Batch Mode Research Articles

Green synthesis of magnesium oxide nanoparticles using extracts of two brown seaweeds for removal of acid black 1 dye from aqueous environments

Water pollution by synthetic dyes, particularly acid black 1, poses a significant environmental challenge. The present study has addressed this issue by synthesizing novel magnesium oxide (MgO) nanocomposites using extracts from Padina sanctae crucis (Psc) and Sargassum hystrix (Sh) algae via a sol-gel process. The primary objective was to evaluate the efficacy of these nanocomposites in removing acid black 1 dye from aqueous solutions. The synthesized materials were characterized using Fourier transform infrared spectroscopy (FT-IR), energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) analysis, thermal gravimetric analysis (TGA), and dynamic light scattering (DLS). The results show the successful synthesis of MgONPs and MgO@Sh and MgO@Psc NPs with approximate sizes of 45.64–65.64, 52.14–59.09 and 39.19–58.30 nm. Batch mode experiments were conducted to assess the influence of contact time, pH, and adsorbent dosage on dye removal efficiency. The results demonstrated that at pH 6, increasing the adsorbent dosage from 0.5 to 2 g/L enhanced the dye removal efficiency from 41.6% to 59.1% for MgO@Psc and from 43.4% to 64.1% for MgO@Sh. The Sips isotherm model and intra-particle diffusion kinetic model provided the best fit to the experimental data. The negative values of ΔG° indicated, which the adsorption process is more spontaneous at higher temperatures. This study highlights the potential of MgO@Psc and MgO@Sh nanocomposites as effective adsorbents for acid black 1 removal, offering a promising solution for water purification.

Kinetic-free sizing criterion for the thermally controlled scale-up of batch fine-chemical processes

A number of newly developed exothermic reactions of the fine-chemical industry can be safely tested at the industrial scale in an existing batch reactor since they cannot lead to dangerous reactor overpressures even under adiabatic conditions. However, when the process is scaled from a laboratory to an industrial reactor, the normal decrease of the heat transfer efficiency per unit volume can be so relevant that at the industrial scale the process cannot be thermally controlled, leading to a lower and less reproducible quality of the final product. In these cases, the industrial reactor must be equipped with an external heat transfer surface in addition to that provided by the reactor jacket only. The sizing of such an additional surface through conventional tools requires the knowledge of the heat release rate in the recommended temperature range and hence of the system kinetic behavior, which is often a missing information in the fine-chemical industry due to the fragmentation of the involved processes. In this work, a kinetic-free sizing criterion is presented for the temperature-controlled scale-up of intrinsically safe exothermic reactions carried out in the batch mode of operation, allowing for a simple and general estimation of the required heat transfer surface at the industrial scale from the analysis of the pseudo-adiabatic temperature trends measured during the original industrial batches. The proposed methodology has been validated using a set of process information about the final nitration step for the synthesis of an API as well as industrial-scale data collected during the scale-up of a water-in-oil emulsion polymerization for the synthesis of a polycationic thickener used in the cosmetic industry.

Characterization of <i>Adansonia Digitata</i> Seed Cake with a View to Identifying an Energy Recovery Strategy

Agri-food processing emits huge quantities of waste and is considered one of today's major environmental problems. There are many different options (anaerobic digestion, thermochemistry and feed production) that can be applied to the management and evaluation of waste treatment. The aim of the present study was to explore the appropriate recovery option for Adansonia digitata seed cake through its characterization. The physicochemical characteristics of <i>Adansonia digitata</i> seed cakes were determined in accordance with international standards. Anaerobic digestion was tested under thermophilic conditions in batch mode over 75 days. Results showed that dry matter content averaged 87.35 ± 0.03%, organic matter content averaged 95.03 ± 0.41%, carbon to nitrogen ratio averaged 19.75. Digestion of <i>Adansonia digitata</i> seed cakes proved highly productive, with a maximum percentage of 68.5% CH<sub>4</sub> for 185.57 liters of biogas, i.e. an average production of 2.47 liters per day for 1720 g DM. The methanogenic potential (BMP) of <i>Adansonia digitata</i> seed cake was 331.21 ml/g of organic matter introduced. <i>Adansonia digitata</i> oilcake had an average gross calorific value of 18.54MJ/Kg. These results are encouraging and mark the start of any study on the energy recovery of <i>Adansonia digitata</i> seed cake in biogas.

