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Super-paramagnetic iron oxide nanoparticles (SPIONs)/gelatin (gel)/polyvinyl alcohol (PVA) nanoparticles were designed and synthesized by the co-precipitation method and further modified with gel and PVA. These nanoparticles were used for the removal of Cu(II) and Zn(II) from aqueous solutions. The adsorbents were rich in different functional groups for chemisorption and showed effective adsorption properties. The adsorption of Cu(II) and Zn(II) on the SPIONs/gel and SPIONs/gel/PVA materials were investigated with respect to pH, adsorption kinetics, and adsorption isotherms. The adsorption data was fitted to the Langmuir, Freundlich, and Sips models at the optimum pH 5.2 (±0.2) over 60 min; SPIONs/gel showed maximum adsorption capacities of 47.594 mg/g and 40.559 mg/g for Cu(II) and Zn(II); SPIONs/gel/PVA showed those of 56.051 mg/g and 40.865 mg/g, respectively. The experimental data fitted the pseudo-second-order model, indicating that the process followed chemical monolayer adsorption. In addition, the SPIONs/gel/PVA showed better stability and Cu(II) adsorption efficiency than SPIONs/gel.

The purpose of this study was to produce a nanocomposite material by modifying and combining natural montmorillonite clay from the Khumuult deposit with multi-walled carbon nanotubes. Clay and multi-walled carbon nanotubes were pre-treated separately in several steps before combining them to produce a composite material. Mechanical processing was used to enrich the mineral montmorillonite from natural clay samples. The enriched montmorillonite sample was then autoclaved in alkali (NaOH), and the amount of total silica in the clay sample decreased from 38.4% to 21.7% in X-ray fluorescence analysis, indicating that the alkali treatment was effective. After functionalization, Fourier transform infrared spectroscopy (FTIR) spectroscopic analysis revealed the intensity of the amine group at 1540 and 2356 cm-1 , proving that the amine group successfully interacted on the montmorillonite. Commercial multiwalled carbon nanotubes were oxidized and carboxylated to increase activity and yield a composite. The FTIR, X-ray diffractometer, Scanning Electron Microscope (SEM), and Raman spectroscopy were used to investigate the properties of composite materials. According to the test results, the chemical composition of the composite material was 19.65% carbon, 41.06% oxygen, 8.86% aluminum, 9.75% silicon, and 7.52% iron. SEM analysis of our synthesized composite material revealed that multi-walled carbon nanotubes were evenly distributed on the surface of the clay. Further, it is considered necessary to conduct a detailed study of the characteristics and applications of the composite materials synthesized. Монтмориллонит ба олон ханат нүүрстөрөгчийн нано хоолой бүхий нано композит материалын нийлэгжүүлэлт Хураангуй: Хөмүүлтийн ордын монтмориллонитын төрлийн байгалийн шаврыг олон ханат нүүрстөрөгчийн нано хоолойтой нийлэгжүүлж, нано композит материал гарган авах зорилгоор энэхүү судалгааны ажлыг гүйцэтгэлээ. Байгалийн шаврын дээжинд механик боловсруулалт хийж монтмориллонитыг баяжуулсан. Баяжуулсан дээжинд автоклавын аргаар шүлтийн боловсруулалт хийж үр дүнг рентгенфлуоросценцын аргаар тодорхойлоход, шаврын дээж дэх нийт цахиурын оксидийн хэмжээ 38.4%-иас 21.7% болж буурсан нь шүлтийн боловсруулалт үр дүнтэй явагдсаныг харуулж байна. Шүлтийн боловсруулалт хийсэн шаврыг гексаметилэндиаминаар үйлчлэн амин (-NH2) бүлгийг суулгасан бөгөөд нил улаан туяаны спектроскопын шинжилгээгээр амин бүлгийн эрчим илэрсэн. Худалдааны олон ханат нүүрстөрөгчийн нано хоолойг исэлдүүлэн, карбоксилжүүлж бэлтгэсэн. Шавар болон олон ханат нүүрстөрөгчийн нано хоолойг тус тусад нь боловсруулалт хийсний эцэст композит материалыг химийн аргаар нийлэгжүүлэн гарган авсан. Композит материалын шинж чанарыг судлахдаа нил улаан туяаны спектрометр, рентгендифрактометр, сканнинг электрон микроскоп болон раман спектроскопын шинжилгээний аргыг ашигласан. Туршилтын дүнгээс харахад, композит материал нь химийн найрлагын хувьд нүүрстөрөгч 19.65%, хүчилтөрөгч 41.06%, хөнгөнцагаан 8.86%, цахиур 9.75%, төмөр 7.52% агуулгатай байсан ба шаврын гадаргуу дээр олон ханат нүүрстөрөгчийн нано хоолой жигд тархан сууж, композит материал нийлэгжсэн болох нь сканнинг электрон микроскопын шинжилгээний дүнгээс харагдаж байв. Цаашид гарган авсан композит материалын шинж чанарын болон хэрэглээний судалгааг нарийвчлан хийх шаардлагатай гэж үзэж байна. Түлхүүр үг: шавар, механик боловсруулалт, шүлтийн боловсруулалт, автоклав.

Acid activation is the most commonly used method to enhance the chemical and physical properties of clay minerals. Porous structure formation behavior depends on the crystal structure of clay minerals. Within the same structure of clay minerals, their resistance to acid also varies. Acid leaching has been used to increase the surface area of clay minerals and obtain solids with high porosity and many acidic sites. This paper is focused on the results of acid leaching of Mongolian clay minerals (montmorillonite and muscovite). Both clay minerals belong to a group of phyllosilicates with the 2:1 crystal structure. The influence of acid concentration and leaching time on the porous properties of silica was studied. Initially, the montmorillonite was pre-treated by a simple physical purification methods. The montmorillonite and muscovite were acid leached by a 10% hydrochloric acid solution in an autoclave at 120°C for 10h. X-ray diffraction (XRD), X-ray fluorescence analysis (XRF), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and the surface area used for characterization of the raw and leached samples. The surface area of leached montmorillonite increased up to 77% and muscovite up to 63%. Clay mineral’s swelling character and isomorphic substitution of the octahedral layer show the main influence on porous structure formation.