Glass Column Research Articles

Lipase-Mediated Synthesis of Oleoyl Ethanolamide Starting from High-Oleic Sunflower Oil Soapstock

This work describes the lipase-mediated synthesis of oleoyl ethanolamide, a dietary supplement for body weight loss recently approved by FDA. The target compound is prepared by conversion of the oleic acid contained in a mixture of fatty acids recovered by enzymatic hydrolysis of soapstock, a side-product of high oleic sunflower oil refinement. The use of a packed-bed reactor (a glass column loaded with the commercial lipase Lipozyme 435) in continuous flow mode improves the space-time yield of the reaction and the catalyst productivity. The nontoxic, bioderived, and renewable solvent limonene is used in the reaction medium. The process has been run for more than 157 h of continuous operation, demonstrating the stability and efficiency of the biocatalyst. Additionally, at the end of the reaction, only oleoyl ethanolamide crystallizes from the reaction mixture, thus, it is collected by simple filtration of the outlet solution in 53% isolation yield, showing 99% chemical purity, while all the byproducts of the reaction are left behind in the mother liquors.

Continuous fixation of dissolved arsenite from flooded soil by cooperating ferrihydrite with Geobacter sulfurreducens

The fixed arsenic in soil is easy to be released into the aquatic environment in the form of arsenite (As(III)) with high toxicity and mobility due to the eutrophication of environment under anaerobic conditions. However, As(III) is difficult to be fixed in situ continuously by traditional methods, especially for the most efficient fixation method by iron ores. Based on that Fe(II) could promote the fixation of As(III), this study investigated the possibility that Geobacter sulfurreducens (G. sulfurreducens) cooperates with ferrihydrite to fix released As(III) from flooded soil in a glass column continuously under anaerobic conditions. During 42 days of operation of reactors that simulated the actual flooded soil environment, the concentration of released As(III) in the reactor with adding G. sulfurreducens and ferrihydrite is always lower than that in reactors with adding ferrihydrite or no treatment. Compared with reactors without treatment, the accumulated content of released As(III) (2455.0 ± 313.1 μg) decreased by 39.4% in the reactor with adding G. sulfurreducens and ferrihydrite on the last day, while that in reactors with adding ferrihydrite only decreased by 11.6%, respectively. These were caused by the cooperation of G. sulfurreducens and ferrihydrite, which increased the relative abundance of iron-reducing microorganisms to inhibit metabolisms of As-reducing microorganisms, inhibited the quick release of As(III) from solid soil, and promoted the release of iron to accelerate the formation of stable secondary ores with As. This study could provide an environmentally friendly method to fix dissolved As(III) pollutants from soil continuously.

Monitoring workability properties of self-compacting concrete (SCC) using Internet of Things (IoT)

Workability, determines whether the concrete is suitable to cast in-situ for specified job. In practice it is determine by multiple test methods to find the workability properties by following EFNARC guidelines. To evaluate these properties in single test Ultrasonic sensors (hc-sr04) and Ultrasonic pulse velocity (UPV) test are used. The float glass box of dimensions 300×300×400 mm with reinforcement inside 16mm dia with spacing 46mm and clear cover 40mm is used for simulation. The hc-sr04 sensors are placed at the corners of the glass column for determining the concrete filled into the box and monitor through Arduino.ide software. The filling ability is determined by the time taken to fill the column and classified into FA1, FA2 & FA3 classes. The passing ability is determined by the difference of concrete height at inside the reinforcement and at the corners after filling and classified into PA1, PA2 & PA3. Ultrasonic velocity measurements are taken by direct mode and based on the variations at different locations segregation resistance is classified into SR1, SR2 & SR3. The aim of this simulation was to establish the relation between experimental tests and simulation IoT test results. Comparison between empirical tests and stimulation model shows that this model can used to check the workability at in-situ to meet the job specification.

