Physicochemical and Sorptive Properties of a Phosphorylated Mercerized Cotton Fabric

A process of phosphorylation for a mercerized cotton kersey fabric was investigated. After wet oxidation, the phosphorus content in each sample was determined by spectrophotometric analysis. The range was 0.179 to 0.950 mmol g–1. A significant decrease in the tensile strength of samples resulted from an increase of phosphoric acid concentration in the phosphorylating solution. The mercerization has a positive impact on the process of phosphorylation, as the phosphorus content was found to be three times higher in the samples that underwent mercerization. The sorption properties of phosphorylated cotton fabric were studied using the Cu2+ sorption process as a reference. The value of the static exchange capacity for the phosphorylated fabric was determined to reach its maximum when the concentration of the H3PO4 in the phosphorylating solution was 1.40 M, and was found to be 1.48 ± 0.11 mmol g–1 with the phosphorus content equal to 0.898 ± 0.090 mmol g–1. The sorption of Cu2+ by a single phosphorus-containing group occurred for samples with phosphorus content not exceeding 0.80 mmol g–1. The preliminary studies of micro-quantities of 241Am, 233U, and 239Pu radionuclide sorption from aqueous solutions with phosphorylated textile demonstrated the high efficiency.

Sorption And Physicochemical Properties of A Phosphorylated Mercerised Cotton Cellulose

A process of a mercerised cotton cellulose sample phosphorylation has been investigated. After oxidation a phosphorus content was determined by spectrophotometric analysis and it was in a range of 0.179 to 0.950 mmol g–1. A significant decrease in the tensile strength of the sample was found upon an increase of phosphoric acid concentration in a phosphorylating solution. Phosphorylated mercerized fabric contents more phosphorous as unmercerized fabric in 3 times. The sorption properties of phosphorylated cotton cellulose in aqueous solution containing Cu2+ were characterized. The maximum of static exchange capacity was found to be 1.48 ± 0.11 mmol g–1 for phosphorylated cotton with content 0.898 ± 0.090 mmol g–1 of phosphorus. The sorption of Cu2+ by single phosphorus-containing group occurs for samples with not exceeding 0.80 mmol g–1 of phosphorus. The preliminary studies of uranium(VI) micro quantities of radionuclides 241Am, 233U and 239Pu sorption from aqueous solution with phosphorylated textile demonstrated the high efficiency.

The development of technology for production of zeolites from fly-ash from Troitskaya power plant

The study examines the technology of processing fly ash from Troitskaya power plant for the production of zeolite. The paper presents the results of laboratory studies evaluating the suitability of fly ash from Troitskaya power plant for the production of zeolites and the development of the zeolite production process. Fly ash contains a small amount of heavy metals that can complicate processing, but contains a large amount of silicon oxide. The technology consists of high-temperature alkaline activation of fly ash and hydrochemical synthesis. The resulting powder has a specific surface area of 89.7 m2/g, determined by the BET method, and an average pore diameter of 0.345 μm. The static exchange capacity was 220 mg/g.

SYNTHESIS AND INVESTIGATION OF THE CHELATING ION EXCHANGERS BASED ON COPOLYMERS OF EPOXYACRYLATE

The possibilities of obtaining new chelating (complexing) ion exchangers based on copolymers of glycidyl methacrylate (GMA), methyl methacrylate (MMA), tripropylene glycol diacrylate (TPGDA), and oxyethylenediphosphonic acid complexone (OEDP) were studied. The optimal synthesis conditions and studied the physicochemical properties of the resin.To assess the acid-base properties of the synthesized polyelectrolytes, potentiometric studies were carried out, it was determined that the new ion exchangers have a medium acid character, and also belong to polyfunctional ion exchangers. The structure of the synthe-sized ion exchangers GMA-TPGDA-MMA: OEDP, GMA-MMA: OEDP was established by IR spectroscopy and elemental analysis. Studied the influence of the ratio of the initial reacting components, temperature and duration of the process on the static exchange capacity of ion exchangers. It was found that an increase in the amount of oxyethylenediphosphonic acid in the initial mixture in the reaction mixture from 1.0 to 3.0 mass parts leads to an increase in the capacity from 4.3 mEq / g to 6.2 mEq / g according to GMA-TPGDA- MMA: HEDP, from 4.8 mEq / g to 6.6 mEq / g according to GMA-MMA: HEDP. The chemical stability of the ion exchan-gers showed that the obtained ion exchangers are quite inert to chemical reagents. The most stable was the cation exchanger based on the ternary copolymer GMA-TPGDA-MMA: HEDP with a mass ratio of 1: 3. The degree of loss of capacity of the ion exchanger, obtained on its basis, does not exceed 9% when treated with solutions of acids, alkalis, and under the action of oxidizing agents, SEC practically does not change.

