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This work is based on a detailed study of samples from three industrial bentonite deposits in Russia (10th Khutor, Zyryanskoe) and Kazakhstan (Taganskoe). The samples of the listed bentonites were undergoing stage-by-stage purification from carbonates, organic matter, and non-clay iron-bearing phase procedures. The conducted research revealed changes in the composition of bentonites already at the first stage of purification, which, however, were not noted for all bentonites, as well as a change in the forms of Fe in smectite structure. The latter is probably associated with changes in cis- and trans-vacant positions. Sorption characteristics with respect to 137Cs are determined using the localization and charges in the smectite layer and the slight changes during purification, along with the specific surface area indicators. [ABSTRACT FROM AUTHOR]

Students acquire various skills in the laboratory through scientific development practices such as demonstrations and experiments. The primary objective of this study is to gather empirical data regarding the implementation of organic compound separation and purification techniques at tertiary educational institutions to examine their efficacy as a proactive step to facilitate ongoing educational endeavors. The elements discussed include the practicum topics completed, the organic chemistry instruments and equipment possessed, how the practicum is conducted, and the problems and their resolutions. This study's respondents included course instructors, chemistry lab assistants, and students previously attending practicum content. This study used a qualitative research methodology to analyze multiple chemistry education study programs across various locations in Indonesia. Data collecting methods include open-closed surveys, observation, and documentation. The findings indicated that the separation and purification practicum topic incorporates concepts related to separation and purification, employing extraction, chromatography, distillation, sublimation, and recrystallization techniques. Some chemistry education programs needed adequate instrumentation for organic chemistry. In addition, the wet laboratory practicum for separating and purifying the studied organic compounds are yet to be completed as per the planned topics. Green chemistry and project-based learning have been largely implemented in the practicum, but the micro-scale concept, which can help reduce practicum waste, are yet to be implemented. Inadequate tools and materials for the practicum, as well as inadequate reference materials, are some of the obstacles that hinder the practicum's efficiency. Hence, there is a want for pragmatic instruments that can effectively cater to the demands of ongoing education. This practicum set should facilitate using green chemistry and micro-scale, focusing on minimizing pollution that can harm the environment. [ABSTRACT FROM AUTHOR]

Current trends have been noticed in to study of unedible parts of food as sources of phytochemicals or as ingredients in order to develop new uses for discarded materials and to promote sustainability. This study aimed to evaluate the performance of six macroporous resins (XAD 16, XAD 7HP, XAD 2, XAD 4, DAX 8, and XAD 1180 N) in purification of phenolic compounds from organic purple‐fleshed sweet potatoes. Static adsorption and desorption showed that XAD16 and XAD7HP had the highest adsorption and desorption ratio and recovery yield. The process temperature did not affect the adsorption capacity of XAD16. However, XAD7HP showed higher adsorption capacity when performed at 30°C, compared with 40 and 50°C. The process of equilibrium adsorption isotherms for phenolics was better described using Freundlich isotherm model. Dynamic adsorption process on XAD7HP resin showed that phenolic compounds in the water extracts of leaves started to break through after 4.5 bed volumes of extract was loaded. The purification of phytochemicals using adsorption is an alternative to replace organic solvents and provide a safety process for industrial application. Practical Applications: Recently, phenolic compounds have been explored due to their significant biological and antioxidant properties; phenolic compounds are also related to decreasing the risk of cardiovascular diseases, cancer, oxidative stress, diabetes, fatness, cancer, and several degenerative diseases. In addition, there is the potential use of phenolic compounds such as anthocyanin as safe colorimetric pH indicators in innovative packaging due to the relationship between levels of pH and anthocyanin colors. Therefore, using advanced processing technologies, phenolic compound purification can be essential for many applications related to food safety, quality, nutrition, and food waste. Furthermore, purified phenolic compounds can be used as raw materials in the pharmaceutical area and food industries. [ABSTRACT FROM AUTHOR]