Processes for the Clarification of the Crude Oil of Baobab Seeds Extracted by Pressing on Activated Carbon Elaborated from the Capsules of the Fruit (<i>Adansonia digitata</i> L.)

The baobab, Adansonia digitata L. plays an important role in the economy of local populations. The oil from the seeds of the baobab fruit is nowadays highly prized because of its numerous cosmetic and therapeutic applications and its composition of unsaturated fatty acids, sterols and tocopherols. However, unlike refined oils, locally extracted baobab oil has not undergone purification operations to ensure its quality. Only a filtration on special cloths is carried out after decantation. Indeed, the oil obtained after pressing is cloudy because of the presence of various impurities. It therefore requires treatment operations to make it more attractive and of higher quality. Therefore, in order to provide innovative solutions to local companies to improve the quality of vegetable oils, a study of clarification (treatment) of crude oil is necessary. An experimental device has been developed in the laboratory. It includes a glass column and a filter bed of dune sand and activated carbon. This study has shown the efficiency of the experimental device. Indeed, the activated carbon, thanks to its adsorbing power, has allowed a significant decrease in turbidity at the 5% threshold, from 14.61 NTU for the raw oil to 0.08 NTU for the oil filtered on 3% carbon and 0.033 NTU for the oil filtered on 5% carbon. That is to say an abatement higher than 95%. This decrease in turbidity could be correlated with the decrease in brown index from 187.39a for the initial crude oil to 128.53d for the oil treated with 3% activated carbon versus 187.59a for the oil filtered on cloths. The lowest brown index was observed with the filtration using 5% activated carbon (35.99b). Thus, for the yellowness index, only the filtration on 5% charcoal allowed to obtain a significant decrease in yellowness. The yellowing index of the oil with 5% was 44.67b against 79.04a for the oil filtered with 3% activated carbon, 86.33a for the crude oil and 86.46a for the oil filtered on cloths. Finally, the oil sample treated with 5% activated carbon had the clearest clarity than the other samples with a clarity (L) equal to 97.98c against 95.63d for the oil treated with 3% carbon and 94.99b for the oil filtered on filter cloths. According to the results obtained, the experimental device made it possible to obtain a clearer baobab oil with a low brown index, thus improving the sensory quality of the oil.

Light Fatty Acid Methyl Esters in Biodiesel Derived from the Gueiroba (Syagrus oleracea) Kernel Oil to Blend with Jet-A1 Kerosene for Aviation Fuel

The approach proposed here is focused on the separation of light fractions (corresponding to fatty acids with molecular chains between 8 to 14 carbons) from the fatty acid methyl esters (FAMES) of the biodiesel obtained by the reaction of transesterification of triacylglycerol’s in the kernel gueiroba oil (Syagrus oleracea) with methanol. The whole biodiesel was fractionated through atmospheric distillation in a single glass column with thermal insulation. Such a separation produced 59.79% in volume of light biodiesel (LB), which was mixed with the standard mineral Jet-A1 kerosene (cf. ASTM, corresponding to the QAV-1, cf. the Brazilian standard of the ANP) for aviation, in the volumetric ratios LB:Jet-A1 2:98; 5:95; 10:90 and 20:80. The values of density, water content, distillation analysis, flash point, calorific value and freezing point were carefully checked for their compliance with the official recommendations for a jet fuel. It was found that the mixtures richest in the Jet-A1 mineral kerosene, that is, those containing no more than 5% LB by volume, well meet the recommended standards and are technologically viable to replace pure Jet-A1 kerosene for the propulsion of turbine aircraft.

