Good Sorption Capacity Research Articles

Thermally stimulated desorption from the surface of black aluminum layers prepared by PVD methods

Black aluminum is characterized by a highly granular structure and porous surface - i.e. the real surface area is several times larger than its geometric projection to the substrate. In addition, it is a metal with good surface gas sorption capacity and structural stability up to temperatures T ∼500 °C.The surface exchange interactions between the ambient environment and thin layers of black aluminum prepared by different methods are described. These properties are convenient for materials that are suitable for the fabrication of active layers of chemiresistors. The layers were prepared by magnetron sputtering at room temperature and liquid nitrogen temperature, and evaporation with different compositions and gas flow rates. In this work, the process of thermally stimulated desorption was measured using mass spectrometry. The calculation of the activation energy Eact for the release of individual desorbing atoms, or radicals, from the surface of black aluminum was performed. Knowing of the temperature and the number of particles released by desorption allows us to get an idea of the number of defects and the functionalized structure of the surface layer.

Triethylene diamine-functionalized silver-activated charcoal for efficient, exothermic and spontaneous sequestration of radioiodine

ABSTRACT Efficient sequestration of radioiodine is one of the challenging tasks in nuclear establishment due to the radio-pharmaceutical applications as well as radiation release into environment point of view. In the present manuscript, an efficient and simple sequestration has been reported by triethylene diamine (TEDA)-functionalized Ag-activated charcoal, and the separation characteristics were compared to the virgin charcoal and Ag-activated charcoal. The kd values at 3 M HNO3 were found to follow the trend TEDA+Ag-activated charcoal > Ag-activated charcoal > charcoal. Pseudo-second-order kinetics was found to be predominating. Chemisorption involving Langmuir isotherm was operative with good sorption capacity (99.4 mg g−1). The sorption processes were found to be endothermic but spontaneous (ΔGTEDA+Ag activated charcoal~ −14.41 kJ mol−1, ΔGAg activated charcoal ~ -14.35 kJ mol−1 and ΔGActivated charcoal ~ -14.34 kJ mol−1). Though functionalization improved the separation efficiency, the radiological robustness was only moderate. Sodium thiosulfate as aqueous complexing agent was utilized for effective back extraction of iodine from loaded sorbents.

Ceramic Bowl‐Supported Nanofibrous Membrane with Fluorinated Silsesquioxane‐inspired Switchable Surfaces for Successive Crude Oil/Water Separation and Secondary Water Treatment

A simple, facile and economic approach was developed to transform a 2-tier hydrophilic biased electrospun hybrid PEBAX-FPOSS or Cabon/silica-FPOSS deposited on top of silica aerogel-exfoliated kaolinite ceramic, into hydrophobicity via a wetting switching mechanism subject to %FPOSS variance. Under the same wetting switching mechanism, we did transform originally hydrophobic expanded polystyrene (EP)-FPOSS into super-hydrophobicity with overriding good oil sorption and recovery capacity. Within 5%−10% FPOSS incorporation into PEBAX or Carbon/Silica, the consolidated hybrid membrane scaffold exhibited hydrophilic wettings with the capability not only to separate crude oil/water mixture but also to remove bacteria from both oil/water and polluted water. However, with 30–70% FPOSS blends via electrospinning, the system switched into hydrophobic/oleophilic wetting with the capability to separate crude oil/water in good performance. The hydrophilic electrospun hybrid membranes exhibited good performances in terms of water flux rate, organic rejection, and mechanical strength, which however is an index of %FPOSS incorporation. However, it became impossible to engage in gravity-driven filtration as FPOSS incorporation exceeded 70%.

Performance and mechanism of graphene oxide removal from aqueous solutions by calcite: adsorption isotherms, thermodynamics, and kinetics.

