Bubble Stability Research Articles

Pengaruh Fraksi Berat Serbuk Alumina Terhadap Porositas Busa Aluminium Hasil Injeksi Gas

Aluminum foam is a very interesting material to develop. This material is a material that has a combination of characteristics between physical and mechanical properties such as high stiffness and low density. There are several processes for making aluminum foam that have been developed, either through the liquid, solid, or gas phases. And of these various processes, the process of making aluminum foam through the liquid phase by using the gas injection method is the simplest and cheapest process. The principle of the process of making aluminum foam with this method is that bubbles are produced from the process of blowing the gas into the aluminum liquid in which there are additive particles that function as a bubble stabilizer. These stable bubbles will become pores after the aluminum liquid solidifies. This research will discuss the effect of the weight fraction of alumina powder with an average size of 5.77 μm added to liquid aluminum on the macro-pore structure in the form of shape and size as well as the spread of the resulting pores. And the result is that the optimal weight fraction of adding alumina powder is 15%, where the resulting pores have a more homogeneous and evenly shaped and sized.

An investigation on the bubble transportation of a two-stage series venturi bubble generator

In this paper, we designed a new venturi bubble generator, which mainly consist of two serial rectangular perspex venturi channels with the same geometrical dimension. Visualization experimental method combined with digital image analysis was adopted to study the motion, deformation and breakup process of bubbles when the micro-bubble generator was installed vertically. The bubble foaming frequency which is defined as the amount of forming bubbles within one second from the air injection hole was significantly enhanced with the increase of water flow rate, but was not sensitively affected by the air flow rate. The discrete bubbles moved in a two-stage venturi channel and experienced collapse or breakup in the divergent section. The Sauter mean diameter of bubbles which recorded in each divergent outlet decreased gradually. The Reynolds numbers of water had a significant effect on the breakup characteristics of bubbles. With the increasing of Re, the bubbles experienced binary breakage and multiple breakup successively. Under the effect of complex turbulence vortex, the bubbles presented different breakup patterns in each stage. When Reth>19793, the bubble breakup ratio of the first stage divergent section was larger than that of the second stage, and the difference of the generated bubble Sauter mean diameter in each divergent outlet was minimized accordingly. The surface stability of the daughter bubble was enhanced, and it was difficult to breakup significantly under the effect of recirculation flow. The numerical simulation results by Computational Fluid Dynamics (CFD) indicated that the area of the vortex was increased for larger second stage divergent angle, which intensify the phase interaction and promote the possibility of sub-micron bubble breakup.

Trapping stable bubbles in hydrophobic microchannel for continuous ultrasonic microparticle manipulation

The application of bubbles in lab-on-chip devices has attracted considerable attention and is exerting an increasingly significant role in recent years due to its influential functions for fluid and particle manipulation. Herein, we demonstrated a simple air bubble trapping method based on the surface tension of hydrophobic chip material and demonstrated particle manipulation utilizing oscillating bubbles. The microfluidic device has a T-shaped junction structure with triangular obstacles, which allows us to transfer air-pocket generated due to non-synchronized liquid filling in the microchannel to stable bubbles attached to channel wall at the desired location. The trapped bubbles can maintain stable state at a flow rate of less than 50 μL/min. By activating bubbles with the sound wave at a specific frequency, we can achieve particle focusing, trapping, extraction and enrichment in a contact-free, label-free and continuous manner. The proposed bubble trapping method may serve as a reusable, detachable and biocompatible tool for broader bubble-based applications in chemical, biology, and engineering fields, such as drug delivery, cell focusing, as well as isolation of tumor cell.

Hydrodynamic interaction and coalescence of two inline bubbles rising in a viscoelastic liquid

In this paper, direct numerical simulations (DNS) are performed to investigate the inline rise of a pair of three-dimensional (3D) air bubbles in a viscoelastic liquid using the volume-of-fluid approach with an adaptive mesh refinement technique. The exponential Phan-Thien–Tanner model is used as the non-linear viscoelastic constitutive equation for the liquid. The numerical model has been validated by comparison with previously published results, including the terminal velocity jump discontinuity of an isolated bubble rising in a viscoelastic fluid, when its volume exceeds a certain critical value. Focusing on the inline rising bubble pair in such a viscoelastic medium with different configurations, we found that the wake of the small leading bubble attracts a larger trailing bubble, whereas for a supercritical bubble in front of a subcritical bubble, they tend to further separate. Before reaching a critical volume, the two subcritical bubbles remain close to each other after approaching each other, forming a stable chain. For pairs containing a supercritical trailing bubble, however, a drafting–kissing scenario occurs before the bubble–bubble coalescence. The long-range repulsion and the short-range attraction due to fluid elasticity are critical to the aforementioned bubble pair interactions. Interestingly, the terminal rise velocities of the stable bubble chain and the coalesced bubble both increase with the initial spacing. The squeezing flow near the growing bubble neck seems to delay the coalescence process. The capillary wave propagating down to the coalesced bubble tip together with the extensional flow behind the stretched bubble determines the generation of satellite microdroplets along the tail of the coalesced bubble. To the best of our knowledge, this is the first 3D DNS on a bubble pair ascending in viscoelastic fluids.