Adsorptive bubble separation method in the recovery of a biomolecule

AbstractThe present work aims to separate an amino acid (l‐phenylalanine) from a highly dilute aqueous solution by the ‘adsorptive bubble separation method’. Separation is based on the principle of adsorption at the interphase of the gas bubble and aqueous phase and subsequent amino acid extraction in the top layered nonaqueous phase. The operation was carried out in a long glass column with a comprehensive solvent chamber at the top. Design‐Expert software optimizes the process parameters, and the process involves three variables: gas (nitrogen) flow rate, extractant, and solvent quantity, which control responses, recovery percentage, and the ratio of enrichment. The design models are found to be significant. The maximum recovery of amino acid observed was 75.545% and the value of the enrichment ratio was 3.87. In addition, two models were generated by the software, which was statistically significant (P < 0.05). Therefore, this process is adopted as it is of straightforward construction, eco‐friendly, and less costly than other methods previously known to recover l‐phenylalanine from a dilute solution. © 2022 Society of Chemical Industry (SCI).

Hydrometallurgical Recovery of Copper Tailing Waste by Bioleaching at Hindustan Copper Limited, India

The conventional methods of refining cannot be implemented for recovery of copper from tailing waste collected from Hindustan Copper Limited, Khetri, India as it contains low copper and higher iron along with other metals present. Hence bioleaching was tested as an alternative approach for the recovery of copper from the waste. The study investigated the feasibility of using a bioleaching process for the treatment of copper tailing waste. The XRD and ED-XRF analysis confirmed that the waste contained 0.13% w/w copper, which is present in different forms including chalcopyrite (CuFeS2). Shake flask studies optimized with tailing concentration, optimum temperature, and pH showed 94.03 % w/w recovery of copper at 2 % w/v waste concentration after 40 days of exposure at pH 2.0. The study was extended to a pilot-scale glass column filled with raw copper tailing mixed with Acidithiobacillus ferrooxidans at a flow rate of 3 L h-1. A recovery of 54.71% w/w of copper was obtained by this setup. The mix-proportion clay bricks were cast with the tailing waste after bioleaching. The bricks showed better compressive strength as compared to normal bricks. A pilot scale heap leaching study with 5 kg of tailing waste mixed with Acidithiobacillus ferrooxidans showed a 64.28% w/w copper tailing in 40 days.

Individual Compounds of <i>Rhodoila quadrifida</i> Rhizomes and Roots: Isolating and Establishing Structure

Introduction. Medicinal plant raw materials, containing a wide range of various biologically active compounds, are of considerable interest as a likely source of new, pharmacologically active biologically active substances. One of the promising plants is Rhodiola quadrifida (Pall.) Fisch. & C.A. Mey, since the raw materials contain phenolic compounds and their derivatives, which cause anti-inflammatory, antioxidant and anticarcinogenic effects. In addition, this plant has considerable popularity in folk medicine as a dietary supplement.Aim. Isolation of individual compounds from rhizomes and roots of Rhodiola quadrifida and subsequent determination of their structure by NMR and mass spectrometry for phytochemical profiling.Materials and methods. Rhizomes and roots of Rhodiola quadrifida, purchased in the pharmacy of St. Petersburg (place and time of procurement according to the information on the package – Altai (near Barnaul), in March 2019. The ethanol extract fractions (ethanol, hexane, butanol, and water) obtained during sequential liquid-liquid extraction were examined on a LC-20 Prominence instrument (Shimadzu, Japan) with an SPD-M20A diode array detector to determine the chromatographic profile. The most promising ethyl acetate fraction was purified by column chromatography on open glass columns with sorbents of different selectivity and preparative chromatography [Smartlina (Knauer, Germany)] with a spectrophotometric detector. The structure of the obtained individual compounds was determined by NMR (Bruker Avance III 400 MHz, Germany) and confirmed by low-resolution mass spectrometry [Flexar FX-15 (PerkinElmer, USA)].Results and discussion. During the study, 7 individual compounds were isolated from the rhizomes and roots of Rhodiola quadrifida, namely 3,4-dihydroxybenzoic acid, 4-hydroxybenzoic acid, caffeic acid, ethyl gallate, catechin, epicatechin and tyrosol. These compounds were isolated for the first time from the raw materials of Rhodiola quadrifida. They are the major compounds and can characterize the phytochemical profile of raw materials, as well as determine the direction of pharmacological activity.Conclusion. For the first time, Rhodiola quadrifida was isolated from raw materials and the structure of 7 majority compounds was proved by NMR spectroscopy and mass spectrometry, which can serve as a foundation for further study of this species of Rhodiola and targeted study of its pharmacological activity in vitro and in vivo, considering the individual phytochemical profile.

