Browsing by Author "Kalmakhanova, Marzhan"
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- Assisted hydrothermal carbonization of agroindustrial byproducts as effective step in the production of activated carbon catalysts for wet peroxide oxidation of micro-pollutantsPublication . Díaz de Tuesta, Jose Luis; Saviotti, Marcus Chamahum; Roman, Fernanda; Pantuzza, Gabriel F.; Sartori, Hiram J.F.; Shinibekova, Assem A.; Kalmakhanova, Marzhan; Massalimova, Bakytgul Kabykenovna; Pietrobelli, Juliana Martins Teixeira; Lenzi, Giane G.; Gomes, HelderThis work deals with the valorisation of bagasse of sugarcane – BC, bagasse of malt – BM and seed of chia – SC, through its transformation into pyrochars, hydrochars and activated carbons (ACs) by pyrolysis, hydrothermal carbonization (HTC) and sequential HTC and pyrolysis, respectively. The HTC process was carried out in the presence of H2O, FeCl3 and H2SO4 solutions. The materials resulting by HTC in the presence of FeCl3 revealed the highest burn-off, but the contents of carbon released into the liquid phase, measured as total organic carbon, and to the gaseous phase, determined by carbon balance, depend strongly on the carbon precursor. In this sense, BC generates more volatile organic compounds (up to 34% of the initial carbon content), followed by BM (< 15%) and SC (< 5%) in their HTC and pyrolysis (70%). The pyrochars, hydrochars and ACs prepared from BC also show the highest specific surface areas (SBET < 447 m2⋅g-1) when compared to the specific surface areas of the materials prepared from BM and SC. The carbon-based materials prepared with FeCl3 show the highest catalytic activity, but iron leaching into solution is observed. On the other hand, the materials prepared with H2SO4 show high activity, enabling its application in successive cycles and the complete degradation of caffeine in concentrations ranging from 1 to 100 mg⋅L-1, after 5–60 min of reaction.
- Methods of preparation and physico-chemical characteristics of organic modified clays with grafted organoaloxidesPublication . Serikbayeva, Aizhan Mukhammedalievna; Kalmakhanova, Marzhan; Gomes, Helder; Shagraeva, Bibigul Bekenovna; Shertaeva, Nailya TurdygalievnaThe main sources of many environmental problems associated with the formation of wastewater are industrial enterprises that release water streams containing pollutants. Wastewater treatment is a complex task that requires a combination of different methods to achieve maximum efficiency. Increasing the efficiency of removing heavy metals, nutrients, anionic pollutants and organic compounds from liquid media is one of the most acute environmental problems. In recent years, the danger of environmental pollution with toxic metal ions as a result of wastewater discharge from electroplating, mining and battery industries has been growing. Natural and modified clays have a large surface area and a high ion exchange capacity, which allows them to be used as effective adsorbents for the removal of heavy metals from wastewater. In this regard, scientific interest is growing in the creation of new environmentally friendly technical solutions and inexpensive materials (adsorbents and /or catalysts) based on clays. Their use as an adsorbent and catalyst for wastewater of the chemical industry is an urgent and priority task. Adsorbents or catalysts were prepared during the purification of environmentally hazardous compounds in wastewater. The clay was thoroughly washed, heated 800С. With a stirrer for several days before the organic compound was absorbed for drying and application of the organic compound. Various analyses were used to describe adsorbents, such as infrared spectroscopy (IR), X-ray diffraction (X-ray diffraction), differential thermal analysis (DTA), element analysis, etc. Clay-based materials were obtained from natural clays and evaluated during wastewater treatment using model pollutants in aqueous solutions. Natural clays were collected from Aktobe deposits in the region of Kazakhstan. It was found that the modified samples exhibit higher sorption properties compared to enriched clay.
