Clay Mica Research Articles

Fabrication of two-dimensional biotite nanosheets from natural biotite clay as a potent antibacterial agent

Since graphene’s exodus, layered materials’ exfoliation to two-dimensional (2D) nanosheets has attracted much attention. The primary layered materials are composed of weak van der Waals interlayer forces and strong intralayer bonds. Biotite (BTT) is one of the members of mica clays, which has stronger interlayer forces. In this study, three various procedures have been reported to exfoliate BTT. In the first method, ultrasound waves weakened the interlayer forces and so caused the exfoliation of the BTT to 2D nanosheets. In the second route, thermal and facile exfoliation of BTT intercalated compounds were combined. In the third one, a thermal exfoliation method was performed. These improved synthesis methods for producing few-layered exfoliated BTT (BTN) nanosheets, which are cost-effective, reproducible, and scalable, obtained BTNs with thicknesses of 10–50 nm, while the specific surface areas were increased by 4 times. The high specific surface area and sharp edges of BTN provide higher potentials for the decomposition of Escherichia coli and Staphylococcus aureus cells. The bactericidal effect of the BTNs against different bacteria was evaluated through the colony-forming unit (CFU) procedure and the minimum inhibitory concentration (MIC) quantities was subsequently measured. According to the results, after exfoliation, the antibacterial performance was improved about 8 times.

Solid-State Characterization of Heteropolyacid-Phyllosilicate Complexes: Structural, Morphological and Thermal Properties

We have previously described the complex formation from a synthetic smectite clay, Sumecton SA (SSA), and the heteropolyacid (HPA), 12-phosphotungstic acid (PTA). Three new synthetic layered aluminosilicate clays of the smectite- [Lucentite SWN (SWN)] and (fluoro)mica-type [Tetrasilicic mica (TSM); Somasif ME100, (SME)] have been self-assembled with PTA, at a specific PTA-clay weight ratio of 5. New protogenic inorganic complexes have been prepared for the future fabrication of proton exchange membrane for fuel cell devices (PEMFC). Complex formation, thermal and structural properties of PTA-phyllosilicate complexes have been investigated using EDX, XRD, SEM, and DRIFT. EDX indicates that complexes incorporate a substantial amount of PTA (50-60% w/w) and that a moderate depletion of Mg2+ ions from octahedral layers of micas clays occurs during the process compared to smectite ones. In contrast, a significant amount of F is removed from the octahedral framework of the mica clays. DRIFT experiments indicate that the Keggin structure is preserved within all complexes and that complex formation predominantly involves the external oxygen (W-Od) of PTA. According to Patterson functions, coherence lengths - which reflect for the virgin clays the extent of the longitudinal platelet stacking (Lc) - of the two smectite clays (Lc ~25 Å) are significantly lower than for their analogous of the mica type (Lc = 180-225 Å). Clays in complexes are characterized by the loss of in-plane organization but are still partially ordered. The nature of the order is still speculative but could be related to the formation of a new inorganic PTA species formed during the complex formation. Compared to the virgin clays, the order of smectite complexes is maintained in the same range (Lc = 27-42 Å) while for mica complexes, coherence lengths are dramatically reduced to ~ 60 Å. All PTA-activated complexes contain a substantial amount of amorphous silica, which tends to increase when heated at temperatures above 280 oC. However, the Keggin structure within the complexes is at least stable up to 280 oC and even, for the most robust TSM complex, up to 450 oC.

The Influence of Mg-Impurities in Raw Materials on the Synthesis of Rankinite Clinker and the Strength of Mortar Hardening in CO2 Environment.