The flow of graphene oxide (GO) into natural water systems can adversely affect water environments and ecosystems. In this study, the adsorption effect of calcite on GO under different conditions was studied using calcite as adsorbent. Meanwhile, characterized by a combination of microscopic experiments, including SEM, TEM, XRD, FTIR, Raman, XPS, and AFM, additional research on the performance and the mechanism of GO sorption by calcite was conducted. The findings indicated that the highest adsorption efficiency was observed at a temperature of 303 K, pH 3, a mass of 90 mg of calcite, with an initial concentration of 60 mg L-1 GO, resulting in a 95% adsorption rate. The adsorption isotherm conformed to the model of Langmuir and Temkin, and it is a heat absorption process dominated by monolayer adsorption. The thermodynamic analysis showed that the adsorption was spontaneous and heat-absorbing. The adsorption kinetics conformed to the pseudo-second-order kinetic model, and the sorption procedure is chemisorption. In conclusion, calcite has a good sorption capacity for GO, which can provide a reference for the removal of GO in the aqueous environment.

Post-Modification of a Robust Covalent Organic Framework for Efficient Sequestration of 99 TcO4 - /ReO4.

Nuclear industry spent fuel reprocessing and some radioactive contamination sites often involve high acidity and salinity environments. Currently developed and reported sorbents in 99 TcO4 - sequestration from the nuclear waste are unstable and show low adsorption efficiency in harsh conditions. To address this issue, we developed a post-synthetic modification strategy by grafting imidazole-based ionic liquids (ILs) onto the backbone of covalent organic framework (COF) via vinyl polymerization. The resultant COF-polyILs sorbent exhibits fast adsorption kinetics (<5 min) and good sorption capacity (388 mg g-1 ) for ReO4 - (a nonradioactive surrogate of 99 TcO4 - ). Outstandingly, COF-polyILs composite shows superior ReO4 - removal even under highly acidic conditions and in the presence of excess competing ions of Hanford low-level radioactive waste stream, benefiting from the stable covalent bonds between the COF and polyILs, mass of imidazole rings, and hydrophobic pores in COF.

Double step heating synthesis of MIL-101(Cr) composites for water harvesting applications

Energy storage is a valuable mechanism for managing fluctuations in energy demand by allowing the distribution of energy production needed during peak demand over a more extended period. Thermal energy storage is among the most valuable categories of energy storage. The optimal sorbent material must satisfy thermal, physical, chemical, and environmental requirements for designing sorption heat storage systems. MIL-101(Cr) is a Metal-Organic Framework (MOF) with remarkable properties such as a high surface area, hydrothermal stability and good water sorbent capacity that make it a potential candidate as a working sorbent. Their physicochemical properties can be modulated by functionalizing the organic linker or by modifying its structure, improving the interaction with the target sorbate, mainly environmentally friendly and non-toxic sorbates such as water. However, good water sorption capacity is not the only characteristic to be considered when selecting the sorbent material for sorption heat storage systems. Here, we propose an alternative method to obtain a sorbent material with the objective of reducing the reaction time and achieving a good balance between the physical properties of the material, such as the density and the thermal conductivity, without substantially decreasing its water uptake capacity. For this aim, we show that structural modification of MIL-101(Cr) induced by CaCl2 and graphene oxide (GO) can improve the water sorption capacity and optical properties compared to the pristine sorbent. The MIL-101(Cr)/GO/CaCl2 composite had a higher water uptake capacity of 1.08 gwater g−1composite-1, even compared with MIL-101(Cr)/CaCl2 composite with a water uptake capacity of 0.68 gwater g−1composite. Additionally, MIL-101(Cr)/GO and MIL-101(Cr)/GO/CaCl2 sorbents tend to absorb light toward the near-infrared region and increase the temperature around twice as much compared to sorbents without GO when illuminated with a flash lamp. These results demonstrate that GO added at the MIL-101(Cr) structure allows a better distribution of CaCl2 in the MIL-101(Cr) pores and it may be advantageous in the water desorption process making use of renewable infrared radiation sources such as solar energy.