- MnFe2O4/ZHETISAY composite as a novel magnetic material for adsorption of Ni(II)Publication . Baimuratova, Zhaina; Kalmakhanova, Marzhan; Shynazbekova, SH.S.; Kybyraeva, N.S.; Díaz de Tuesta, Jose Luis; Gomes, HelderThis paper deals with the preparation of magnetic adsorbents from natural clays for the adsorption of Ni(II) from aqueous matrices. The phase composition and structure parameters of natural clays and their modified forms, as well as their application as adsorbing agents for the purification of drinking water and their sources were studied. In the study, natural clays from the Zhetisay deposit of Kazakhstan were used to obtain magnetic composites by chemical coprecipitation and applied as effective adsorbents to remove Ni(II) from water. The formation of sorbents by magnetic nanoparticles is an urgent task of our time. This is due to the needs of various branches of science and technology in magnetically controlled sorbents. The advantage of such sorbents in comparison with natural sorbents is the ability to control them using a magnetic field. Sorbents with magnetic properties are used for contact cleaning of substances, which greatly simplifies the sorption process and the completeness of the sorbent processing. The use of such materials makes it possible to replace the mechanical separation stage, which is one of the labor-intensive stages of this process. Magnetic pillared clays were obtained by intercalation of iron and manganese cations in the region between the clay silicate layers, upon hydrolysis of a solution of Fe2(SO4)3·9H2O and MnCl2·4H2O with NaOH. The intercalated clay is then dried and calcined at 400°C for 3 h. The basic physical and chemical properties were stu died by XRD, elemental analysis, FTIR and atomic emission spectral analysis (AES). The obtained magnetic pillared clays (MnFe2O4/Zhetisay) showed better characteristics than natural clays. The results of adsorption revealed that the optimal adsorption conditions were observed at pH 6.
- New magnetic clays MnFe2O4/Shymkent for removal of heavy metals from wastewaterPublication . Baimuratova, Zhaina; Ermekov, Sayat; Silva, Adriano S.; Gomes, Helder; Kalmakhanova, MarzhanThis paper reports the development of a new method. Production of modified clay with magnetic properties based on natural clay from the Shymkent deposit (MnFe2O4/Shymkent nanocomposite), determination of its chemical composition and structure, as well as the study of basic physicochemical properties. The resulting magnetic nanocomposite was then used as an adsorbent to remove nickel (II) ions from wastewater. The prepared magnetic nano composite was then used as adsorbent to remove Ni (II) ions from wastewater, and the optimal conditions for determining thermodynamic and kinetic parameters were evaluated. It was determined that the natural сlay from the Shymkent deposit is a promising material for the modification of the materials. The advantage of such magnetic adsorbents in comparison with the natural materials used as adsorbents is their higher adsorption capacity and theability to control them using a magnetic field. To characterize the modified adsorbents, various assays were used, such as EMP andXRD analysis. The textural properties of the materials were determined by analyzing N2 adsorption-desorption isotherms at 77 K. It is shown that almost all textural and adsorption characteristics of MnFe2O4/Shymkent have significantly improved as a result of the modification made. It was concluded that the MnFe2O4/Shymkent adsorbent obtained in the work can be used for effective wastewater treatment to remove nickel ions.
- Novelty pillared clays for the removal of 4-nitrophenol by catalytic wet peroxide oxidationPublication . Kalmakhanova, Marzhan; Massalimova, Bakytgul Kabykenovna; Díaz de Tuesta, Jose Luis; Gomes, Helder; Nurlibaeva, A.A.One solution passes through the study of wastewater treatment by catalytic wet peroxide oxidation (CWPO).In this work, catalysts based on pillared clays with Zrcations have been prepared from nature clays of Kazakhstan, which were obtained from Zhambyl region of Karatau,Akzhardeposit, to be tested in catalytic oxidation of 4-nitrophenol, used as amodel pollutant. The Zr-pillared clay showed higher activity than nature clays in 4-nitrophenol oxidation.