The idea of this work is to reduce the negative effect of ordinary Portland cement (OPC) manufacture on the environment by decreasing clinker production temperature and developing an alternative rankinite binder that hardens in the CO2 atmosphere. The common OPC raw materials, limestone and mica clay, if they contain a higher MgO content, have been found to be unsuitable for the synthesis of CO2-curing low-lime binders. X-ray diffraction analysis (ex-situ and in-situ in the temperature range of 25-1150 °C) showed that akermanite Ca2Mg(Si2O7) begins to form at a temperature of 900 °C. According to Rietveld refinement, the interlayer distances of the resulting curve are more accurately described by the compound, which contains intercalated Fe2+ and Al3+ ions and has the chemical formula Ca2(MgO0.495·FeO0.202·AlO0.303)·(FeO0.248·AlO·Si1.536·O7). Stoichiometric calculations showed that FeO and Al2O3 have replaced about half of the MgO content in the akermanite structure. All this means that only ~4 wt% MgO content in the raw materials determines that ~60 wt% calcium magnesium silicates are formed in the synthesis product. Moreover, it was found that the formed akermanite practically does not react with CO2. Within 24 h of interaction with 99.9 wt% of CO2 gas (15 bar), the intensity of the akermanite peaks does not practically change at 25 °C; no changes are observed at 45 °C, either, which means that the chemical reaction does not take place. As a result, the compressive strength of the samples compressed from the synthesized product and CEN Standard sand EN 196-1 (1:3), and hardened at 15 bar CO2, 45 °C for 24 h, was only 14.45 MPa, while the analogous samples made from OPC clinker obtained from the same raw materials yielded 67.5 MPa.

Improvement of the Pozzolanic Properties of Calcined Mica Clay

Improvement of the Pozzolanic Properties of Calcined Mica Clay

Thermoplastic Starch and Mica Clay Composites as Biodegradable Mulching Films

Thermoplastic Starch and Mica Clay Composites as Biodegradable Mulching Films

An experimental investigation into the use of mica as a material for the stabilisation of marginal clays in construction

The scarcity and cost of high-quality construction materials have resulted in their use being reserved for the construction of structures that experience relatively high stress, such as roads with high traffic volumes. Consequently, mechanically improved abundant marginal materials are common in relatively low stress construction applications such as landscaping, low-volume paved roads and fill material for flood embankments. In clays, mechanical improvement is commonly achieved through the addition of chemical stabilizers such as lime, bitumen, cement, and fly ash. However, these chemical stabilizers are associated with high cost and a large carbon footprint. Here, we present the first research demonstrating that clays can be mechanically improved through the addition of mica. Mica wastes are generated in significant volume as a by-product from the mining of relatively valuable materials. This paper explores the use of mica to improve the ultimate limit state of marginal clays for use as construction material. Kaolin clay was prepared with muscovite sand and muscovite silt in variable fractions (0%, 2.5%, 10% and 30% muscovite fraction). The hydraulic and mechanical response of the composite materials were investigated through one-dimensional compression and direct shear testing. The most notable finding is that, at very low normal stresses (≤100 kPa), a relatively small fraction of mica is sufficient to shift the angle of shearing resistance of the composite, from the value for pure clay (ϕ’∼ 17°) towards the value for pure muscovite (ϕ’ ∼26°). X-ray computed tomography scans of the consolidated and sheared samples show that the relatively high strength of the mica clay composite at low normal stress is due to a fold-like mode of deformation observed in shearing. This mechanism appears to be suppressed at high stresses with the shear band likely developing through the clay matrix. As a result, the composite exhibits the same friction angle of the clay alone at high stresses.

An unfamiliar physeteroid periotic (Cetacea: Odontoceti) from the German middle–late Miocene North Sea basin at Groß Pampau

Abstract. The Miocene mica clay locality of Groß Pampau, known for numerous and partly spectacular finds of marine mammals is becoming more and more a prominent site that bears the potential to resolve questions regarding taphonomic relationships and to interpret life communities of the ancient North Sea because of its rich faunal assemblage including invertebrates and other remains of various vertebrate organisms. In the present work we describe a right periotic of Physeteroidea with morphological characters so far unknown from other sperm whales. The periotics of the middle Miocene Aulophyseter morricei demonstrate the closest resemblance to the Groß Pampau specimen in their overall appearance and in the general arrangement and proportions of single structures, particularly of the anterior process and pars cochlearis. A great similarity is also documented with periotics of the living sperm whale, Physeter macrocephalus, especially regarding the shape and disposition of the anterior process and the bony element located dorsally to the accessory ossicle. Kogiid periotics differ strongly from that of the Groß Pampau specimen by having an inflated and short anterior process and, typically, three well-defined spines on it. A new taxonomic naming of the Groß Pampau periotic is not appropriate at this stage, although it might demonstrate the existence of a so-far undescribed physeteroid species. Additionally, its systematic position remains yet unclear and it is unknown at this point if it could belong to Hoplocetus ritzi, another physeterid, whose fragments were discovered in the same locality, or to another, already-described taxon, of which the periotic is still unknown.