The effect of activator type on physicochemical and sorption properties of nanostructured carbon adsorbents obtained from fennel seed by chemical activation

AbstractIn this study, fennel (Foeniculum vulgare) seeds were used as a precursor for obtaining nanostructured activated carbons by chemical activation with various reagents. The obtained activated carbons were characterized using nitrogen adsorption–desorption isotherms, ash content, Boehm titration and pH of water extracts. It was shown that the choice of activator had an important effect on the physicochemical and sorption properties of the obtained activated carbons. The specific surface area of the obtained adsorbents ranged from 345 to 1052 m2/g. Chemical activation of the starting material with potassium carbonate made it possible to obtain activated carbons with the strongest developed specific surface area and the best sorption capacity against the tested pollutants. 1 g of this carbon is able to adsorb 1215 mg of iodine and 454 mg of methylene blue. The least effective adsorbent turned out to be the carbon obtained by chemical activation of fennel seeds with sodium carbonate, whose sorption capacity toward the pollutants from aqueous solutions was 77 mg/g and 317 mg/g for methylene blue for iodine, respectively. The alkaline pH of the solution promotes effective adsorption of methylene blue on the surface of the obtained adsorbents. The reaction of the dye molecules adsorption on the activated carbons occurs according to the pseudo-second-order model. The Langmuir isotherm best described the process under study. In addition, it was shown that chemical activation of fennel seeds leads to carbon adsorbents with acidic surface character. The negative values of Gibbs free energy indicate the spontaneous character of the process. The study has shown that fennel seeds can be successfully used to obtain low-cost and effective nanostructured carbon adsorbents with good sorption capacity toward organic and inorganic contaminants, from the aqueous phase.

Superhydrophobic polyurethane sponge modified with polydimethylsiloxane/ zinc oxide-rGO for efficient oil or organic solvent/water separation

Oil spills and oily industrial wastewater discharge have been the primary reasons behind numerous environmental problems. Herein, polyurethane sponge (PU) was modified by ZnO decorated rGO and polydimethylsiloxane (PDMS) to enhance the effectiveness to treat oily wastewater. The modified composite sponge showed superhydrophobicity (WCA ∼ 152.4˚), and good oil or organic solvent sorption capacity for n-hexane (20.88 ± 2.1 g/g), dimethylformamide (29.5 ± 2.6 g/g), turpentine oil (30.8 ± 1.9 g/g), diesel (32.4 ± 2.4 g/g), acetone (38.73 ± 1.05 g/g), toluene (41.6 ± 0.3 g/g), gasoline (42.2 ± 2.2 g/g), and cooking oil (42.5 ± 1 g/g) and good recyclability. It also showed good chemical stability (pH ∼ 3 to 9) and temperature resistance (50 ℃ to 200 ℃).

A stable microporous framework with multiple accessible adsorption sites for high capacity adsorption and efficient separation of light hydrocarbons

Metal-organic frameworks (MOFs), a type of designable porous materials, are effectively employed to realize light hydrocarbons storage and separation in favor of energy conservation and environmental protection, superior to traditional separation technology. Significantly, a novel MOF, Ni2(L)2(HCOO)2·4H2O (1) has been constructed from a bifunctional group ligand of 3-hydroxy-4-(4H-1,2,4-triazol-4-yl) benzoic acid ligand (HL). MOF 1 possesses stable porous structure with narrow channels functionalized with multiple accessible adsorption sites of hydroxy group, carboxyl oxygen atoms from the L− and HCOO−, exhibiting a well trade-off between good capacity and selectivity for light hydrocarbons. The single-component sorption isotherm results of Ni2+ based MOF not only shows good gas sorption capacity for light hydrocarbons of C2H2, C2H6, C2H4, C3H8, and greenhouse gas CO2, especially remarkable uptake for C2H2 (122.0 cm3 g−1 at ambient condition), but also favorable selectivity for binary mixtures of C2H2/CH4, C2H6/CH4, C3H8/CH4, C2H4/CH4, C2H2/C2H4 as well as C3H8/C2H6/CH4 ternary mixture, as confirmed by ideal adsorbed solution theory (IAST) calculations, and dynamic breakthrough experiment. Grand canonical Monte Carlo (GCMC) simulation reveals the multiple synergism of accessible adsorption sites including functional OH groups, carboxylate groups, HCOO− and π···π stacking interaction between guest molecules and host-pore are crucial to contribute selective gas adsorption of light hydrocarbons.