SYNTHESIS AND RESEARCH OF CHELATE FORMING SORBENT BASED ON CARBAMIDE, FORMALDEHYDE, DITIZONE

The purpose of this study is the synthesis and study of a chelating sorbent for the extraction of ions of non-ferrous and noble metals. To achieve this goal, a sulfur-containing chelating sorbent based on carbamide, formaldehyde, and dithizone was synthesized and studied. The optimal conditions for the synthesis of the sorbent have been determined and studies have been carried out on the influence of the molar ratios of the starting materials on the composition, and physicochemical properties of the synthesized sorbent. The optimum temperature of polycondensation was taken as 90 °C, the reaction time is 2.5-3 hours, as a result, the reaction is more uniform and the exchange capacity for a 0.1 N HCl solution reaches 3.8 mg-eq/g. As a result of the studies carried out, the sorbent with the best performance was obtained at a 1: 2: 0.5 ratio of carbamide, formaldehyde, and dithizone, respectively. Based on the results of IR spectroscopy, the reaction of sorbent formation is proposed. The static exchange capacity of the synthesized sorbent for metal ions was determined, mg-eq/g: Cu (II) – 2,75; Zn (II) – 2,83; Ni (II) – 2.72; Ag (I) – 3.12

Sorption Extraction of Strontium Radionuclides from Surface Water by Natural Aluminum Silicate

The contamination of large volumes of surface waters with radionuclides is caused by the appearance of a significant number of objects that pose a potential radiation hazard. The search and development of affordable, environmentally friendly sorbents for the purification of such waters is an urgent task, the solution of which will make it possible to propose effective measures for the purification of natural water bodies from pollution. The article presents the result of research of sorption reduction of 90Sr radionuclide from aqueous solutions with experimental samples under static and dynamic conditions. Methods. We have defined the strontium concentration range within which the reduced component distribution between solid and liquid phases obeys Henry law. The granulated sorbent distribution index in the Henry area was Kd=(3.46±0.2)•102 ml/g in terms of strontium and this is comparable with the Kd=200 ml/g value of the initial natural glauconite. The obtained value of the sorbent static exchange capacity in terms of strontium in the (10-5 – 1) g/l concentration range is ≥ 4.2 mg/g. We investigated the sorption kinetics in the recirculation mode. We have presented the output curves of the strontium sorption with the developed sorbent in the dynamic mode. The strontium distribution index was at least 2.42 ∙ 103 ml/g and this approximately 10 times exceeded the value obtained under the static conditions. After passing of 900 column volumes of the model solution through the column, no compacting of the sorbent was observed and this confirmed preserving of its hydro/dynamic characteristics and the possibility to use it as a filter loads in ant water treatment systems. Results. The sorbent produced from local mineral raw material is applicable and feasible for use in treatment of the Ural region water bodies contaminated with 90Sr. We have demonstrated good perspective of the natural aluminum silicate glauconite of the Karinsk deposit (Chelyabinsk Oblast, Russia) granulated with bonding tap water use as a sorbent for extraction of strontium radionuclide from natural waters in the process of radioactive-contaminated territories.

RESEARCH OF SORPTION CAPACITY OF CUTTING WASTE OF URBAN TREES IN RELATION TO DISSOLVED PETROLEUM PRODUCTS IN AQUATIC ENVIRONMENTS

The article considers main problems associated with the treatment of surface wastewater in urban areas. This work addresses the task of searching for methods of extraction from aqueous solutions of petroleum products related to the main contamination of surface wastewater. Shredded waste from urban trees filing is an economical sorption material. Urban trees’ sawdust solves the problem of recycling tree branches. The authors describe of the experimental determination of oil capacity and static exchange capacity of maple and poplar sawdust, and show a dependence of the degree of extraction of oil products by phytosorbents on the contact time. The article concludes with assessment of applying urban trees filing waste as a sorption filters’ filling for cleaning surface wastewater from oil products.