To Optimize Sequencing Batch Reactor (SBR) and Monitor Aerobic Granular Sludge (AGS) Development for Domestic Wastewater Treatment

The aim of this study is to determine design and process parameters of the aerobic granular sludge system to treat actual domestic wastewater. The aerobic granular sludge was developed in a 2.5 L lab-scale bioreactor which uses the operational system based on the sequencing batch reactor (SBR). The bioreactor was fed with influent from local sewerage treatment plant and seeding with fresh inoculums (seed sludge) from activated sludge tank. The operation of the reactor was based on the SBR system with a complete cycle time of 4 hours and specifically designed to be operated for 24 hours continuously. Two sets of experiments were carried out in a single-walled cylindrical glass column bioreactor. These two sets of experiments are referred to as SBRA and SBRB with different time setting. SBR systems have four stages which is feeding, aeration, settling and decant. It was carried out in sequence: (1) ‘feeding with aeration’ for SBRA (feed and aerate pumps operated simultaneously); ‘feeding without aeration’ for SBRB (feed and aerate pumps operated separately), (2) ‘aeration only’, (3) ‘settling’, and (4) ‘discharge’. Removal performance of the SBR such as BOD, COD, AMN, NO3−, TSS, VSS and TP along with the other several parameters of the SBR such as DO, SOUR, ORP and settling profile are monitored daily. Starting from day 1 until day 26 the average DO values were around 1 - 2 mg/l but after 1.5 hours the DO values increased drastically. It shows that the microbe did not consumed air during the process. Day 13 onwards SOUR profiles show that the microbe consumed oxygen slowly. These results suggest that low amount of readily oxidized organic available in the bioreactor. The SVI reading shows good settling performance which is less than 100 mL/g. The settling profile shows the sludge has been further compact day by day. From the finding, it is suggested that it would be better for feed and aerate pumps to be operated separately.

The effect of silver-containing sorbent on red blood cells during hemosorption: an <i>in vitro</i> study

The aim of the study was to investigate the influence of the original porous silver–containing sorbent on the morphofunctional parameters of red blood cells during in vitro hemoperfusion. Material and methods. Donor blood was perfused through glass columns filled with a sorbent based on porous aluminum oxide, polydimethylsiloxane and silver nanoclusters and a sorbent without silver. The effect of a silver-containing sorbent on the change in morphofunctional parameters of red blood cells after perfusion through sorbents was determined by scanning flow cytometry. Results and their discussion. Due to the uniformity of the distribution of silver (0.1 %) over the sorbent granules, the parameters of the porous structure – the specific surface area and pore volume – practically do not change compared to the sorbent without silver. Morphological parameters of original donor blood and after hemoperfusion are within the norm. The functional parameters are also normal, although the introduction of silver in to the sorbent slightly increases the number of active band 3 (B3) proteins on erythrocyte membranes, both in comparison with the donor red cell mass as a control and in comparison with the sorbent without silver. There is also an increase in the ultimate extensibility of the erythrocyte membrane compared to the original blood (2.2 times) and the sorbent without silver (1.4 times). Conclusions. A sorbent modified with silver and a sorbent without silver does not have a damaging toxic effect on the morphofunctional parameters of blood under perfusion conditions. The mechanisms affecting the indicators of the ultimate extensibility of the erythrocyte membrane after blood perfusion through a silver-containing sorbent require further research.

Surfactant-free air bubble flotation-coagulation for the rapid purification of chloroquine.