- Obtaining of zirconium catalysts based on pillared clays for peroxide oxidation of 4-nitrophenolPublication . Kalmakhanova, Marzhan; Massalimova, Bakytgul Kabykenovna; Gomes, Helder; Díaz de Tuesta, Jose Luis; Tsoy, Irina; Aidarova, A.O.Natural resources, including abundant and cheap natural clays in the southern regionare one of the main wealth of the Republic of Kazakhstan. The chemical industry in Kazakhstanis being developedrapidly in recent years and there is an urgent need to find solutions for the treatment of wastewaters. This work aims to explore natural clays for the synthesis of low-cost pillared clays that can be used as catalysts in oxidation technologies for the treatment of wastewaters. Nitrophenols are commonly found in many types of wastewaters (plastic, pharmaceutical, paper or pesticide production).The purification of suchspecific wastewater according to classical schemes does not always ensure a safe level of pollution in waters discharged into water ponds. Thus, further development of the chemical industry will inevitably be associated with the need for more effective disposal of wastewater containing toxic products. 4-nitrophenol was used as a representative model compound in catalyst screening studies.Catalysts based on pillared clays modified with Zr4+cations were synthesized from natural clays of Karatau and Kokshetau deposits and investigated for the catalytic wastewater peroxide oxidation (CWPO) of 4-nitrophenol (4-NP) at 323 K. Pillared clays with Zr4+ showed the higher catalytic activity in the removal of 4-NP and Total organic carbon (TOC) by CWPO and selectivity for the formation of CO2 and H2O than natural clays.The best 4-NP and TOC conversion results were obtained by using the pillared clay from Karatau deposit as a catalyst. A complete removal of the contaminant was achieved after 2 hours with 97.3 % conversion.
- Occurrence of micropollutants in surface water and removal by catalytic wet peroxide oxidation enhanced filtration using polymeric membranes loaded with carbon nanotubesPublication . Silva, Adriano S.; Zadra Filho, Paulo Cesar; Ferreira, Ana Paula; Roman, Fernanda; Baldo, Arthur Pietrobon; Rauhauser, Madeleine; Díaz de Tuesta, Jose Luis; Pereira, Ana I.; Silva, Adrián; Pietrobelli, Juliana Martins Teixeira; Kalmakhanova, Marzhan; Snow, Daniel D.; Gomes, HelderMonitoring campaigns of contaminants of emerging concern (CECs) in surface waters is of utmost importance in evaluating the anthropogenic impact on riparian ecosystems. Beyond identifying pollutants and threats, treatment solutions are also needed to mitigate the adverse effects caused by polluted water discharged into the environment. For years, grab samples have been used to assess water quality, but the results can be misleading since contaminants are not always found due to the low and highly variable concentrations at which they are present in these matrices. Even in such small concentrations, the contaminants can be harmful to aquatic life. Therefore, for about three months, passive samplers were used to monitor the presence of pharmaceuticals in river water up- and downstream the discharge of a wastewater treatment plant (WWTP). Passive samplers were extracted, analyzed and the results were used to identify possible pollution composition and potential sources. Our campaign enabled the identification and quantification of 28 contaminants and showed that 27 increased in amount after WWTP discharge entered the river. The statistical analysis revealed the correlation between the pollutants, showed the oscillation in their amounts, and enabled the identification of specific pollutant groups that deserve attention for treatment, such as antibiotics and antidepressants. Moreover, an innovative catalytic wet peroxide oxidation (CWPO) intensified filtration process was investigated as a possible water treatment solution, using composite polymeric membranes loaded with carbon nanotubes (CNTs). Sulfamethoxazole (SMX) was selected as a model pollutant, and 85–90 % removals were achieved in continuous flow mode during 8 h (equivalent to 2255–2315 mg m-2 h-1).