The crude glycerol produced as a byproduct of transesterification synthesis has very few applications because it comprises of significant amounts of methanol, catalyst, and soap. On the other hand, transesterifications of highly acidic oil in the presence of an alkaline catalyst are problematic due to the presence of high amounts of free fatty acids. In this study, the free fatty acid level of high acid oil, which was initially determined to be 19.25%, was decreased to permit the direct production of biodiesel via glycerolysis with pure glycerol, making direct transesterification feasible. Through a process of purification, crude glycerol was refined to 92.5% purity. It was revealed that the physiochemical parameters of density, moisture content, ash content, matter organic non-glycerol content, pH, and Na/K concentrations of generated purified glycerol are equal to those of commercially available glycerol. In contrast, glycerolysis treatment successfully decreased the free fatty acid level to less than 2% under optimal conditions, which were determined to be 200 °C, a glycerol-to-oil molar ratio of 4:1, and a KOH catalyst concentration of 1.6 wt.% at 350 rpm. The inclusion of hexane as a co-solvent accelerated the glycerolysis process, and the weight ratio of oil-to-hexane was 8:1. Moreover, it was viable to use waste methanol for biodiesel synthesis and purified crude glycerol as a raw material in a variety of industries, including biodiesel production. In addition, compared to acid esterification, the FFA concentration of oil with a high acid value fell significantly. [ABSTRACT FROM AUTHOR]

Copyright of Egyptian Journal of Experimental Biology (Botany) is the property of Egyptian Society of Experimental Biology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ability of locally laboratory-synthesized polyaluminium chloride (PAC) with high Al13 content (PAC-Al13) to remove organic, inorganic matter and colour from potable water, agricultural and electroplating wastewaters was evaluated relative to commercial PAC (PACI). PAC-Al13 used in this study was prepared using batch titration of NaOH into AlCl3·6H2O solution under vigorous stirring as opposed to the conventional slow-base titration method. The highly pure PAC-Al13 (containing 79% polymeric Al13 species) with high basicity (87%) was isolated and extracted using the sulphate displacement method and metathesis reaction. PAC-Al13 showed higher COD (85–96%), metals (95–100%), TDS (86–90%) and colour (90–95%) removal compared with PACI, i.e. COD (57–74%), metals (71–99%), TDS (58–80%) and colour (85–92%). The dominance of polymeric Al13 species in PAC-Al13 was supported from the scanning electron microscopy images (presence of Keggin structure of Al13) and the 27Al nuclear magnetic resonance analysis that showed the appearance of a single peak at 62.1 ppm. This study demonstrated the potential of using a new type of PAC, produced using simple preparation technique and contain high polymeric Al13 species, that has the ability to remove contaminants from water and wastewater systems more efficiently. [ABSTRACT FROM AUTHOR]

Copyright of Journal de Ciencia e Ingeniería is the property of Corporacion Universitaria Autonoma del Cauca and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents a novel hydrophobic material based 9-octadecenoic acid grafted graphene (POG) for oil/water separation. Graphene derived from graphite was modified with 9-octadecenoic acid to obtain 9-octadecenoic acid grafted graphene (OG). Then, emulsion polymerization of styrene was performed on OG to produce polystyrene branches on 9-octadecenoic acid grafted graphene (POG). Synthesized POG composites were then characterized by using various tools. The separation performance of the composites was evaluated by using an emulsion of organic compounds such as heptane with dye-colored water. Three different composites were prepared by varying the amount of 9-octadecenoic acid grafted graphene used as follows: POG 25 , POG 50 , and POG 75. The results showed that the higher the ratio of the 9-octadecenoic acid grafted graphene, the higher the oil uptake efficacy of the material and the faster the rate of the adsorption. The material was regenerated and its performance was tested again. The adsorption rate was constant for the next several cycles. Thus, this material has the potential to be utilized to clean up oil spills or to remove oil contaminants from water for cleaner production of produced water. • Polystyrene branched 9-octadecenoic acid grafted graphene is reported. • It showed excellent performance for the removal of oil from water. • The material showed recyclability with constant adsorption rate for several cycles. [ABSTRACT FROM AUTHOR]

