might be enlightening for adopting proper strategies to promote the mineral extraction in a cleaner way.

An Overview of Current Pretreatment Methods Used to Improve Lipid Extraction from Oleaginous Micro-Organisms.

Microbial oils, obtained from oleaginous microorganisms are an emerging source of commercially valuable chemicals ranging from pharmaceuticals to the petroleum industry. In petroleum biorefineries, the microbial biomass has become a sustainable source of renewable biofuels. Biodiesel is mainly produced from oils obtained from oleaginous microorganisms involving various upstream and downstream processes, such as cultivation, harvesting, lipid extraction, and transesterification. Among them, lipid extraction is a crucial step for the process and it represents an important bottleneck for the commercial scale production of biodiesel. Lipids are synthesized in the cellular compartment of oleaginous microorganisms in the form of lipid droplets, so it is necessary to disrupt the cells prior to lipid extraction in order to improve the extraction yields. Various mechanical, chemical and physicochemical pretreatment methods are employed to disintegrate the cellular membrane of oleaginous microorganisms. The objective of the present review article is to evaluate the various pretreatment methods for efficient lipid extraction from the oleaginous cellular biomass available to date, as well as to discuss their advantages and disadvantages, including their effect on the lipid yield. The discussed mechanical pretreatment methods are oil expeller, bead milling, ultrasonication, microwave, high-speed and high-pressure homogenizer, laser, autoclaving, pulsed electric field, and non-mechanical methods, such as enzymatic treatment, including various emerging cell disruption techniques.

Comparative analysis of equipment and research the superfine grinding process of titanium dioxide and quinacridone red suspensions in the bead mill

Comparative analysis of equipment and research the superfine grinding process of titanium dioxide and quinacridone red suspensions in the bead mill

Is it time for routinely tracking of early immunosuppression in tracking and prognosing patients with acute pancreatitis?

(Ni, Sb)-co-doped rutile yellow ceramic pigments were synthesized via a mechanical activation-assisted solid-state reaction in a stirred bead mill. The effects of mechanical grinding of the raw materials on the synthesis of (Ni, Sb)-co-doped rutile pigment were investigated. The results show that mechanical activation effectively decreased the crystallinity of the mixed precursors, thus enhancing their reactivity and the migration rate of ions. These effects lowered the temperature required for formation of the rutile phase. Compared with results from a mixture of separately ground precursors, the mixture of raw materials ground together was more effective for accelerating nickel/antimony ions doping into the TiO2 structure and improved the color performance of the pigment. The pigment from the mixed raw materials ground for 2.0 h and heat-treated at 1100 °C could be used as an environmentally-friendly ceramic yellow pigment owing to its low-toxicity, bright yellow hue, good chemical/thermal durability, and high cost-effectiveness.

Synthesis and characterization of (Ni, Sb)-co-doped rutile ceramic pigment via mechanical activation-assisted solid-state reaction

(Ni, Sb)-co-doped rutile yellow ceramic pigments were synthesized via a mechanical activation-assisted solid-state reaction in a stirred bead mill. The effects of mechanical grinding of the raw materials on the synthesis of (Ni, Sb)-co-doped rutile pigment were investigated. The results show that mechanical activation effectively decreased the crystallinity of the mixed precursors, thus enhancing their reactivity and the migration rate of ions. These effects lowered the temperature required for formation of the rutile phase. Compared with results from a mixture of separately ground precursors, the mixture of raw materials ground together was more effective for accelerating nickel/antimony ions doping into the TiO2 structure and improved the color performance of the pigment. The pigment from the mixed raw materials ground for 2.0h and heat-treated at 1100°C could be used as an environmentally-friendly ceramic yellow pigment owing to its low-toxicity, bright yellow hue, good chemical/thermal durability, and high cost-effectiveness.

Synergistic effect between ultrasound and fierce mechanical activation towards mineral extraction: A case study of ZnO ore

Though the positive role of ultrasound has been confirmed in the mineral extraction, its potential towards fiercely mechanically-activated mineral was not yet mentioned. In this study, as a novel mechanical activation style, bead milling (BM) was presented and ZnO ore was selected to determine its effectiveness. Results showed that median particle size of ZnO ore could be pulverized to as low as 1/164 of its original value (from ∼29.2 μm to ∼178 nm), indicating much higher activation potential of BM than that of conventional ball milling. Besides, structure destruction, even phase transformation with the direct participation of airborne CO2 occurred. All these processes rendered the superior activation capacity of BM. In view of the extraction promotion, the combination of ultrasound and BM exerted more pronounced effect than those of individual ones, indicating the synergistic effect between extra energy input (by ultrasound) and inner energy storage (by fierce BM). The classic shrinking core model with the product layer diffusion as the rate-controlling step was found to well model the extraction kinetics. The modeling disclosed high capability of ultrasound and BM combination in decreasing the activation energy (Ea) (from 54.6 kJ/mol to 26.4 kJ/mol), while ultrasound, BM could only decrease the Ea to 44.9 kJ/mol, 41.5 kJ/mol, respectively. The dual roles of ultrasound were specially highlighted: (i) participation in the extraction process via direct energy input, (ii) regulation of the aggregation that the activated ore suspension was confronted with.