Direct observation of topological charge impacting skyrmion bubble stability in Pt/Ni/Co asymmetric superlattices

We characterize the magnetic properties and domain structure of Pt/Ni/Co asymmetric superlattices in comparison to the more established Pt/Co/Ni structure. This reversal in stacking sequence leads to a marked drop in interfacial magnetic anisotropy and the magnitude of the interfacial Dzyaloshinskii–Moriya interaction as inferred from the domain wall (DW) structure, which we speculate could be related to a degradation of the Pt/Co interface when Pt is deposited on top of the Co layer. Lorentz transmission electron microscopy exclusively reveals Néel-type DWs and, with a perpendicular field, Néel skyrmions in the Pt/Co/Ni films. Conversely, the Pt/Ni/Co samples show only achiral Bloch DWs, which leads to the formation of achiral Bloch and type II bubbles at an increased perpendicular field. Combined with the reduced anisotropy leading to greater bubble densities, the latter case makes for an excellent test bed to examine the benefits of topological charge on stability. Simultaneous observation of Bloch and type II bubbles shows a roughly 50 mT larger annihilation field for the former. An in-plane component to the magnetic field is shown to both impact the structure of the formed bubbles and separately suppress the topological benefit.

GPU accelerated numerical investigation of the spherical stability of an acoustic cavitation bubble excited by dual-frequency

The spherical stability of an acoustic cavitation bubble under dual-frequency excitation is investigated numerically. The radial dynamics is described by the Keller–Miksis equation, which is a second-order ordinary differential equation. The surface dynamics is modelled by a set of linear ordinary differential equation according to Hao and Prosperetti (1999), which takes into account the effect of vorticity by boundary layer approximation. Due to the large amount of investigated parameter combinations, the numerical computations were carried out on graphics processing units. The results showed that for bubble size between RE=2μm and 4μm, the combination of a low and a high frequency, and the combination of two close but not equal frequencies are important to prevent the bubble losing its shape stability, while reaching the chemical threshold (Rmax/RE=3) (Kalmár et al., 2020). The phase shift between harmonic components of dual-frequency excitation has no effect on the shape stability.

Probing the interactions between air bubbles and (bio)interfaces at the nanoscale using FluidFM technology

Understanding the molecular mechanisms underlying bubble-(bio)surfaces interactions is currently a challenge that if overcame, would allow to understand and control the various processes in which they are involved. Atomic force microscopy is a useful technique to measure such interactions, but it is limited by the large size and instability of the bubbles that it can use, attached either on cantilevers or on surfaces. We here present new developments where microsized and stable bubbles are produced using FluidFM technology, which combines AFM and microfluidics. The air bubbles produced were used to probe the interactions with hydrophobic samples, showing that bubbles in water behave like hydrophobic surfaces. They thus could be used to measure the hydrophobic properties of microorganisms’ surfaces, but in this case the interactions are also influenced by electrostatic forces. Finally a strategy was developed to functionalize their surface, thereby modulating their interactions with microorganism interfaces. This new method provides a valuable tool to understand bubble-(bio)surfaces interactions but also to engineer them.

Effect of Low Atmospheric Pressure on Bubble Stability of Air-Entrained Concrete

The effect of low atmospheric pressure of the environment on the air content and bubble stability of air-entrained concrete was investigated in Beijing and Lhasa. The results indicate that the reduction of atmospheric pressure can weaken the air-entraining capability of air-entraining agents (AEAs). The air content of fresh concrete decreased by 9%–39% when the atmospheric pressure dropped to 64 kPa. The bubble stability of concrete mixed at a low atmospheric pressure becomes worse. Within 50–55 min after mixing, the air content of concrete mixed at a low atmospheric pressure decreases greatly, and the void spacing factor increases obviously. The concrete mixed at a low atmospheric pressure will lose more air content when vibration time increases, leading to the decrease of air content and the increase of the spacing factor, which are more significant than the concrete mixed at normal atmospheric pressure. On the basis of the experiment results in this study, the type of AEAs must be carefully selected, and the vibration time must be strictly controlled to ensure that the air content of concrete will meet the design requirements in low atmospheric pressure areas.