A simple and rapid separation method based on surfactant-free air bubble flotation and coagulation was designed for the purification of chloroquine (CQ) from its crude product. An open glass column having a sintered glass filter (for column chromatography) was used as a flotation vessel. The flotation was conducted by pouring the crude CQ into the aqueous solution containing 0.1% (v/v) of 2-propanol followed by feeding air through the glass filter to generate air bubbles. At pH 12, CQ was enriched into the foam temporary generating on the surface of water to form the coagulates within 90s after the start of the air bubble flotation. On the other hand, reactants; 4,7-dichloroquinoline and 4-amino-1-diethylaminopentane, as well as generated impurities remained in the bulk aqueous solution. The result of dynamic surface tension measurement indicated that CQ molecules selectively adsorbed on the air-water interface and the coagulates more strongly adsorbed the interface. Adsorption and coagulation of CQ molecules on the air-water interface were also reproduced in the calculation results of a molecular dynamic simulation. The coagulates were collected from the surface of water by suction and then poured into another flotation vessel for conducting repeated separation. The time required for the respective separation process including air bubble flotation and collection by suction was within 5min. After three-times separation, highly purified (> 99.0%) CQ was obtained with a yield of 72 ± 8%. The amounts of reactants and other impurities reduced into undetectable levels.

STUDY OF THE OZONE REACTION OF BENZYL ACETATE AND ITS DERIVATIVES IN THE LIQUID PHASE

Purpose. Investigation of the kinetic regularities of the oxidation reaction of benzyl acetate and its derivatives by ozone in the liquid phase to determine the effect of alcohol on the ozonation of methylbenzenes by the methyl group.
 Methodоlogy. A 20 ml glass vessel equipped with a magnetic stirrer was loaded sequentially with a calculated amount of toluene or benzyl acetate of sulfuric acid and 10 ml of acetic anhydride. After dissolution, the reaction components were loaded into a thermostatic glass column. The column was connected to a reflux condenser, the resulting solution was cooled to the required temperature and ozone-containing gas was passed through it. Oxidation was carried out to a given degree of substrate conversion. The process was controlled by gas-liquid chromatography. The ozone concentration in the gas phase was determined spectrophotometrically on an SF-46 spectrophotometer. The concentration of toluene and its derivatives in the solution was determined by gas-liquid chromatography on the chromatograph with a flame-ionization detector on the column with a length of 1 m and a diameter of 3.5 mm, filled with a carrier – INERTON-Super (0.16–0.2 mm), with a fixed phase “FFAP” applied to it in the amount of 5% of the mass of the carrier under the following conditions: evaporator temperature is between 503–533 K; carrier gas velocity (nitrogen) – 2.0 L•h-1; hydrogen velocity – 1.8 L•h-1; air velocity – 18 L•h-1. Thermostating was carried out in the temperature range of 363–448 K, the temperature rise was carried out by the program - 8оC/min.
 Findings. The kinetic parameters of the ozonation reaction of benzylacetate and its derivatives in the liquid phase were studied. The rate constants of ozone reaction with benzyl acetate at different temperatures and the influence of the structure of substituents on its reactivity were determined. It is shown that the presence of electron-acceptor substituents increases the selectivity of oxidation along the side chain to 54%, and electron-donor – to a decrease of up to 8%. The kinetics of the reaction of ozone with benzyl acetate at a temperature of 293 K is described by a second-order equation that assumes a non-chain oxidation mechanism. At elevated temperatures, the chain consumption of ozone becomes noticeable due to its reaction with the products of destruction of the aromatic ring.
 Originality. For the first time, the kinetics of the oxidation reaction of benzyl acetate and its substituted ozone in the liquid phase, which significantly affects the equilibrium concentration of alcohols in the oxidation of the corresponding methylbenzene. It was found that depending on the structure of acylated benzyl alcohol, the oxidation selectivity along the side chain is from 8 to 54%. The reaction rate constants are determined and the mechanism of ozonation of benzyl acetate is proposed, which will allow optimizing the parameters for the development of technological bases for the production of benzyl alcohol and its derivatives by ozonation of methylbenzenes in the liquid phase.
 Practical value. The results are the basis for the development of low-temperature method for the synthesis of benzyl alcohols used in the production of active pharmaceutical ingredients.