SYNTHESIS AND PROPERTIES OF ION EXCHANGERS DERIVED FROM NON-WOOD CELLULOSE

A rational scheme for the processing of large-scale agro-industrial waste – walnut shells Juglans Regia L. and apricot kernels Prunus Armeniaca L. was proposed. At first stage, the raw material was delignificated using liquid ammonia to remove hemicelluloses and lignin. Isolated non-wood pulp is chemically modifying to increase sorption and ion exchange properties. For the synthesis of anion exchangers, cellulose was aminated using pyridine or trimethylamine after preliminary treatment consequentially with formalin and C2H5OH in HCl medium. As a result, we obtained high and weakly-basic ion exchangers with nitrogen content of 10.3–11.5% and high exchange capacity towards various classes of inorganic anions. For synthesis of cation exchangers, cellulose was treated with solution consisting of 20% H3PO4, 40% CO(NH2)2, and 40% H2O. Consequently, we obtained phosphorus-containing high-acidic cation exchangers with exchange capacity towards heavy metal of 5.5–8.6 mmol∙cm–3. Both types of ion exchangers have a high capacity towards uranium: anion exchanger – 4.25 mmol∙cm–3 and cation exchanger – 4.94 mmol∙cm–3, respectively. Average total yield of ion exchangers related to weight of air-dry feedstock was 90%. Synthesized ion exchangers characterized by IR spectroscopy. Presence of amine functional groups –NH2 in aminated cellulose and phosphate ester groups –OPO(OH)2 in phosphorylated cellulose was established. Specific surface area and total static exchange capacity of synthesized ion exchangers were established. An environmentally friendly method for the disposal of spent solutions from the synthesis of cation exchangers was proposed. It allows getting a liquid complex fertilizer containing 17% N and 13.9% P2O5. Usage of this fertilizer for grain crops feeding increases plants length by 40–75%, as well as overall biomass increase by 20–30%.

Sorption of nickel (II) and manganese (II) ions from aqueous solutions

Mine water from non-ferrous metal deposits is often contaminated with nickel and manganese ions. The entry of these ions, especially nickel, into surface waters and underground aquifers is undesirable since it has a negative effect on living organisms and worsens the condition of drinking water sources. One of the promising methods for selectively extracting nickel ions and obtaining an eluate suitable for further use is sorption by weakly acid cation exchangers with chelate groups of iminodiacetic acid. As part of the study, sorption isotherms of nickel and manganese ions by Lewatit MonoPlus TP 207 cation exchanger in mono- and bicomponent systems were obtained. In monocomponent systems, the maximum static exchange capacity (SEC) of the cation exchanger for nickel ions is 952 mmol/dm3, and in bicomponent systems – 741 mmol/dm3; for manganese ions– 71 mmol/dm3 and 49 mmol/dm3, respectively. It is obvious that the studied cation exchanger has a greater capacity for nickel ions than for manganese ions. The influence of a temperature increase from 300 to 330 K on the sorption of nickel and manganese ions was established: in monocomponent systems, the maximum degree of extraction of the former increases from 65 to 77 % (SEC from 337 to 399 mmol/dm3), and the latter from 21 to 35 % (SEC – from 140 to 229 mmol/dm3); in bicomponent systems, the extraction of nickel ions increases from 59 to 78 % (SEC – from 307 to 429 mmol/dm3), and manganese ions decreases from 20 to 17 % (SEC – from 164 to 131 mmol/dm3). The predominant increase in the indicators is due to the filling of the sorption centers of the ion-exchange resins, which are energetically unfavorable for the exchange of counterions at a lower temperature. The influence of the pH of the solution on sorption was determined: the intensification of the process for nickel ions is observed in the pH range of 8.0-8.5 in a monocomponent solution and 8.0-9.0 in a bicomponent solution, for manganese ions in the range of 8.0-9.5 in both cases. The increase in the degree of extraction of ions and the exchange capacity of the ion exchanger with increasing pH is associated with the appearance of singly charged hydroxocations, dissociation of the functional groups of the sorbent and, to some extent, with the subsequent formation of insoluble forms of nickel and manganese. However, with increasing pH, a decrease in the selectivity of nickel extraction is observed: the ion separation coefficient decreases from 14.0 to 6.0 in the pH range of 6.0-11.0.

Study of Sorption of Manganese (II) Cations by Composite Sorbent

A significant increase in the amount of pollution (including heavy metals) that enter the hydrosphere as a result of human activity, sanitary requirements that are imposed on the quality of water, lead to the search for effective ways and methods of its purification. Wastewater from many industrial plants contain heavy metal salts, including manganese compounds. The sorption of manganese (II) cations by a composite sorbent from model solutions under static conditions was studied, to determine the possibility of using this sorption material in wastewater treatment. The characteristics of the sorption capacity of the composite sorbent are determined. It was established that the static exchange capacity of the composite sorbent is 0.9 mg/g; distribution coefficient - 47.34 l/g; the degree of purification of the solution is 99.9%. The empirical sorption equations for the manganese (II) cation are found, the sorption isotherms are constructed. It is established that the sorption process is described by the Freundlich equation. Experiments have shown that the composite sorbent is effective in extracting manganese (II) from aqueous solutions. Experimental data suggest that the sorbent studied can be used to clean industrial wastewater from manganese compounds.