Stabilization and topological transformation of magnetic bubbles in disks of a kagome magnet

Magnetic bubbles are cylinder domains found in a wide variety of uniaxial ferromagnets. They are categorized into two types based on the rotational sense of their domain walls. These two types of bubbles have the potential to be binary states in a skyrmion-bubble-based magnetic memory. Experimental realization of a single bubble along with single bubble transformations in nanostructures is important for single bit operations in such a memory but has not yet been demonstrated. In this study, effects of geometrical confinement on stabilization and transformation of magnetic bubbles in Fe3Sn2 disks were explored. We observed magnetic bubble cluster states with a tunable bubble number based on the disk size and tilted field angle. By tracking the size dependence of the bubble number, we further demonstrate how both types of single bubbles can be realized and transformed into each other in a controlled manner without bubble number variation.

Synthesis of polytriethanolamine based surfactant and its flotation performance evaluation of oilfield produced water treatment

As the amount of oilfield produced water (PW) keeps going up, highly efficient flotation agent is needed. In this paper, a series of surfactants (abbreviated as Q-PTEA-Cn) derived from polytriethanolamine were synthesized. Their surface activities and flotation performance were evaluated. The result showed that the Q-PTEA-Cns can effectively reduce the surface tension of water and interface tension of crude oil/water. The Q-PTEA-C12-1 had the best flotation performance and the rational flotation condition was recommended as follows: Q-PTEA-C12-1 dosage 100 mg/L, gas flow 3 L/min, and flotation time 20 minutes. At this condition, the oil removal efficiency of two commonly used flotation agents (FL-1 and FL-2) and Q-PTEA-C12-1 were 62.3%, 69.1%, and 83.6%, respectively. The flotation kinetic of Q-PTEA-C12-1 can be described by Maruyama’s flotation model, which presented that there was adsorption of oil droplet adsorbed surfactant onto bubble. Floatation mechanism study confirmed that the Q-PTEA-C12-1 can absorb onto the oil droplet and showed that the Q-PTEA-C12-1 can enhance the bubble–drop attachment efficiency and the stability of bubble–drop agglomerates.

Gastrointestinal Distension by Pectin-Containing Carbonated Solution Suppresses Food Intake and Enhances Glucose Tolerance via GLP-1 Secretion and Vagal Afferent Activation.

Diet-induced gastrointestinal distension is known to evoke satiation and suppress postprandial hyperglycemia; however, the underlying mechanisms remain poorly understood. This study explored how gastrointestinal distension regulates energy homeostasis by using inflating stomach formulation (ISF), the carbonated solution containing pectin that forms stable gel bubbles under acidic condition in the stomach. Here we show that, in mice, oral administration of ISF induced distension of stomach and proximal intestine temporarily, stimulated intestinal glucagon-like peptide-1 (GLP-1) secretion, and activated vagal afferents and brainstem. ISF suppressed food intake and improved glucose tolerance via enhancing insulin sensitivity. The anorexigenic effect was partially inhibited, and the beneficial glycemic effect was blunted by pharmacological GLP-1 receptor blockade and chemical denervation of capsaicin-sensitive sensory nerves. In HFD-fed obese mice showing arrhythmic feeding and obesity, subchronic ISF treatment at the light period (LP) onset for 10 days attenuated LP hyperphagia and visceral fat accumulation. These results demonstrate that gastrointestinal distension by ISF stimulates GLP-1 secretion and the vagal afferent signaling to the brain, thereby regulating feeding behavior and glucose tolerance. Furthermore, subchronic ISF treatment ameliorates HFD-induced visceral obesity. We propose the diet that induces gastrointestinal distension as a novel treatment of hyperphagic obesity and diabetes.