Optimization of Lead and Diclofenac Removal from Aqueous Media Using a Composite Sorbent of Silica Core and Polyelectrolyte Coacervate Shell.

The modification of inorganic surfaces with weak cationic polyelectrolytes by direct deposition through precipitation is a fast approach to generating composites with high numbers of functional groups. The core/shell composites present very good sorption capacity for heavy metal ions and negatively charged organic molecules from aqueous media. The sorbed amount of lead ions, used as a model for priority pollutants such as heavy metals, and diclofenac sodium salt, as an organic contaminant model for emerging pollutants, depended strongly on the organic content of the composite and less on the nature of contaminants, due to the different retention mechanisms (complexation vs. electrostatics/hydrophobics). Two experimental approaches were considered: (i) simultaneous adsorption of the two pollutants from a binary mixture and (ii) the sequential retention of each pollutant from monocomponent solutions. The simultaneous adsorption also considered process optimization by using the central composite design methodology to study the univariate effects of contact time and initial solution acidity with the purpose of enabling further practical applications in water/wastewater treatment. Sorbent regeneration after multiple sorption-desorption cycles was also investigated to assess its feasibility. Based on different non-linear regressions, the fitting of four isotherms (Langmuir, Freundlich, Hill, and Redlich-Peterson models) and three kinetics models (pseudo-first order (PFO), pseudo-second order (PSO), and two-compartment first order (TC)) has been carried out. The best agreement with experiments was found for the Langmuir isotherm and the PFO kinetic model. Silica/polyelectrolytes with a high number of functional groups may be considered efficient and versatile sorbents that can be used in wastewater treatment processes.

Effect of adsorption variables on the removal of Cadmium ions from wastewater using activated periwinkle shell from Okada, Edo State

This paper details the effect of adsorption variables on the removal of cadmium ions from wastewater using activated periwinkle shell. The periwinkle shells were carbonized for 1.5h for 900oC, and activated using HNO3 and calcium chloride solution. The textural characteristic of the adsorbent was determined using BET surface area analysis methods, structural characterizations of the activated carbon from the periwinkle shells were performed using FTIR, SEM, and EDX. Three different concentrations of cadmium ions solution were prepared as 10mg/l, 30mg/l, 50mg/l, 80mlg/l and 100mg/l from the stock solution. The batch mode adsorption experiment of cadmium ion onto activated periwinkle shell was carried out. The effects of time of contact, pH, initial concentration, adsorbent dose, particle sizes and temperature were investigated. The result indicates that activated periwinkle shell exhibit good sorption capacity with a large surface area of 574.50m2/g and mesoporosity of 71.42%. The sorption capacity were 67.28m2/g for Cd(II) ions. The equilibrium was attained after 70mins with the particle size of 212μm. The results indicate that the pH for maximum removal of cadmium (II) ions is 6.0.