Estimating the elastic properties of mica and clay minerals

The orientation distribution of the platelets of the phyllosilicate minerals, including mica clays, significantly affects the elastic velocities and anisotropy of shales. Despite a substantial number of publications on shale elasticity in general and, more specifically, on the elastic properties of clay minerals (phyllosilicates) and clay mineral aggregates with varying degree of the platelet preferred orientation, our understanding of these properties is still rather limited. Elastic properties of mudrocks, influenced by the presence of variously oriented phyllosilicates, such as muscovite, illite, and illite/smectite platelets, can be well-constrained if not accurately estimated by a combination of microstructural observations and semiempirical rock-physics models for conventional shale. The orientation distribution data from published literature are used to relate the maximum platelet pole orientation density to the double median orientation angle [Formula: see text] with respect to the bedding plane, both of which relate to the platelet alignment strength. The [Formula: see text] angle is an equally intuitive orientation distribution parameter, which we rely upon in a heuristic approach to model bedding-normal anisotropic elastic moduli and P- and S-wave velocities of zero-porosity clay (matrix) aggregates as a function of the median orientation angle of clay platelets composing these aggregates. It is demonstrated that zero-porosity illite-dominated aggregates with perfect platelet alignment ([Formula: see text]) should have the platelet-normal elastic moduli of [Formula: see text], [Formula: see text], and a [Formula: see text] ratio of approximately [Formula: see text]. The platelet-normal moduli and mineral density of muscovite are significantly greater than those of illite, whereas the respective moduli of the smectite-dominated clay composite are smaller (and the velocity ratio is greater) than those estimated for illite-dominated clays. Finally, it is also shown that the platelet-normal velocity ratio gradually decreases in the smectite, illite, and muscovite series.

Defluoridation of drinking water using coalesced and un-coalesced mica

This is a sorption study that focused on the use of mica clay mineral grouped into mica untreated, activated mica at 800 °C, mica impregnated separately with iron and aluminium for defluoridation of water. In this study, characterization of adsorbent was done by using XRF and XRD and quantification of fluoride by using fluoride ion selective electrode. Characterization of adsorbent showed the presence of SiO2, CaO, P2O5, Fe2O3 and Al2O3 in the adsorbent. XRD exhibited higher composition of illite, calcite, quartz and albite. Batch experiments were conducted by using a homogeneous mixture of water having 16 mg/L of fluoride. The removal efficiencies of mica alone, activated mica at 800 °C, mica impregnated with iron and mica impregnated with aluminium were found to be 76.02%, 90.21%, 94.40% and 96.88%, respectively. Activated mica and coalesced mica are better adsorbents than mica alone. The optimized pHs were 7.3, 4.4, 7.5, doses of 10, 9 and 8 g, contact time of 40, 35 and 30 min for activated mica, mica impregnated with iron and mica impregnated with aluminium, respectively. The adsorption process obeyed Freundlich model for mica impregnated with aluminium indicating monolayer mechanism, whereas activated mica and mica impregnated with iron agreed with both Freundlich and Langmuir models indicating both monolayer homogeneous and heterogeneous surface conditions. From the kinetic perspective, the fluoride adsorptive reaction followed the pseudo-second-order model. Therefore, activated and modified mica are alternative adsorbents for defluoridation of water.

Petrografická charakteristika spodnokarbonských ryolitových tufitů z vrtů v lomu Výkleky (moravické souvrství, kulmská pánev Nízkého Jeseníku)

Two layers of volcanoclastic rock with thickness 40 and 210 cm were identified in core-samples, obtained by exploration drilling in the Výkleky quarry which was established in Lower Carboniferous sediments of the Moravice Formation (Moravo-Silesian Culm basin in the Nízký Jeseník Mts.). The volcanoclastics are represented by tuffaceous sandstones to tuffaceous conglomerates. These tuffites consist of a mixture of pyroclastic and epiclastic material, mainly fragments of strongly carbonatised porphyritic rhyolite, less of quartz shards, argillitised feldspars (K-feldspar and albitised plagioclase), chloritised biotite leaflets and muscovite. Lithic and mineral fragments are surrounded by lutitic matrix. Volcanic glass was completely replaced by mixture of quartz, alkali feldspars, chlorite and “clay micas” (phengitic illite-muscovite). Chemical composition of albite from rhyolite fragments and tuffite matrix is similar (An01 - 04), chlorite chemically corresponds to chamosite (XMg = 0.39 - 0.47; Si = 2.72 - 3.08 apfu). Pyrite and carbonates (calcite and side-rite to Mg-rich siderite) often fills cracks in the rock. Studied volcanoclastic rocks represent products of extrabasinal Lower Carboniferous terrestrial explosive volcanism whose activity probably culminated during the sedimentation of the Moravice Formation.