Effects of dynamic adsorption on bubble formation and coalescence in partitioned-EDGE devices

HypothesisDynamic adsorption effects can play a crucial role in bubble formation and stabilization. We hypothesize that microfluidic tools provide direct insights to these effects, and that the final bubble size depends on the intersection of time scales for bubble formation versus adsorption of proteins. ExperimentsWe use a microfluidic device to study Laplace pressure-driven formation of bubbles that are stabilized by whey proteins. Bubble behavior is studied as a function of the pressure difference imposed across the pores (Pd∗), and thus the bubble formation time (τ, ranging from μs to s), using highspeed recordings, quasi-static pressure arguments and a semi-empirical coalescence model. FindingsWe observe two distinct bubble formation regimes, delimited by the pressure difference required to initiate bubble formation in pure water, Pd∗= 1400 mbar. When Pd∗<1400 mbar, protein adsorption is a requisite to lower the surface tension and initialize bubble formation. Individual bubbles (fixed d0~ 25 μm) are formed slowly with τ≫1 ms. When Pd∗ exceeds 1400 mbar, bubbles (fixed d0~ 16 μm) experience no adsorption lag and thus are formed at steeply increasing frequency, with τ < 1 ms. Interaction between these bubbles causes finite coalescence to a diameter dcoal that increases for lower τ. A minimum time of 0.4 ms is needed to immediately stabilize individual bubbles. Our study provides a promising microfluidic tool to study bubble formation and coalescence dynamics simultaneously.

Morphology development of PLAs with different stereo-regularities in ternary blend PBSA/PBS/PLA films

ABSTRACT This study was to investigate the influence of incorporating poly(lactic acid) (PLA) with different stereo-regularities into poly(butylene succinate-co-adipate) (PBSA)/poly(butylene succinate) (PBS). The PBSA/PBS matrix phase was fixed at 70/30 wt%, whereas the PLA contents were varied from 10 to 30 wt%. Two grades of PLAs with different D-lactide contents of 4.0% (Hi-PLA) and 1.0% (Lo-PLA) were used. The developed microstructures and morphologies of dispersed PLA phases were purposed from DSC and WAXD studies. Basically, the presence of PLAs in ternary blends significantly enhanced the bubble stability during film blowing. According to the different chain backbones of PLA, Hi-PLA was completely melted during the extrusion process and coalescence led to a larger size of the dispersed phase. The biaxial deformation of dispersed Hi-PLA occurred in bubble inflation stages bringing to the layer-like morphology. Conversely, the cold crystallization occurred in Lo-PLA droplets which could not further deform during the bubble forming. The different reinforcing morphologies of these PLA minor phases were investigated and correlated with their mechanical properties of ternary blend films. A good balance of stiffness and toughness was achieved from ternary blend containing 10 wt% of Hi-PLA. Finally, the developed PBSA/PBS/PLA films can be suggested as a suitable packaging for environmental sustainability.

Polysaccharide-stabilized aqueous foams to fabricate highly oil-absorbing cryogels: Application and formation process for preparation of edible oleogels

The application of biopolymers in soft edible materials has been gaining particular concerns, especially the replacement of saturated fats. This work presented a lightweight and highly oil-absorbing cryogel fabricated by two polysaccharides (hydroxypropyl methylcellulose (HPMC) and xanthan gum (XG)) via the foam-templated method to prepare oleogels with low-saturated oils. The cryogel was freeze-dried from HPMC and XG co-stabilized aqueous foams, in which the polysaccharide-based network was established. The thickening effect of XG dramatically improved the bubble stability, which avoided the bubble collapse during cryogelation and greatly heightened the oil absorption capacity of cryogels. Cryogels had a porosity >97% and could absorb 72 times their weight of oils at the HPMC concentration of 0.8 wt%. Increased HPMC diminished pores of cryogels, hardening the cryogel and generating a greater capillary force for preparing viscoelasticity-enhanced oleogels. The temperature-stable oleogel was endowed with a better structural recovery ability from adding XG. Absorption kinetic models showed that irregular pores in cryogels had similar sizes. Polysaccharides are promising materials to create porous bio-functional cryogels and construct low saturated oleogels, facilitating oleogels to substitute saturated fats.