A feasibility study for recycling biodegradable adsorbent in the oil spill clean-up from seawater

In the present work, the efficiency of Conocarpus leaves to remove oil from seawater was estimated. Conocarpus leaves were characterized by Brunauer–Emmett–Teller, scanning electron microscopy, Fourier-transform infrared spectroscopy and contact angle. The sorption parameters (sorption time, pH, oil ratio, biomass dose, initial oil concentration and temperature were investigated. The change in the pH of the oil/seawater system does not influence the oil sorption. Maximum oil sorption percent reached 88% at 2 min, 0.35 g at room temperature. The kinetic studies show rapid sorption and the pseudo-second-order kinetic governed the oil sorption. The isotherm modeling displayed that the oil uptake was fitted by the Langmuir isotherm. The outcomes of this work indicated a good sorption capacity (1.76 g/g) of Conocarpus leaves. In addition, Conocarpus leaves can be recycled for 4 cycles until the performance decays under 40%.

Characterization of Avocado (Persea americana) Seed Starch - Physicochemical and Powder Properties

Introduction: Starch is a biopolymer commonly used as an excipient in pharmaceutical formulations due to its biocompatibility, inertness, biodegradability, availability and affordability. Purpose: The study aimed to extract and characterize the starch isolated from avocado (Persea americana) seeds and investigate its disintegrant and binder properties in paracetamol tablet formulations. Methods: Starch was extracted from avocado seed using standard methods and then subjected to some phytochemical, physicochemical and bulk powder properties analyses. High-resolution analyses using differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and x-ray diffractometry (XRD) were also carried out on the extracted starch powder. Results: Starch extraction yield was 19.61% and the starch was light-brown in colour, odourless, tasteless and smooth in texture. The starch showed a melting point range of 102-114°C and moisture content of 22.7%. It also exhibited a hydration capacity of 2.76 g/g and swelling and moisture sorption capacities of 46.43 and 115.34%, respectively. The starch powder was cohesive with poor flow properties but the DSC, FTIR, SEM and XRD results showed a semi-crystalline powder composed of fluffy discrete particles. Conclusion: The starch isolated from P. americana seeds exhibited good swelling, hydration and moisture sorption capacities, making it a good candidate as a tablet disintegrant. Keywords: Avocado, starch, physicochemical, high-resolution, analyses

Влияние дрожжевых биосорбентов на качество вина

Foreign food industries know a variety of products derived from wine yeast cells. These products are used to improve the sensory properties of wine. This article describes the effect of a new yeast biosorbent on the sensory and physicochemical properties of white and red wine, e.g., their sorption capacity for heavy metals.&#x0D; The research featured red and white wines treated with the novel biosorbent. Glutarom (France) served as control. The study relied on various physicochemical, organoleptic, biochemical, and microbiological methods.&#x0D; The biosorbent affected neither the volume fraction of ethyl alcohol nor the mass concentration of sugars and titrated acids. However, the biosorbent reduced the mass concentration of volatile acids in terms of acetic acid: it decreased by 20% in the white wines and by 50% in the red wine samples. The mass concentration of the reduced extract decreased by 0.2–0.7 g/dm3 as the amount of sorbent increased. In the white wine samples, the protein concentration decreased by 1.5–1.8 times, while the concentration of polysaccharides decreased by 110–115 mg/dm3. The content of phenolic compounds decreased by 13–37%, depending on the amount of the sorbent, due to their condensed forms. The biosorbent reduced the value of the redox potential. The yeast sorbents effectively adsorbed metal cations, including those of heavy metals. A set of experiments also revealed the difference in sorption time for different metal cations. The effectiveness of the biosorbent was dose-dependent. The wines treated with the biosorbent had better sensory assessment results, especially the red wine samples. They had a soft, round, and harmonious flavor and a bright aroma with pronounced varietal tones.&#x0D; The novel biosorbent proved to have a good sorption capacity for phenolic compounds, as well as cations of toxic metals. It improved the sensory profile of the red and white wines. This biosorbent can substitute their imported analogs in the Russian wine industry.