ГЛИНЫ ТАВДИНСКОЙ СВИТЫ ЭОЦЕНА: ЛИТОГЕОХИМИЧЕСКИЕ И СЕДИМЕНТОЛОГИЧЕСКИЕ АСПЕКТЫ (КЫШТЫРЛИНСКОЕ МЕСТОРОЖДЕНИЕ, ЗАПАДНАЯ СИБИРЬ)

Актуальность. Минеральный состав глин тавдинской свиты изучался неоднократно. Полученные результаты, содержащиеся в геологических отчетах и немногочисленных опубликованных работах, зачастую слабо коррелируются друг с другом. Подобное противоречие вызвано отбором проб для технологических испытаний с различных участков, которые относятся к двум подсвитам, имеющим ряд отличий. Возраст, стратиграфическое положение и химико-минералогические особенности пород, слагающих тавдинскую свиту, остаются дискуссионными и актуальными вопросами, что требует дополнительных исследований. Детальное изучение литологии глин тавдинской свиты принимает важное значение в связи с планами по расширению сырьевой базы и потребностью перепрофилизации части производственных мощностей на выпуск новой товарной продукции. Цель работы: изучение вещественного состава глин тавдинской свиты эоцена Западной Сибири для выявления их генезиса и практического использования Методы: полевые исследования, рентгеноструктурный анализ, рентгенофлуоресцентный анализ, определение огнеупорности, масс-спектрометрия с индуктивно-связанной плазмой, сканирующая электронная микроскопия, литолого-петрографический анализ в шлифах. Результаты. Представлены результаты исследований химического и минерального составов, особенностей литологии и микростроения глинистых пород из Кыштырлинского участка (Тюменская область). Глинистые породы обладают определенной вариативностью минерального состава, но неизменным остается глинистый слюдистый смешаннослойно-смектитовый матрикс. В нижней подсвите глинистая масса пород сложена преимущественно иллитом и смешанослойными образованиями иллит-смектитового состава. Глины верхней подсвиты больше соответствуют каолинит-иллит-монтмориллонитовому типу с примесями пирита, минералов кремнезёма, сульфатов, карбонатов и органического вещества. Формирование таких смешаннослойных масс, вероятно, обусловлено трансформацией обломочных минералов и первичного глинистого субстрата. Установленное распределение редкоземельных элементов индицирует существенные изменения в восстановительно-окислительных условиях морского бассейна на различных этапах его существования. Изученные глины рассматриваются как полиминеральные.

Chemical equilibrium of groundwater with minerals of the host rocks in Upper Jurassic sediments (Arctic regions of Western Siberia)

The results of thermodynamic calculations for a water-rock system in the Upper Jurassic deposits of the Arctic regions of Western Siberia are presented. In the area under investigation the groundwaters have been identified with mineralization up to 63.3 g/L and various chemical composition and genesis. Despite the long interaction with the rock (150-160 ma) equilibrium with endogenous minerals (albite, microcline and anorthite) is practically not observed. At the same time, groundwaters are in equilibrium with clay minerals and micas, such as: Caand Na-montmorillonites, kaolinite, paragonite, margarite, illite, muscovite and Mg-chlorite. The establishment of a balance of groundwater with primary aluminosilicate minerals is also affected by interactions with carbonate minerals. The differences in composition of groundwater in equilibrium with certain aluminosilicates and carbonates indicate that the mineral changes are formed from a solution of a strictly defined chemical composition in an appropriate geochemical environment.

The Role of Soil Mineralogical Characteristics in Sustainable Soil Fertility Management: A Case Study of Some Tropical Alfisols in Nigeria

ABSTRACTThe pedogenic horizons of nine profile pits dug across three toposequences were studied to determine the soil mineralogical characteristics and its implications on sustainable management of the fertility of some tropical Alfisols in Nigeria. Results showed that the epipedon which were predominantly ochric had textures that ranged from sand to sandy loam, while the subsurface (B/Bt) horizons had sandy clay loam to sandy clay texture and were gravelly (31.79–83.04%). The soil reaction ranged from strongly acid to neutral (pH 5.10 to 7.05). Calcium and magnesium dominated the exchange sites and accounted for about 75% of the exchangeable bases. Illite/mica and kaolinite were the dominant minerals in the clay fractions, while quartz, mica, and feldspars dominated the fine sand and silt fractions of the soils. While the presence of illite and mica could be important for potassium nutrition in these soils, kaolinite and oxides of iron could also cause phosphorus fixation.