Noble gas bubbles in bcc metals: Ab initio-based theory and kinetic Monte Carlo modeling

Understanding the interactions of noble gases with metals is of fundamental importance for the design of radiation-resistant structural materials for fission and fusion nuclear reactors. Here we present a unified theory for describing the energetics of He, Ne, Ar, and Kr bubbles in bcc metals in group 5B (V, Nb, Ta), 6B (Cr, Mo, W) and 8B (Fe). Our predictive analytical model is based on the effective-medium and isotropic elasticity theories, and is parameterized using density functional theory (DFT) calculations of small gas-vacancy clusters. By performing kinetic Monte Carlo (KMC) simulations driven by our analytical model, we have predicted the lifetimes of noble gas bubbles and their coarsening by Ostwald ripening. Our most notable finding is the exceptionally higher thermal stability of Ne, Ar and Kr bubbles than He bubbles in bcc metals, conferring them outstanding resistance to Ostwald ripening. The physical origin of the unexpected stability of bubbles formed by large noble gas atoms has been further elucidated. Our theoretical finding is consistent with the experimental observation of He gas bubble superlattice (GBS) coarsening under thermal annealing, and provides new insights on the exceptional stability of fission GBS in bcc U-Mo up to a high homologous temperature of 0.78. The present calculated results also compare favorably with the existing thermal helium desorption spectrometry experiments in the literature.

Spatially-directed angiogenesis using ultrasound-controlled release of basic fibroblast growth factor from acoustically-responsive scaffolds

Vascularization is a critical step following implantation of an engineered tissue construct in order to maintain its viability. The ability to spatially pattern or direct vascularization could be therapeutically beneficial for anastomosis and vessel in-growth. However, acellular and cell-based strategies to stimulate vascularization typically do not afford this control. We have developed an ultrasound-based method of spatially- controlling regenerative processes using acellular, composite hydrogels termed acoustically-responsive scaffolds (ARSs). An ARS consists of a fibrin matrix doped with a phase-shift double emulsion (PSDE). A therapeutic payload, which is initially contained within the PSDE, is released by an ultrasound-mediated process called acoustic droplet vaporization (ADV). During ADV, the perfluorocarbon (PFC) phase within the PSDE is vaporized into a gas bubble. In this study, we generated ex situ four different spatial patterns of ADV within ARSs containing basic fibroblast growth factor (bFGF), which were subcutaneously implanted in mice. The PFC species within the PSDE significantly affected the morphology of the ARS, based on the stability of the gas bubble generated by ADV, which impacted host cell migration. Irrespective of PFC, significantly greater cell proliferation (i.e., up to 2.9-fold) and angiogenesis (i.e., up to 3.7-fold) were observed adjacent to +ADV regions of the ARSs compared to -ADV regions. The morphology of the PSDE, macrophage infiltration, and perfusion in the implant region were also quantified. These results demonstrate that spatially-defined patterns of ADV within an ARS can elicit spatially-defined patterns of angiogenesis. Overall, these finding can be applied to improve strategies for spatially-controlling vascularization. Statement of significanceVascularization is a critical step following implantation of an engineered tissue. The ability to spatially pattern or direct vascularization could be therapeutically beneficial for inosculation and vessel in-growth. However, acellular and cell-based strategies to stimulate vascularization typically do not afford this control. We have developed an ultrasound-based method of spatially-controlling angiogenesis using acellular, composite hydrogels termed acoustically-responsive scaffolds (ARSs). An ARS consists of a fibrin matrix doped with a phase-shift double emulsion (PSDE). An ultrasound-mediated process called acoustic droplet vaporization (ADV) was used to release basic fibroblast growth factor (bFGF), which was initially contained within the PSDE. We demonstrate that spatially-defined patterns of ADV within an ARS can elicit spatially-defined patterns of angiogenesis in vivo. Overall, these finding can improve strategies for spatially-controlling vascularization.

Effect of sodium hydroxide solution concentration on liquid entrainment in a steam boiler

Liquid entrainment or carryover is a phenomenon that liquid droplets are carried out from a boiler or steam drum during steam generation. The droplets may convey some dissolved solids and cause damage to steam equipment such as scaling deposits in valves and steam piping and erosion of turbine blades. The appearance of dissolved solids in boiler water mainly comes from the internal water treatment process by dosing some chemical substances into the boiler in order to prevent corrosion and scale formation. Trisodium phosphate (Na3PO4) is one of chemical substances commonly added during boiler operation to control the pH of boiler water. However, it can cause the occurrence of sodium hydroxide (NaOH) solution which results in the increase of total dissolved solid (TDS) concentration in boiler water. Therefore, this study is aimed to develop a test section in order to investigate the parameters affected by liquid entrainment in the boiler. The experiment is performed in ambient conditions under an air-water system. Three variable factors are taken into consideration, including the concentration of NaOH solution, the height of the water level in the test tank, and the gas superficial velocity which represents the flow velocity of steam during steam generation. The results show that the increase of the gas superficial velocity and the water level height in the tank resulted in the enhancement of the entrainment rate. The increase of the water level height played an important role on the liquid entrainment. The increase of NaOH concentration directly impacted the existing film bubbles and the longer stability of foam bubbles at the water surface which resulted in a higher entrainment rate. Therefore, TDS control was one of the most important factors which could be incorporated with the appropriate height of the water level and the consistency rate of steam generation in order to minimize the liquid entrainment.