Separation of heavy metals by amino acid functionalized polymer: Experimental and theoretical insights

A chloromethylated polystyrene resin was chemically functionalized with glycine molecules to introduce metal ions chelating sites. The functionalized resin (PsGly) was loaded in a glass column and successfully used for the extraction of heavy metal ions. Several experimental parameters like solution pH, sample flow rate, adsorbent dose and breakthrough volume was studied and optimized. The adsorption capacity observed for Ni(II), Cu(II) and Zn(II) were 0.72, 0.68 and 0.60 mmol g−1, respectively. The chelating mechanism for metal ion adsorption was studied by density functional theory. The metal-ligand interaction energy, entropy, and Gibbs energy were estimated by employing the B3LYP basis set of density functional theory and suggest that the studied metal ions form strong complexes with the adsorbent. The column procedure was employed for the extraction of heavy metal ions from wastewater with detection limit of 0.2 μg L−1.

Sand-Based Economical Micro/Nanocomposite Materials for Diverse Applications.

Sand is one of the most fundamental construction materials that is of significant importance and widely used for making concrete, plasters, and mortars, and also for filling under floor and basements. Sand-derived functional materials, for instance superhydrophobic sand, which can be used to prepare liquid marble, separate oil-water mixtures, and transport liquids, have recently been a highly topical and promising research field. However, such materials are mainly prepared using valuable surface modification agents via complicated procedures that are difficult for mass-production, which restricted their true applications. Here, we developed a simple, low-cost, and efficient method for the development of sand-based hierarchical micro/nanostructured composite materials with diverse applications. Briefly, micro/nanostructured superhydrophobic sand was synthesized by one-step in situ growth of a network layer of silicone nanofilaments on the surface of sand microparticles, using only one cheap chemical of small molecules of silanes. The as-prepared superhydrophobic sand displays excellent performance in waterproofing, water storage, soil moisturizing, and oil-water separation. Furthermore, sand-supported micro/nanocomposite catalysts were obtained through covalent attachment of polyamines on the surface of silicone nanofilaments. Such composites, packed in a glass column, were used as a simple flow reactor for Knoevenagel condensation reactions. Quantitative amounts of pure products without further purification can be obtained in such a simple way that just allowing the reactants solution flows through the composite catalysts driven by gravity. These results pave the way toward the development of sand-based multifunctional materials with great potential for industrial use, given their versatile functions and excellent performances but easy-to-fabricate, low-cost preparation procedure.

Calcium Silicate As A Media For Enhancement of Vitamin E Concentration from Candlenut Oil (Aleurites moluccana)

Vitamin E consists of two parts, namely tocopherol and tocotrienol which are found as minor components in candlenut oil. The process of increasing vitamin E concentrate in candlenut oil aims to obtain higher vitamin E levels from candlenut oil through a major and minor component separation with adsorption and desorption methods with three types of calcium silicate hydrate adsorbent namely calcium silicate with 90% absolute ethanol (Ca-S 90), calcium silicate with 75% absolute ethanol (Ca-S 75) and calcium silicate synthesized from CaO (Ca-S). The three adsorbents were synthesized by hydrothermal method at 170ºC for 24 hours accompanied by stirring and characterized by XRD, SEM-EDX, and BET. Furthermore, the adsorbent was applied to enrich vitamin E concentrate in candlenut oil through the adsorption process using a glass column with a mass ratio between candlenut oil and adsorbent that was 1:1, then the vitamin E desorption process was carried out by adding n-hexane solvent. Vitamin E levels obtained after the adsorption and desorption process were for Ca-S 75 adsorbent was 764.41 ppm (1. 82 times enriched), for Ca-S 90 adsorbent was 1011.29 ppm (2. 40 times enriched) and for Ca-S adsorbent was 1029, 38 ppm (2.4 5 times enriched) from the initial vitamin E level in candle nut oil was 420.66 ppm. Ca-S adsorbent showed the best vitamin E enrichment.

