18 research outputs found
The use of composite ferrocyanide materials for the treatment of high salinity liquid radioactive wastes rich in cesium isotopes
Several factors affecting the removal of cesium from LRW, namely total salt content, pH
and organic matter content, were also investigated. High concentrations of complexing organic matter
significantly reduced the sorption capacity of ferrocyanide sorbents
Development of a polymer composition to protect textile material from bio-damage
The article presents a method for increasing the microbiological resistance of textile materials under operating conditions. Studies were conducted using polyvinyl alcohol (PVA), maleic acid (MA) and a solution of silver ions (SI). This fabric was treated with an dressing composition to improve the antimicrobial properties of the textile material. In addition, research has been conducted to identify the physical and mechanical properties of samples treated with different concentrations of dressing composition, to prevent negative effects on the protection function and practicality of wear. The study revealed the most optimal concentrations of the composition components: PVA - 8 g/l, SI - 50 ml/l, MA - 5 g/l
Iodide removal by use of Ag-modified natural zeolites
In the present work Ukrainian clinoptilolite was modified with Ag and applied for the removal of iodide from aqueous solutions. The effect of three different modifications was studied, one resulting in an Ag+ ion exchanged form, and two resulting in zeolites decorated with silver oxide and zero valent metallic nanoparticles. The results indicated the strong potential affinity of the Ag-modified zeolite materials towards iodide
Nitrogen-grafted activated carbon for removing nitrate from water
Nitrate (NO3~) and nitrite (NO2~) ions are ubiquitous in the environment and considered
hazardous to humans. The primary health hazard from drinking water containing NO3~ occurs when it
is transformed to NO2~ in the digestive system (Robillard et al., 2006). Currently nitrate is removed from
water using polymer anion exchangers. However, this process is expensive and requires a lot of brine
(NaCl) for the exchanger regeneration. Alternative physicochemical methods such as reverse osmosis are
expensive and inefficient.
The proposed research aims to develop anion-selective nitrogen-containing activated carbon, NGAC
that can be regenerated electrochemically and does not require concentrated brine for regeneration. The
key to the selectivity of the NGAC is achieved by the deposition of N-bearing conductive polymers or
other species such as polypyrrole, polyaniline, pyridinium, quaternary ammonium, etc. onto the AC
surface. Our preliminary results indicate that the polypyrrole charge can remain stable through multiple
redox cycles (at least 50)
Research of camel shanks proteinhydrolyzates by electrophoregram
This research aims to study the degree of hydrolysis, determining the nature of protein hydrolyzates, which determine their size and molecular weight by the method of electrophoregram. In this research, a camel pancreas suspension was used to hydrolyze proteins from camel shanks. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was used to monitor the distribution of proteins and evaluate their molecular weights at different incubation times. Electrophoregram processing using the BioCapt program (Vilber Lourmat, France) determines the nature of the hydrolysis of protein and peptide profiles among hydrolyzates and the hydrolysis time for 8 hours shows the most significant accumulation of low molecular weight compounds with a molecular mass of <20 kDa, which is a favorable result for the potential activity of peptides
Investigation of rice husk derived activated carbon for removal of nitrate contamination from water
Development of porous carbons with high specific surface area (>1200mg−1) targeted at nitrate removal from aqueous solutions is investigated by chemical activation of carbonized rice husk. Potassium carbonate is used as activating and desilicating agent. The effect of post-synthetic treatment by gas phase ammoxidation with ozone/ammonia or oxidation with concentrated nitric acid followed by nitrification with urea on main physicochemical properties and on the effectiveness of the activated carbons in nitrate removal is compared with those determined for a pristine activated carbonized rice husk sample. The two-fold enhancement of nitrate removal by the urea-modified activated carbon in comparison with pristine and ammoxidated sample is in direct correlation with the development of surface basic groups
The Synthesis of Nanocomposites with Use of Cellulose
This work studied the synthesis of nanocomposites with cellulose use as crystallizing polymer on the basis of its ability to form crystalline particles with various parameters of an elementary cell – nanoparticles of a metal or oxide origin. The authors obtained high dispersed systems by dispersion of volume phases from solutions using condensation method. At using of this method, depending on the conditions of the formation process of the new phase can be obtained as systems with a size of several nanometers as well as more coarsely dispersed systems. The dispersiveness of a system, arising during formation of new phases, is determined by ratio speed of formation and nucleus growth of new phase a phase transition. The condensation process involves the formation of new phase according the heterogeneous or homogeneous mechanisms. The kinetics formation of new phase is determined by two stages: the formation of condensation centers (nucleus) and nucleus growth. In formation process of nanocomposite materials the natural polymer with known molecular structure is used as matrix, in which we can put desired nanoparticles in the form of filler. In this work the authors used cellulose which has developed capillary-porous structure, including in-fibrillar porous with the size of 1.5-10 nm, and which is able to form crystallites with different parameters of lattice cell
Determination of aspirin in municipal wastewaters of Nur-Sultan City, Kazakhstan
The presence of aspirin in the municipal wastewater of Nur-Sultan city, Kazakhstan, was studied in this research. Aqueous phase samples were collected before any treatment [1] and in the end of treatment process of Nur-Sultan wastewater treatment plant [2]. The study was conducted from April to December 2021. The concentrations of target compound were measured using high-pressure liquid chromatography (HPLC). The obtained results showed that the concentration of aspirin was generally higher than those reported in the literature. For instance, influent and effluent concentrations of aspirin were equal to 42.8 – 60.4 ppb and 1.4 – 6.5 ppb, respectively (October – December period). The removal of aspirin by wastewater treatment process was equal to 50 - 90.2%. Aspirin was not detected in the spring-summer period of 2021. This could be due to usage of aspirin as a medicine for the treatment and prevention of seasonal flu in the autumn-winter period by the population of the city of Nur-Sultan. Currently, our research team is working on investigation of other potential contaminants of emerging concern in municipal wastewaters of Nur-Sultan city and on treatment methods that could efficiently remove the contaminants of emerging concern
In situ functionalization of a cellulosic-based activated carbon with magnetic iron oxides for the removal of carbamazepine from wastewater
The main goal of this work was to produce an easily recoverable waste-based magnetic activated carbon (MAC) for an efficient removal of the antiepileptic pharmaceutical carbamazepine (CBZ) from wastewater. For this purpose, the synthesis procedure was optimized and a material (MAC4) providing immediate recuperation from solution, remarkable adsorptive performance and relevant properties (specific surface area of 551 m2 g-1 and saturation magnetization of 39.84 emu g-1) was selected for further CBZ kinetic and equilibrium adsorption studies. MAC4 presented fast CBZ adsorption rates and short equilibrium times (< 30-45 min) in both ultrapure water and wastewater. Equilibrium studies showed that MAC4 attained maximum adsorption capacities (qm) of 68 ± 4 mg g-1 in ultrapure water and 60 ± 3 mg g-1 in wastewater, suggesting no significant interference of the aqueous matrix in the adsorption process. Overall, this work provides evidence of potential application of a waste-based MAC in the tertiary treatment of wastewaters.publishe