Characterization of calcium bentonite to use as a natural barrier in a surface repository

The wide use of nuclear technology in Brazil generates radioactive waste that, in general, have low and medium levels of radiation. This requires efficient management to keep the environment, humans and future generations safe. CNEN coordinates the CENTENA project which will consist of the implementation of the first national repository that will be a definitive solution for the storage of radioactive waste. It will be surface and multiple barriers, and bentonite will possibly compose the natural barrier, since it has good sorption capacity for several radionuclides and low hydraulic conductivity. This paper describes the practical work that followed the clay characterization protocol for use in a surface repository with calcium bentonite and proposes a future study to characterize the mixture of soil and bentonite with the addition of 8% and 15% clay in the soil in order to investigate what will be the best feasible combination to maintain the safety and economic viability of the project. XRD results confirmed the presence of montmorillonite, particle size analysis identified that 40% of the measured sample had an average particle size between 8.0 and 10.0 µm, the global average bentonite moisture was 14%, the high specific surface area value 82.741m2/g, the particle density value was 2.5287 ± 0.0057 g/cm³ and the result of the cation exchange capacity by the methylene blue adsorption method was 750 ± 18.71 mmol.kg-1. All these results indicated that calcium bentonite is a good natural material to be used in the Brazilian repository.

Improved fertilization efficiency of manure compost obtained by using oil shale semicoke as the bulking agent

Oil shale semicoke is a kind of solid waste produced during the retorting process of oil shale, which could cause environmental pollution without reasonable disposing. In our previous study, the abandoned semicoke was recycled as bulking agent to reduce the nitrogen loss and greenhouse gases emission during composting. But influences of the obtained semicoke-blended compost on soil properties and plant growth remained unclear, which would be discussed in this study. Through leaching experiments, it was found that the N/P/K retention capacity of soil mixed with semicoke-blended compost significantly increased for the good nutrients sorption capacity of oil shale semicoke. Subsequently, germination test showed the germination index of semicoke-blended compost could attain 120%, implying its low phytotoxicity. And pot experiments exhibited the biomass of cress and Brassica rapa significantly increased by 2–4 times when applying semicoke-blended compost as fertilizer, exhibiting its great benefits to plants. For the increase of crop yield, it was closely related to their elevated nutrients uptake efficiency, also might be related to the improved soil microbial community and activity as the microbial analysis indicated. Finally, results of pollutant detection showed the concentration of polycyclic aromatic hydrocarbons, Cr, As, Cd and Pb in the mature semicoke-blended compost obtained through composting was 2.82, 95.30, 5.95, 0.34 and 14.45 mg kg−1 respectively, meeting the standard for soil application. The research suggests composting could be an effective method for the harmless disposing and resource recycling of oil shale semicoke waste.

The reduction of the As and Pb phytotoxicity of a former mine technosol depends on the amendment type and properties

In remediation of metal(loid) polluted soils, it is crucial to improve soil conditions and reduce metal(loid) toxicity to permit plant growth. To do that, amendments, such as biochar, activated carbon, and redmud, can be applied to the soil. Their effects are dependent on their type and properties. The aims of this study were thus to evaluate the potential of diverse biochars, activated carbons, and redmuds to reduce phytotoxicity of a former mine technosol polluted with As and Pb. Two pots experiments were set up. The first one applied on Pontgibaud technosol ten biochars, eight activated carbons, and three redmuds, at 2% for the biochars and activated carbons and 1% for the redmud. Soil pore water properties (pH, electrical conductivity), metal(loid) mobility, and Phaseolus vulgaris growth were monitored. In a second experiment, the five best amendments, one redmud associated with two biochars and two activated carbons, selected based on their ability to improve soil conditions, immobilize metal(loid)s and improve plant growth, were applied. The same plant species was used and soil and plant parameters were measured. Results demonstrated that not all amendments were capable of ameliorating soil conditions and reducing soil phytotoxicity. Moreover, the five selected amendments (biochars from oak bark sapwood and bamboo, activated carbons from vegetal feedstock chemically activated and physically activated, modified redmud) showed good sorption capacity towards Pb, with maximum sorption capacity between 63 and 217 mg g−1, depending on the amendment, and their combined application led to better soil properties improvement than the single amendments. However, plant growth was only ameliorated further than a single application in the redmud-biochar combination but not in the association of redmud with activated carbon. This study is one of the first to deliver a rapid phytotoxicity test screening demonstrating that redmud associated with particular biochar could be beneficial in reducing the phytotoxicity of technosol polluted with As and Pb and thus allow plant growth and a phytomanagement process.