Biodecolorization of Azo Dye by Bacteria Alcaligenes faecalis Sub Sp. Phenolicus Isolated from a Bark-Beetle Tunnel Developed in Peltophorum Pterocarpum Plant

This study assessed the decolorization of reactive red 120 (RR120) by Alcaligenes faecalis subsp. phenolicus strain isolated from the bark borer insect (Indarbela tetraonis) tunnel developed in Peltophorum pterocarpum. The optimal parameters for the dye of decolorization 0.1 mg/L of dye were pH 7, temperature 35°C, fructose (0.4% w/v) as the carbon supply (0.4% w/v), peptone (0.2% w/v) as the nitrogen source (0.4% w/v), 12 hours of static conditions, and 0.3 ml of inoculums. Cell suspension, sodium alginate (3%, w/v), and PVA (5%, w/v) immobilized cell beads (10 beads 0.5 mm in size) were used in the batch continuous reactor for complete bio-decolorization of RR120. The batch reactor was subjected to 5 cycles of batches for 3 days of constant use. Under optimal conditions, the batch mode achieved more than 99% dye decolorization and fabric color removal in less than 48 hours of contact. When the control and dye-decolorized media were analyzed using UV spectroscopy, the absorbance of the control medium was higher than that of the decolorized media. GC-MS and FTIR analysis revealed the basic compounds and functional groups of the parent RR120 dye. This strain decolored 76.51% of AB 113, 96.8% of orange II, 98.47% of congo red, 98.3% of RR120, 97.92% of phenol red individual dyes, and 94.72% of the dye mixture at 12 hours. A. faecalis subsp. Phenolicus strains produced positive results in the qualitative analytical test of exopolysaccharides (EPS) and plant growth-promoting rhizobacteria (PGPR) production. The RR120 was decolorized in the presence of heavy metal ions by A. faecalis sub-sp. Phenolicus bacteria.

Development and integration of a continuous horizontal belt filter into drug production procedure

In the pharmaceutical industry, filtration is traditionally carried out in batch mode. However, with the spread of continuous technologies, there is an increasing demand for robust continuous filtration strategies suitable for processing suspensions produced in continuous crystallizers. Accordingly, this study aimed to investigate a lab-scale horizontal conveyor belt filtration approach for pharmaceutical separation purposes for the first time. The newly developed continuous horizontal belt filter (CHBF) was tested under different systems (microcrystalline cellulose (MCC)/water, lactose/ethanol and acetylsalicylic acid (ASA)/water) and diverse conditions. Filtration was robust using a well-defined unimodal particle size distribution MCC in water system, where the residual moisture content varied within narrow limits of 45–52% independently from the process conditions. Besides, the residual moisture content highly depended on the applied solvent and particle size. It could be reduced to below 2% by processing the suspensions of either a volatile solvent (lactose in ethanol) or an aqueous slurry of a large particle size ASA. Finally, the CHBF was connected to a mixed suspension mixed product removal (MSMPR) or a plug flow crystallizer (PFC). The residual moisture content of the CHBF-filtered ASA product and operation characteristics (onset of steady-state) were evaluated in both continuous crystallizer-filter systems. The MSMPR-CHBF system operated with a longer startup period. The size of the in situ-produced crystals was of a similar order magnitude in both systems, resulting in a similar residual moisture content (around 20%). Overall, the tested continuous filter was robust, did not modify the crystal morphology in the examined experimental range, and could be effectively integrated with continuous crystallizers.

Membrane compaction in batch reverse osmosis operation and its impact on specific energy consumption

Reverse osmosis (RO) membrane water permeability is measured under cyclic pressure loading conditions corresponding to batch and semi-batch operation modes. Due to the viscoelasticity of the membrane support layer, compaction effects carry forward across multiple pressurization cycles, with the intracycle behavior stabilizing after a large number of cycles. The average membrane permeability of semi-batch RO systems is lower than that of batch RO, since semi-batch RO spends a larger fraction of its cycle time at higher pressures. The instantaneous permeability in batch RO decreases during the cycle as pressure is increased, but at a lower rate than the steady-state permeability variation with applied pressure. Therefore, the batch permeability values are lower at low pressures and higher at high pressures than the corresponding steady-state values. Since more water is recovered in the initial low-pressure stages of a multi-stage RO system, compaction increases the specific energy consumption of batch RO more than that of staged systems. Other loss mechanisms such as channel and minor pressure losses and high-pressure motor+pump efficiency variation with load further result in batch RO becoming energetically inferior to two- or three-stage RO, especially for low-salinity, high recovery applications.