Investigation of the firing temperature effects on clay brick sample; Part-I: Mineralogical phase characterization

Present research work was focused to investigate the firing temperature effects on mineralogical phase composition of nine clay bricks collected from the brick factory of Kathmandu valley using X-ray diffraction (XRD) patterns and Fourier transform infrared (FTIR) spectra analyses. Main mineralogical phases of quartz, feldspars, spinel, mullite and hematite in the brick specimens fired at different firing temperatures including muscovite type of mica mineral in the sun-dried brick specimen are identified from XRD and FTIR analyses. Disappearance of the muscovite type of mica clay mineral with feldspars enhanced to form alumina rich spinel phase at firing 900° to 1000° C, and finally the primary mullite phase in the fired clay brick samples is clearly observed at 1100° C firing temperature.BIBECHANA 16 (2019) 122-130

Influence of low-pozzolanic activity calcined mica clay on hydration and hardening of Portland cement

This study investigated the possibility of using artificial materials obtained during combustion of mica clay as an additive for Portland cement. The mica clay granules were burned at 700–1100°C for 1 h. It was considered that the pozzolanic activity of the investigated mica clay would depend on the combustion temperature. The highest pozzolanic activity (134 mg calcium oxide (CaO)/g) was observed in the samples calcined at a temperature of 900°C. In the samples, 5, 10, 15 and 25% (by weight) of the Portland cement was replaced with calcined additive at the temperature of 900°C. The samples were then hardened for 28 d under normal conditions. Owing to relatively low pozzolanic activity, the pozzolanic reaction in the samples with the additive up to 28 d of hydration was not noticeable. However, calcined mica clay additive acted as a microfiller and significantly increased the rate of hydration of Portland cement clinker minerals. The calcined mica clay additive had a positive effect on the compressive strength of samples cured for 28 d under normal conditions because up to 15 wt% of ordinary Portland cement can be replaced with the additive being investigated without impairing the strength class of the cement.

Heterogeneous catalytic transformation of vegetable oils into biodiesel in one-step reaction using super acidic sulfonated modified mica catalyst

Herein, conversion of castor oil and jatropha oil were converted into their corresponding biodiesels using highly acidic heterogeneous catalyst prepared by modification of silane mica clay in one step reaction. The prepared catalyst was characterized using different spectroscopic methods. The conditions of biodiesel production were optimized to obtain the maximum yield including: oil to methanol ratio, catalyst ratio, temperature, and reaction time. The specifications of the obtained products were comparable to (American Society for Testing and Materials) ASTM specifications. The analysis showed that the conversion of castor oil into biodiesel involves two reactions. The first is the transesterification of the triglycerides to the corresponding methyl esters, and the second is the etherification reaction of the hydroxyl groups of ricinoleate moieties to the corresponding methyl ether. The role of catalyst activity in the conversion reactions was described, and the different mechanisms involved in the conversion reaction were described.

Geology and environments of subglacial Lake Vostok.

The reconstruction of the geological (tectonic) structure and environments of subglacial Lake Vostok is based on geophysical surveys and the study of mineral particles found in cores of accreted ice and frozen lake water (sampled after the lake was unsealed). Seismic reflection and refraction investigations conducted in the southern part of Lake Vostok show very thin (200-300 m) sedimentary cover overlying a crystalline basement. Most of this thin veneer is thought to have been deposited during temperate-glacial conditions in Oligocene to Middle Miocene time (ca 34-14 Ma). The composition of the lake-bottom sediments can be deduced from mineral inclusions found in cores of accreted ice. Inclusions are represented by soft aggregates consisting mainly of clay-mica minerals and micrometre-sized quartz grains. Some of these inclusions contain subangular to semi-rounded rock clasts (siltstones and sandstones) ranging from 0.3 to 8 mm in size. In total, 31 zircon grains have been identified in two rock clasts and dated using SHRIMP-II. The ages of the studied zircons range from 0.6 to 2.0 Ga with two distinct clusters between 0.8 and 1.15 Ga and between 1.6 and 1.8 Ga. Rock clasts obviously came from the western lake shore, which is thus composed of terrigenous strata with an age of not older than 600 Ma. The sedimentary nature of the western lake shore is also confirmed by seismic refraction data showing seismic velocities there of 5.4-5.5 km s(-1) at the bedrock surface. After Lake Vostok was unsealed, its water (frozen and sampled next season) was also studied with scanning electron microscopy and X-ray microprobe analysis. This study showed the existence of calcium carbonate and silica microparticles (10-20 μm across) in frozen water.