Abstract A simple, effective, easy-handling and reliable method for recycling of [18O]H 2 O from fluorine-18 production, was developed based on co-precipitation, co-crystallization and distillation. Preliminary experiments with normal H 2 O were used to determine the optimal purification conditions, which were tested for purification of used [18O]H 2 O from a scientific and commercial 18F-production facility. The obtained recycled [18O]H 2 O had comparable quality to commercially available 18O enriched water. The loss of weight for enriched water was about only 7% and losses of 18O enrichment about 1.3% ± 0.2%. The method ensures elimination of radioisotopes (99.7% ± 0.1%), organic compounds (99.5% ± 0.1%) and trace metals (99.8% ± 0.1%) with special attention on radiation safety with dosimetry control checks and in total 1000 times mass reduction of the initial radioactive waste. Highlights • Simple method for recycling of irradiated 18O-enriched water with optimized procedure for reducing the radiation burden by eliminating all radioactive contaminants as a first step in the process. • Organic compounds, radioisotopes and trace metals are eliminated by high-yield processes included in this method such as co-precipitation, co-crystallization and distillation. • The method demonstrates effective purification ability in a wide range of concentrations of organic solvent impurities from ppm to percentage. • A new method for purification of previously irradiated enriched water for volumes less than 100 ml> is developed. • The method ensures elimination of radioisotopes (99.7% ± 0.1%), organic compounds (99.5% ± 0.1%) and trace metals (99.8% ± 0.1%) with special attention on radiation safety and generated radioactive waste. [ABSTRACT FROM AUTHOR]

Background. Tannic acid is a chemical compound belonging to the Tannins phenolic compounds, which are complex organic compounds with a carbohydrate structure and are found in a wide range of plants. These compounds are causing intensive initiation of multiple functions such as metabolism. Tannic acids might be playing the role of oxidation antagonists. Under the conditions of directly application on the surface of the skin tannic acids are preventing cold-induced sores, might be used against fever, blisters, diaper rash, impetigo, minor burns, and sunburn. They might be used to treat poison by iv infections, sore throats, tonsillitis, thinning gums, and ingrown toenails. However, more data are needed for clinical proofs of such effects. The aim of the work was purification of tannic acid from pomegranate peels for further evaluation of its binding abilities with phosphorus containing compounds. Materials and methods. The rude fraction of pomegranate peels was isolated from the fruit and sliced for further homogenation. Affinity-chromatography methods for purification of tannic acid were developed. Tannic acid sephadex G-50 conjugates- beads were serving for the affinity chromatography of phosphorus containing compounds. Results and conclusion. We established the new method of tannins purification. It was developed the affinity chromatography method based on the high affinity of albumin to tannins. Tannic acid molecules were easily detached during affinity chromatography by the eluent and were present in the highest concentration in the first fraction of collection. We also, created the affinity gel for the binding of the phosphorus containing molecules. Based on our investigations, 90 % of the phosphates from applied amount were binding with the tannic acid carrying gel. [ABSTRACT FROM AUTHOR]

An experimental study on obtaining concentrates of organic compounds from fuel fractions of petroleum by complexation with metal halides: aluminum chloride, aluminum bromide, anhydrous zinc chloride, and its crystal hydrate has been performed. Optimal conditions have been selected for the complexation reaction of aluminum and zinc halides with electron-donor compounds of diesel and jet fuels. The degree of removal of organic sulfur compounds from the diesel or jet fuel by complexation with aluminum chloride reaches 79.6 or 10.0 rel. %, respectively. It has been found that the concentrates obtained contain a large amount of normal and weakly branched alkanes, which form clathrates with polar components of the donor-acceptor complex (DAC). A mechanism is proposed for the intermolecular interaction of alkanes with the DAC components by hydrogen bonding with halogen, oxygen, and sulfur atoms. [ABSTRACT FROM AUTHOR]

Organo-sepiolite (OSep) is conventionally prepared by two main steps, including purification of sepiolite (Sep) and organic modification procedure. These two steps were completed independently by two factories or production lines. In order to save more water, energy, cost and decrease polluted water, a one-step method to purify and organically modify Sep was proposed. Orthogonal test was used to optimize the conditions. X-ray diffraction demonstrated three impurities, i.e., quartz, calcite and talc, were include in the raw ore. The mass content of Sep in raw ore was 30%. By this one-step method, the crystalline impurities were completely removed. Organic modification did not influence on the crystal structure and morphology of Sep. The organic surfactant was not only used as organic modifier, but also used as flocculant, making OSep was easier to be separated from the dispersion. Zeta potential results demonstrated that dispersant increased the negative charges of Sep surface, enhancing the repulsive force between Sep. And the surfactant destroyed the electrical double layers and decrease the surface negative charges. Surfactant cations were adsorbed on the surface of Sep, resulting in hydrophobic surface. Contact angles and gel volumes indicated the compatibility between OSep and oil. The one-step method could not only purify Sep, but also efficiently modified the surface properties. This procedure is simple, environmentally friendly and cost saving, with high efficiency. [ABSTRACT FROM AUTHOR]