- Performance and modeling of Ni(II) adsorption from low concentrated wastewater on carbon microspheres prepared from tangerine peels by FeCl3-assisted hydrothermal carbonizationPublication . Díaz de Tuesta, Jose Luis; Roman, Fernanda; Marques, Vitor da Costa; Silva, Adriano S.; Silva, Ana P. F.; Bosco, Tatiane; Shinibekova, Assem A.; Aknur, Sadenova; Kalmakhanova, Marzhan; Massalimova, Bakytgul Kabykenovna; Arrobas, Margarida; Silva, Adrián; Gomes, HelderThe presence of heavy metals in the environment as a consequence of human activity is an issue that has caught the attention of researchers to find wastewater treatment solutions, such as adsorption. In this work, hydrochars and activated carbon microspheres are prepared from tangerine peels as carbon precursor and FeCl3 as activating and structure-directing agent in the hydrothermal carbonization, allowing to obtain hydrochar microspheres ranging from 50 to 3615 nm. In addition, a pyrochar was prepared by pyrolysis of the same precursor. The activated carbon shows the highest surface area (SBET up to 287 m2 g–1), but the basicity of the pyrochar (1.83 mmol g-1, SBET = 104 m2 g–1) was determinant in the adsorption of Ni, being considered the carbon-based material with the highest uptake capacity of Ni. Isotherm and kinetic adsorption of Ni on the most representative activated carbon microsphere, pyrochar and hydrochar microsphere are assessed by 10 and 7 models, respectively.
- Pillared clay-based catalysts for treatment of 4-nitrophenol solutions by catalytic wet peroxide oxidationPublication . Kalmakhanova, Marzhan; Nurlybayeva, Aisha Nurlybaevna; Seitbekova, G.A.; Naurzkulova, Symbat Muratbekovna; Díaz de Tuesta, Jose Luis; Gomes, HelderThe constant development of technological processes aggravates the problem of pollution, due to a significant change in the composition of effluents, which makes necessary new (and/or improved) treatment methods and catalytic materials. In this sense, the use of natural clays in the synthesis of low cost pillared clays for application as catalysts in oxidation technologies for the treatment of wastewaters are relevant from an environmental and sustainable point of view. In this work, inexpensive natural clays from different regions of Kazakhstan (Akzhar, Karatau and Kokshetau) were used in the preparation of pillared clays for the catalytic oxidation of organic pollutants with H2O2. Since nitrophenols are commonly found in many types of industrial wastewaters (e.g. plastic, pharmaceutical, paper or pesticides industries), 4-nitrophenol (4-NP) was used as representative model compound in the catalyst screening studies. The pillaring process of the targeted natural clays involved the incorporation of active metals such as Zr,Fe and Cu, which were responsible by increasing the catalytic activity of the materials relatively to the natural clays. High conversions of TOC (85%) and of 4-NP (100%) were obtained with the Zr-pillared clay from the Akzhar region.
- Pillared clays from natural resources as catalysts for catalytic wet peroxide oxidation: Characterization and kinetic insightsPublication . Kalmakhanova, Marzhan; Díaz de Tuesta, Jose Luis; Massalimova, Bakytgul Kabykenovna; Gomes, HelderPillared clays with Zr and Fe/Cu/Zr polycations have been prepared from natural clays found in large deposits of Kazakhstan and assessed as catalysts for the catalytic wet peroxide oxidation (CWPO), using 4-nitrophenol (4-NP) as model compound. The performance of the catalysts was followed by measuring the concentration of 4-NP, H2O2 and the total organic carbon (TOC), considering C4-NP = 5 g L-1, CH2O2 = 17.8 g L-1, Ccat = 2.5 g L-1, initial pH = 3.0 and T = 50°C. At those selected conditions, the pillared clays showed higher activity than natural clays in the CWPO of 4-NP. The conversion of the model pollutant was complete when Fe/Cu/Zr-PILCs were used, with the TOC removal reaching 78.4% after 24 h with the best Fe/Cu/Zr-PILC. The H2O2, 4-NP and TOC time-evolution was well described by a kinetic model based on TOC lumps in three blocks, considering the initial TOC (corresponding to 4-NP), the production of oxidizable intermediates and the formation of refractory products.