N/NiO-ornated graphitic fiber-engrained micro-carbon beads: Innovative packed bed type capacitive electrodes for microbial fuel cells

Nitrogen-doped nickel oxide-catalyzed carbon nanofiber-decorated micro-activated carbon beads (NiO-N-CNF/ACB) were synthesized through suspension polymerization and employed as capacitive fixed-packed bed electrodes in microbial fuel cell (MFC-) for wastewater treatment and byproduct electricity generation. The capacitive electrode was meticulously designed to manifest enhanced characteristics crucial for MFC applications. The large specific surface area of NiO-N-CNF/ACB offers advantages in terms of catalytic sites and stored charge produced by electrogenic bacteria to form an electrochemical double-layer on the electrode, thereby enhancing power generation. The incorporation of NiO, coupled with graphitic contents, biocompatibility, and the formation of three-dimensional structures, contributes to the excellent performance of the NiO-N-CNF/ACB electrodes. The NiO-N-CNF/ACB electrodes-based MFC operated in batch mode demonstrated an open-circuit potential of 0.8 V, an impressive maximum power density of 2900 mW/m3, and a noteworthy 74 % reduction in chemical oxygen demand. Additionally, the synthesized NiO-N-CNF/ACB exhibited a remarkable specific capacitance 754 F/g and a cumulative total charge of 255 C/g, surpassing the corresponding values for plain NiO-ACB and ACB. This study positions NiO-N-CNF/ACB as a promising capacitive packed bed electrode material, offering enhanced power generation, efficient wastewater treatment, and superior biofilm formation, thereby advancing the potential for sustainable and efficient MFC systems.

Application of Marine Mollusk Shells (Meretrix lusoria) as Low-Cost Biosorbent for Removing Cd2+ and Pb2+ Ions from Aqueous Solution: Kinetic and Equilibrium Study

The present work aims to evaluate the applicability of mollusk (Meretrix lusoria) shells as a biosorbent for toxic metal ions (Cd2+ and Pb2+) following the batch mode biosorption procedure. Some well-known analytical methods have been used to characterize the biosorbent such as a scanning electron microscope (SEM), an energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction. The mechanism of metal ion biosorption was examined using various analytical techniques. Therefore, an evaluation of operating factors such as contact time, pH, initial concentration of metal ions, biosorbent dose, and temperature was performed. The results obtained in this investigation indicated that the optimum conditions for the biosorption of Cd+2 and Pb+2 ions are as follows: pH = 6; contact times of 90 min; and the 20 mg/L of initial [M2+]. And a biosorbent dosage of 1.0 g/100 mL for each metal ion solution was also determined. The maximum removal efficiency results were 90.6% for Cd+2 and 91.5% for Pb+2 at pH 6.0. The biosorption isotherm was investigated using three forms of linear equilibrium (Freundlich, Langmuir, and Temkin models). Kinetic studies were also conducted to determine the equilibrium time for the biosorption of the studied metals utilizing the pseudo-second-order, pseudo-first-order, and intraparticle diffusion model. The data indicate that the biosorption kinetics of Cd2+ and Pb2+ follow the pseudo-second-order models. According to the present study, it can be identified that the shell of Meretrix lusoria is a suitable biosorbent for Cd2+ and Pb2+ ions and can contribute to their removal from environmentally polluted water.

Bentonite clay reinforced alginate grafted composite hydrogel with remarkable sorptive performance toward removal of methylene green

The rapid industrial progress in today's world has led to an alarming increase in water pollution caused by various contaminants such as synthetic dyes. To address this issue, a new hydrogel sorbent, BC-r-Na-Alg-g-p(NIPAm-co-AAc), was developed by combining bentonite clay, sodium alginate, and poly(N-isopropyl acrylamide-co-acrylic acid) through one-pot free radical polymerization at 60 °C. The developed sorbent was characterized using several analytical techniques including SEM, FTIR, TGA, UTM, and swelling studies. The swelling capacity of the sorbent was observed to increase remarkably with an increase in pH, reaching a maximum of 9664 % at pH 11. In batch mode sorption experiments, the sorbent's performance toward methylene green (MG) was investigated by analysing the effects of contact time, pH, temperature, and concentration. The experimental data were fitted to pseudo-second-order kinetic and Langmuir isotherm models, indicating chemisorption as the dominant interaction mode between the anionic sorbent and cationic MG. However, physisorption may also occur to a lesser extent, indicated by the significant R2 of the pseudo-first-order kinetic and Freundlich isotherm models. Additionally, the sorbent exhibited very little decrease (approximately 5 %) in sorptive performance for six sorption-desorption cycles. Overall, the facile fabrication, excellent swelling (9664 %), promising sorption performance (2573 mg.g−1), and good recyclability (6 cycles) make the developed sorbent a potential candidate for various industrial applications.