Role of Zeolite Structural Properties toward Iodine Capture: A Head-to-head Evaluation of Framework Type and Chemical Composition

This study evaluated zeolite-based sorbents for iodine gas [I2(g)] capture. Based on the framework structures and porosities, five zeolites, including two faujasite (FAU), one ZSM-5 (MFI), one mesoMFI, one ZSM-22 (TON), as well as two mesoporous materials, were evaluated for I2(g) capture at room temperature and 150 °C in an iodine-saturated environment. From these preliminary studies, the three best-performing zeolites were ion-exchanged with Ag+ and evaluated for I2(g) capture under similar conditions. Energy-dispersive X-ray spectroscopy data suggest that Ag-FAU frameworks were the materials with the highest capacity for I2(g) in this study, showing ∼3× higher adsorption compared to Ag-mordenite (Ag-MOR) at room temperature, but X-ray diffraction measurements show that the faujasite structure collapsed during the adsorption studies because of dealumination. The Ag-MFI zeolites are decent sorbents in real-life applications, showing both good sorption capacities and higher stability. In-depth analyses and characterizations, including synchrotron X-ray absorption spectroscopy, revealed the influence of structural and chemical properties of zeolites on the performance for iodine adsorption from the gas phase.

Hydrophobic and fire safe polyurethane foam coated with chitosan and nano-montmorillonite via layer-by-layer assembly for emergency absorption of oil spill

Considering the fire risk associated with absorbent materials in emergency disposal of oil spills, we coated polyurethane foams with chitosan and nano-montmorillonite via layer-by-layer assembly technology and modified them with polydimethylsiloxane to obtain a hydrophobic surface. The coated foams exhibit good oil sorption capacity, high selectivity for oil–water separation and recyclability. The cone calorimeter and thermogravimetric analysis results reveal that the coating can reduce the flammability and improve the thermal stability of PU foams. Moreover, the coated foams with more bilayers exhibit higher oil absorption capacity, flame retardancy and thermal stability. This work prepares a promising material with less fire risk for emergency oil absorption.

Assessment of the influence of the composition of the soil-sludge mixture for the reclamation of disturbed lands on the content of oil products and heavy metals

The article considers a method for the disposal of drill cuttings for the reclamation of disturbed lands. The soil and sludge mixture for restoring disturbed lands is oil production waste, sand and peat mixed in a given ratio; if necessary, sorbents and oil flora destructors can be added. The authors conducted an information search for raw materials that are used for the industrial production of oil sorbents on the Russian market. Vermiculite used in this work is a natural sorbent and biostimulant. In order to evaluate the contribution of each of the added components to the properties of the resulting soil-slurry mixture and to select their optimal ratio, an experiment planning matrix was compiled. The authors have shown that in terms of physical and chemical properties, soil-slurry mixtures with different content of components meet the requirements for reclaimed lands. Unremediated drill cuttings, when sludge pits are overfilled or destroyed, or simply improperly stored without arrangement, lead to an increase in environmental pollution with oil and oil products, heavy metals and other chemicals. As a result of the research, regression equations were obtained for the sorption of oil products and lead ions depending on the content of peat, sand and vermiculite. It was shown that the content of sand in the soil-slurry mixture has the greatest effect on the absorption of oil products, while a change in the amount of peat and vermiculite has little effect on the content of oil products in the soil. The content of lead ions is most affected by the amount of vermiculite introduced; peat also showed good sorption capacity for lead in the composition.