Construction of a domestic wastewater disinfection filter from biosynthesized and commercial nanosilver: a comparative study

PurposeBiosynthesis of nanoparticles is an eco-friendly process and considered one of the most significant aspects of nanotechnology. Silver nanoparticles (Ag NPs) have a better bactericidal activity due to its high surface area to volume ratio. In this paper, Streptomyces sp. U13 (KP109813) was used to biosynthesize silver nanoparticles (Ag NPs) to construct wastewater disinfection filter.MethodsThe biosynthesized nanosilver and a commercially available ink nanosilver were characterized, and their wastewater disinfection efficiency was compared. The nanometrological characteristics of both nanosilver such as structure, shape, and size were investigated using the X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FTIR), high-resolution transmission electron microscope (HR-TEM), and UV-visible spectroscopy.ResultThe results revealed that the biosynthesized and ink Ag NPs were well dispersed and had a spherical shape, with sizes ranged from 5 to 37 nm and from 2 to 26 nm, respectively. To examine the disinfection capabilities, Ag NPs were loaded on two substrates, foam and limestone gravel, and packed into a glass column receiving domestic wastewater. Results showed that Ag NPs attached to limestone gravel eliminate 100% of the coliform bacteria better than foam. Comparing to control columns (without silver), only 50 and 10% reduction of the total coliform in gravel and foam column were achieved, respectively.ConclusionThis work concluded that the type of substrate controls the amount of Ag NPs loaded on it and thus controls the disinfection process. No significant difference between biosynthesized and ink nanosilver in wastewater disinfection was observed. Using limestone gravel filter loaded with 200 mg/l Ag NPs with contact time of 150 min achieves a complete eradication of coliform bacteria.

Fixed‐bed column adsorption of methyl orange by poly(vinyl pyrrolidone)‐functionalized manganese oxide

AbstractBACKGROUNDFixed‐bed column adsorption provides a practical approach for decontamination of wastewater from toxic azo dyes. A novel water‐stable poly(vinyl pyrrolidone)‐functionalized manganese oxide hydrothermally prepared for methyl orange azo dye adsorption is reported.RESULTSSurface studies of the composite were conducted using scanning electron microscopy, Fourier transform infrared spectroscopy, X‐ray diffraction and surface area analysis. The surface area of the composite (113 m2 g−1) was greater than that of plain metal oxide (108 m2 g−1). The point of zero charge was calculated using the salt addition method. A continuous flow of methyl orange was carried out in a 40 cm long glass column under different operating conditions determining the breakthrough curve and the breakthrough point time. Experiments were carried out as a function of initial dye concentration (10–30 mg L−1), bed height (0.6–1.5 cm) and rate of flow (5–20 mL min−1) from the column at constant temperature and pH.CONCLUSIONSThe saturation time increases from 700 to 3500 min with increase in bed length. The saturation time decreases from 2000 to 400 min with an increase in initial dye concentration. Similarly, when the flow rate is increased the saturation time and dye adsorption are reduced and the breakthrough curve becomes steeper. The adsorption data were evaluated using the Thomas model to calculate maximum adsorption at various flow rates and the Yoon–Nelson model to identify exactly the saturation point, confirming that the rate of reaction increases with increasing flow rate. © 2022 Society of Chemical Industry (SCI).