Quality by design for mRNA platform purification based on continuous oligo-dT chromatography

Oligo-deoxythymidine (Oligo-dT) ligand-based affinity chromatography is a robust method for purifying mRNA drug substances within the manufacturing process of mRNA-based products, including vaccines and therapeutics. However, the conventional batch mode of operation for oligo-dT chromatography has certain drawbacks that reduce this process’s productivity. Here, we report a new continuous oligo-dT chromatography process for the purification of in vitro transcribed mRNA, which reduces losses, improves the efficiency of oligo-dT resin use, and intensifies the chromatography process. Furthermore, the quality by design (QbD) framework was used to establish a design space for the newly developed method. The optimisation of process parameters, including salt type, salt concentration, load flow rate and mRNA load concentration both in batch and the continuous mode, achieved >90% yield (mRNA recovery) along with >95% mRNA integrity and >99% purity. The productivity of continuous chromatography was estimated to be 5.75-fold higher, and the operating cost was estimated 15% lower, when compared to batch chromatography. Furthermore, the QbD framework was further used to map the relationship between critical quality attributes (CQAs) and key performance indicators (KPIs) as a function of critical process parameters (CPPs) and critical material attributes (CMAs).

Environmental Sustainability of the Removal of Alpaca Fiber Dye Using a Thermally Modified Sludge from a Drinking Water Treatment Facility

In this work, the removal of dye using thermally modified sludge from a drinking water treatment facility (DWTS) was evaluated. This study gives value to the waste from the coagulation flocculation process (waste sludge) in order to remove an emerging organic agent (Bordeaux B). The sustainability of the process leads to a circular economy, which represents an important environmental contribution. The physicochemical characterization of the DWTS was carried out by standard methods. DRX and FTIR spectroscopy, SEM, and superficial specific area SBET N2 at 77 K were used. Thermal activation processes were carried out (200–600 °C) to obtain the best activated thermal conditions for dye removal (T: 500 °C). Muscovite and other minerals were found in the DWTS. Experimental conditions (batch mode) were determined: contact time (CT), pH, adsorbent dose (AD), and dye initial concentration (Co). SBET = 54.77 and 67.90 m2/g by DWTS and TA-500. The best removal efficiency was achieved at 500 °C (R = 85.57 ± 0.76 %, q max = 37.45 ± 0.14 mg/g), which, compared to other unconventional adsorbents, is more reliable and competitive. The adsorption process was adjusted to the Langmuir mathematics model, following pseudo-second-order kinetics (R2 = 0.99).

Electrochemical flow-through disinfection of Escherichia coli versus Staphylococcus aureus: Identifying impacts of flow patterns on efficiency

While Ti4O7 reactive electrochemical membrane (REM) treatment exhibits high efficiency in inactivating bacteria, it remains obscure about the disinfection and antifouling mechanism. Herein, we highlighted the decisive impact of flow patterns on the electrochemical inactivation of both Escherichia coli and Staphylococcus aureus during dead-end filtration mode. Specifically, 5.22 and 5.47 log removal for E. coli and S. aureus were achieved by a single pass under anode-to-cathode (AC) flow pattern at 7 mA cm−2 respectively, while the inactivation rates immediately decreased to less than one log for cathode-to-anode (CA) flow pattern. Further analysis demonstrated that the remarkable inactivation efficiency in neutral condition, the complete inactivation of E. coli and S. aureus in the parallel plate batch mode were achieved in 15 min and 30 min at 7 mA cm−2 respectively, was significantly inhibited during alkaline and acidic exposure, thereby which explained the slow disinfection rates in CA flow pattern due to the formed alkaline experiment near anodic reaction section. The disinfection efficiency and comparative differences of E. coli and S. aureus were also affected by their hydraulic condition and cell wall structure. Functional groups model substances experiments and molecular dynamics simulation elucidated that the response changes of cell structure especially denser membrane protein complex under alkaline and acidic exposure resisted electrooxidation attack to the membrane structure. These findings here provide insights into the application of Ti4O7 REM technologies in controlling waterborne disease transmission.