In order to properly determine the future wastewater utilization, this study assesses the physicochemical characteristics of removed water from microwave heating of Inner Mongolia lignite with various microwave powers. The chemical oxygen demand (COD), NH3 -N, TP, pH, inorganic anions, inorganic cations and organic compounds were, respectively, analyzed. Moreover, the activated carbon, ultrafiltration membrane and NaOH solution were adopted to purify the wastewater. Results showed that microwave heating could effectively remove the lignite moisture and upgrade the coal rank. The pH of removed water was acidic and decreased with microwave power. The COD content first decreased and then increased with the peak of 509 mg/L due to the combination of organic release rate and water removal rate. All the detected cation concentrations were below 1 ppm and anion concentrations were below 10 ppm. The organic compounds in the removed water mainly consisted of polar organics, heterocyclic organics, aromatic hydrocarbons and aliphatic hydrocarbons. Therein, polar organics took up the majority, mainly alcohols and esters. The removed water quality almost got to the proper point, except for the pH and COD. After relevant purification, the acidic wastewater was neutralized and the COD contents were all below 60 mg/L, the industrial water reuse criteria. [ABSTRACT FROM AUTHOR]

The effect of a reverse osmosis concentrate recirculation on the mineral and organic compounds in a landfill leachate was investigated. Investigated was the quality of a leachate from two landfills operated for different periods (a 20-year-old Cell A and a 1-year-old Cell B), where the concentrate was recirculated. Examined were general parameters (conductivity, pH), organic compounds (biochemical oxygen demand (BOD), chemical oxygen demand (COD), total organic nitrogen, BOD/COD), and inorganic compounds (nitrogen ammonia, sulfite, sulfate, cyanide, boron, chloride, ferrous, zinc, chrome, copper). The findings from the first year of investigation showed that over the initial period of recirculation, the concentration of organic compounds (BOD, COD) increased, but after 6 months their values stabilized. It indicates that the concentrate recirculation accelerated organic decomposition, especially in the new landfill Cell. The analysis of inorganic parameters showed that recirculation landfills produce a leachate with a higher concentration of N-NH, and Cl. In case of the old landfill Cell, an increase in B and Fe was also noticeable. These compounds are cyclically washed out from a waste dump and require an additional pretreatment in order to exclude them from recirculation cycle. The increased concentration of Cu, Zn, and Fe was noticed during the initial months of recirculation and in the season of intense atmospheric precipitation in the leachate from both Cells. Higher values of electro conductivity, Cl, N-NH, B, and Fe in the leachate from the old field indicate that the attenuation capacity of this landfill is close to exhaustion. [ABSTRACT FROM AUTHOR]

Mixed mode or multimodal chromatography has been developed for rational use of multiple interactions in a controlled manner, in contrast to non-specific interactions. Indeed, as the term “mixed mode” suggests, these resins allow different types of interactions within a single chromatographic medium. In this paper, HEA HyperCel™, PPA HyperCel™ mixed-mode chromatographic media have been studied. These mixed-mode sorbents typically involve hydrophobic pseudo-affinity interactions for binding and essentially ionic interactions (charge repulsion) for elution. We identified and characterized these different interactions in chromatographic experiments by exploiting specific properties of proteins using protein standards and complex mixtures. We highlighted the major intervention of at least two types of interactions in these media: hydrophobic and electrostatic interactions. We observed the behaviour of these resins at different pH, ionic strength, with different salts and buffers types and in the presence of different organic compounds. [ABSTRACT FROM AUTHOR]

Volatile organic compounds (VOCs) are found in indoor air, and many of these can affect human health (e.g. formaldehyde and benzene are carcinogenic). Plants affect the levels of VOCs in indoor environments, thus they represent a potential green solution for improving indoor air quality that at the same time can improve human health. This article reviews scientific studies of plants' ability to remove VOCs from indoor air. The focus of the review is on pathways of VOC removal by the plants and factors affecting the efficiency and rate of VOC removal by plants. Laboratory based studies indicate that plant induced removal of VOCs is a combination of direct (e.g. absorption) and indirect (e.g. biotransformation by microorganisms) mechanisms. They also demonstrate that plants' rate of reducing the level of VOCs is influenced by a number of factors such as plant species, light intensity and VOC concentration. For instance, an increase in light intensity has in some studies been shown to lead to an increase in removal of a pollutant. Studies conducted in real-life settings such as offices and homes are few and show mixed results. [ABSTRACT FROM AUTHOR]