Incorporating steel-industry waste in water based drilling fluids for hydrogen sulfide scavenging

Drilling formations with hydrogen sulfide (H2S) pockets causes significant corrosion and operating issues for drilling equipment, as well as exposes working personnel to health and safety risks. Steelmaking, on the other hand, is an energy-intensive process that generates enormous amounts of waste, which is difficult to manage both economically and environmentally. Therefore, the objective of this study is to assess the possibility of using steel industry waste as an H2S scavenger in water-based muds. The H2S scavenging capacity was evaluated for the base mud and fluids containing commercialized SourScav® and steel-waste. The scavenging capacities were calculated using the H2S concentrations measured at the glass column's outlet after contact with the fluid sample. Also, the effects on drilling fluid rheological and filtration properties were investigated, and the corrosion rate was identified for the prepared fluids. According to the experimental results, utilizing steel-waste improved the base mud's H2S scavenging capability by 61%, compared to 50% with the SourScav at the required pH for drilling applications in sour environments. Incorporating steel-waste also raised the plastic viscosity and yield point by 16 and 9%, respectively, and improved the gelling structure with higher gel strengths. Furthermore, adding steel-waste reduced the filtrated volume by 25% with less potential formation damage and a slight reduction in composed filter cake thickness and weight, whereas the SourScav-composed filter cake characteristics were preferred, with weight and thickness reductions of 20 and 22%, respectively. Steel-waste and SourScav both had non-corrosive effects, with corrosion rates of less than 0.9E-5 lb/ft2. By exploiting and recycling steel industry waste, this study delivers an innovative and low-cost H2S scavenger that aids in waste management and, thus, the decrease of negative environmental and economic repercussions of these wastes.

Comparison of Behaviour of Laminated Banister Panels with Embedded Connections

Glass became a very popular building material in recent decades. Modern architecture often works with glass facades, roofs, banisters or columns. However, using glass elements in structures may be problematic due to glass elements connections. The connection must bear all stresses arising during the lifetime period and meet high aesthetical standards at the same time. Various bolted and adhesive connections were developed in order to achieve as transparent look as possible. The embedded laminated connection combines mechanical and adhesive fixing systems. The ongoing research at the Faculty of Civil Engineering of the CTU in Prague is focused on the characteristics of this type of connection. Within this research, two sets of real-scale laminated banister panels with the embedded connection were tested. The first set included the samples consisting of two 8 mm glass plies bonded with two layers of an EVA foil. The second set of samples consisted of one 10 mm glass ply and one 6 mm glass ply also bonded with two layers of an EVA foil. There was one pair of embedded steel countersunk bolts with HDPE liners in each of the lower corners. A short-term vertical load was applied on the samples. During the experiment, stresses and deflections in several points were measured. The experiments showed the collapse mode and a short-term resistance of a laminated glass panel with two sets of embedded point connections under a vertical load. It also allowed comparing the behaviour and resistance of two panels of identical total thickness differing in glass ply compositions.

Experimental Investigation of a Transparent Interface Material for Glass Compression Members

In this experimental research a transparent thermoplastic manufactured by the DOW Corporation and known as Surlyn is investigated for use as an interface material in fabrication of an all-glass pedestrian bridge. The bridge is modular in construction and fabricated from a series of interlocking hollow glass units (HGU) that are geometrically arranged to form a compression dominant structural system. Surlyn is used as a friction-based interface between neighbouring HGUs preventing direct glass-to-glass contact. An experimental program consisting of axial loading of short glass columns (SGC) sandwiched between Surlyn sheets is used to quantify the bearing capacity at which glass fracture occurs at the glass-Surlyn interface location. Applied load cases include 100,000 cycles of cyclic load followed by 12 hours of sustained load followed by monotonic load to cracking, and monotonic loading to cracking with no previous load history. Test results show that Surlyn functions as an effective interface material with glass fracture occurring at bearing stress levels in excess of the column-action capacity of an individual HGU. Furthermore, load cycling and creep loading had no effect on the glass fracture capacity. However, the load history had a nominal effect on Surlyn, increasing stiffness and reducing deformation.