Soilless plant growth media influence the efficacy of phytohormones and phytohormone inhibitors.

Plant growth regulators, such as hormones and their respective biosynthesis inhibitors, are effective tools to elucidate the physiological function of phytohormones in plants. A problem of chemical treatments, however, is the potential for interaction of the active compound with the growth media substrate. We studied the interaction and efficacy of propiconazole, a potent and specific inhibitor of brassinosteroid biosynthesis, with common soilless greenhouse growth media for rice, sorghum, and maize. Many of the tested growth media interacted with propiconazole reducing its efficacy up to a hundred fold. To determine the molecular interaction of inhibitors with media substrates, Fourier Transform Infrared Spectroscopy and sorption isotherm analysis was applied. While mica clay substrates absorbed up to 1.3 mg of propiconazole per g substrate, calcined clays bound up to 12 mg of propiconazole per g substrate. The efficacy of the gibberellic acid biosynthesis inhibitor, uniconazole, and the most active brassinosteroid, brassinolide, was impacted similarly by the respective substrates. Conversely, gibberellic acid showed no distinct growth response in different media. Our results suggest that the reduction in efficacy of propiconazole, uniconazole, and brassinolide in bioassays when grown in calcined clay is caused by hydrophobic interactions between the plant growth regulators and the growth media. This was further confirmed by experiments using methanol-water solvent mixes with higher hydrophobicity values, which reduce the interaction of propiconazole and calcined clay.

Ab initio investigations of dioctahedral interlayer-deficient mica: modelling 1 M polymorphs of illite found within gas shale

In this investigation we create a variety of dioctahedral, interlayer (cation)-deficient mica clay mineral models of the 1 M -illite series, using the ab initio method of density functional theory (DFT), employing plane waves, pseudo potentials, and super cells. The structures we create are modelled on an average formula of illite such as (Ca 0.059 , K 0.655 )(Si 3.597 , Al 0.403 )(Fe 0.628 , Al 0.969 ,Mg 0.428 )O 10 (OH) 2 , as well as existing crystal structures and experimental data. This study investigates the relative positions of both octahedral and tetrahedral cation substitutions ( e.g . Fe 3+ for Al 3+ and Al 3+ for Si 4+ ) in both trans- and cis-vacant structures. The purpose of this work is to create robust, representative models of single layers (I) and double layers (I-I) of illite found within gas shale, that can be used in future investigations. We examine lattice parameters, interatomic distances of tetrahedral and octahedral sheets, K–O distances, and K positions, and find reasonable agreement with experimental data, and excellent agreement with simulated data of similar structures. Finally, to enable experimental characterization of samples of illite with different compositions, we provide simulated X-ray powder diffraction (XRPD) patterns including up to the first ten ( h k l ) reflections, and find characteristic identifiers of trans- and cis-vacant micas in agreement with previous theoretical and experimental studies. We conclude that the models we create are feasible models of I and I-I layers of illite found within shale and are ready for use in future work.

Few-Layer Graphene-Based Saturable Absorbers Employing Mica Dispersant for Fiber Lasers

Few-layer graphene-based saturable absorbers (SAs) employing the novel fluorinated mica clay (mica) dispersant for stable mode-locked fiber lasers (MLFLs) are developed. Optical linear absorbance spectrum of graphene-in-polymer film is observed without absorption peak from 400 to 2000 nm. Optical nonlinearities of 1, 2, and 3 wt% graphene-based SAs are initially screened and optimized to be 3 wt% as the highest modulation depth value of 2.46%. By utilizing the mica dispersant for graphene, the developed SA exhibits a stable MLFL showing a pulse width of 382 fs, a bandwidth of 6.80 nm, and a time-bandwidth product of 0.322 at fundamental soliton-like operation. The use of plate-like mica to uniformly disperse graphene-based SAs is crucial for producing stable, ultrafast, and high-performance MLFLs.