Effects of anti-clay agents on bubble size distribution and stability of aqueous foam under pressure for earth pressure balance shield tunneling

The earth pressure balance (EPB) shield inevitably encounters heavy clay soils during tunneling, which form mud cakes on the cutter head. To prevent this, it is necessary to add anti-clay agents to foam agents. However, the effect of anti-clay agents on foam properties and its optimal concentration under different conditions remain unknown. In this study, the bubble size distribution and half-life of foam produced by foam agents and anti-clay agents under pressure were measured and analyzed. The results show that the mean bubble radius decreases with the addition of anti-clay agents at 0 bar but increases at a pressure of 1 bar or 2 bar. The anti-clay agents weaken the stability of foam, and optimal concentrations of anti-clay agents for different test pressures are proposed. The test results obtained provided guidance for selection of the optimal concentration of anti-clay agents to be used in EPB shield tunneling.

The performance of ultra-lightweight foamed concrete incorporating nanosilica

This paper aims to investigate the feasibility of the incorporation of nanosilica (NS) in ultra-lightweight foamed concrete (ULFC), with an oven-dry density of 350 kg/m3, in regard to its fresh and hardened characteristics. The performance of various dosages of NS, up to 10 wt.-%, were examined. In addition, fly ash and silica fume were used as cement replacing materials, to compare their influence on the properties of foamed concrete. Mechanical and physical properties, drying shrinkage and the sorption of concrete were measured. Scanning electron microscopy (SEM) and X-ray microcomputed tomography (µ-CT) and a probabilistic approach were implemented to evaluate the microstructural changes associated with the incorporation of different additives, such as wall thickness and pore anisotropy of produced ULFCs. The experimental results confirmed that the use of NS in optimal dosage is an effective way to improve the stability of foam bubbles in the fresh state. Incorporation of NS decrease the pore anisotropy and allows to produce a foamed concrete with increased wall thickness. As a result more robust and homogenous microstructure is produced which translate to improved mechanical and transport related properties. It was found that replacement of cement with 5 wt.-% and 10 wt.-% NS increase the compressive strength of ULFC by 20% and 25%, respectively, when compared to control concrete. The drying shrinkage of the NS-incorporated mixes was higher than in the control mix at early ages, while decreasing at 28 d. In overall, it was found that NS is more effective than other conventional fine materials in improving the stability of fresh mixture as well as enhancing the strength of foamed concrete and reducing its porosity and sorption.

Characterization of the Chemical and Physical Properties of Bar Soap Made with Different Concentrations of Bentonite as a Filler

The use of bentonite in cosmetics is considered beneficial for absorbing dirt and moisturizing and detoxifying the skin. In this study, different amounts of bentonite (10, 12.5, 15, 17.5, and 20 g) were used as a filler in 5 separate formulations of natural bar soap having coconut oil as the primary ingredient. Each type of bentonite soap was analyzed in accordance with the Indonesian National Standards (SNI). The free alkali content for each of the five preparations of bentonite soap was zero, the moisture content ranged from 0.88 to 1.15 %, the pH ranged from 8.7 to 8.8, the total free fatty acid content ranged from 0.28 to 0.72, and the foam or bubble stability was above 70%, while the soap’s hardness ranged from 1.49 N/m2 to 1.54 N/m2. All five soap types fulfilled SNI standards, but the soaps containing 15 g and 17.5 g of bentonite had a far better appearance. The chemical compositions of the bar soap composed of 15 g bentonite (BS 15) and the bar soap composed of 17.5 g bentonite (BS 17.5) were calculated using material balance and compared by Energy Dispersive X-ray (EDX) analysis. The EDX analysis revealed that both BS 15 and BS 17.5 contained the Si and Al metals originating from the bentonite. No heavy metals considered harmful to skin health (e.g., Hg, Pb, As, or Cd) were detected. Scanning electron microscopy (SEM) of the topography and texture of BS 15 and BS 17.5 revealed a more even distribution of Si and Al throughout BS 17.5 than in BS 15. BS 17.5 was therefore deemed the best formula as it meets SNI standards and has a better appearance and a more even mineral distribution.