Solving crystallization/precipitation population balance models in CADET, Part II: Size-based Smoluchowski coagulation and fragmentation equations in batch and continuous modes

A particle size-based Smoluchowski coagulation and fragmentation equation was solved in the free and open source process modeling package CADET. The WFV and MCNP schemes were selected to discretize the internal particle size coordinate. Weights in these schemes were modified to preserve and conserve the zeroth and third moments for size-based equations. Modified propositions and proofs for the scheme are provided. Analytical Jacobians were derived and implemented to reduce the solver’s runtime. A two-dimensional Smoluchowski coagulation and fragmentation equation with axial position as external coordinate was formulated and discretized to support simulations of continuous particulate processes in dispersive plug flow reactors. Five 1D and four 2D test cases were used to validate the implementation and benchmark the solver’s performance. The runtime, L1 error norm, L1 error rate, particle size distribution moments up to sixth order and several scalar metrics were analyzed in detail.

Modification of polyethylene for oil-water separation in industrial wastewater treatment

Low-density polyethylene (LDPE) is extensively used worldwide in various applications due to its versatile features and abundant commercial availability. This study investigated, for the first time, the beneficial use of a novel chemically modified commercial-grade LDPE as a sorbent for oil-water separation in industrial wastewater treatment. Several laboratory tests were conducted in batch and continuous fixed-bed modes to evaluate the LDPE adsorbent’s capacity, performance repeatability and recyclability under relevant field conditions. These results were compared to walnut shell (WS), a widely used sorbent for removing oil from industrial wastewaters, including produced water from oil and gas operations. Untreated LDPE achieved higher total organic carbon (TOC) removals and retention capacities, ∼20 % and ∼66 mg/g, respectively, when compared to untreated WS, <5 % and <1 mg/g, respectively. Improved kinetics and adsorption behavior favorability were achieved for LDPE after chemical modification using a cationic monomer. Both the chemically treated LDPE and WS showed comparable TOC removal rates (ranging from 60 % to 80 %). However, the modified LDPE exhibited higher sorption capacities (∼61 mg/g) compared to the treated WS (8.0 mg/g). Chemical regeneration of LDPE with toluene demonstrated superior performance recovery (>90 %) when compared to physical cleaning with deionized water (<40 %). The study presented promising results in advancing novel materials like LDPE to support circular economy in industrial wastewater treatment.

Enhanced biodegradation of lignin and lignocellulose constituents in the pulp and paper industry black liquor using integrated magnetite nanoparticles/bacterial assemblage

The study was designed to explore the efficiency of magnetite nanoparticles (Fe3O4 NPs)/bacterial cell assembly to biodegrade lignin and lignocellulose, decontaminate pulp and paper-contaminated wastewater and optimize lignin adsorption by Fe3O4 NPs. Water samples were collected from three paper and carton manufacturing companies, Alexandria Governorate, Egypt. Pseudomonas otitidis MCC10330, the most active and promising strain among 10 previously screened indigenous and exogenous isolates, was selected and decorated with magnetic Fe3O4 Nanoparticles, that were prepared by the co-precipitation method, characterized and used to decontaminate paper and pulp effluent in a batch mode bioassay for 4 h. Fe3O4 NPs/bacterial cell assembly achieved the highest removals (64.1, 52.0, 54.3 and 66.6%) of TSS, COD, BOD, and Total Tannin and Lignin after 1, 4 and 4 h, reaching residual concentrations (RCs) of 322, 216, 112 and 7 mg/L, which are still slightly higher (5.35, 2.7 and 1.86-fold) than their maximum permissible limits (MPLs), respectively. RCs of pH, DO and TDS in the treated effluent are accepted for safe discharging. Maximum lignin adsorption and removal (82.14%) using Fe3O4 NPs was achieved at the optimized conditions (pH 6, Fe3O4 NPs dosage of 100 mg and 10 min contact time). Results confirmed that the proposed magnetite-coated Pseudomonas otitidis treatment system is highly efficient and recommended to treat the highly contaminated pulp and paper wastewater. Also, as far as we know, this integrated assemblage is the first time to be used as a novel, very promising, eco-friendly, renewable and economical biotechnological approach to minimize/eliminate the involved pollutants with the least running time.

Effect of microwave and ultrasonic pre-treatments on anaerobic co-digestion of orange wastes and municipal sewage sludge: A case study

The application of orange wastes (OW) in anaerobic digestion process still constitutes a technological challenge. One of the possibilities to overcome this issue is application of pre-treatment strategy. In this study, the effect of microwave (MW) and ultrasonic (US) pre-treatments on OW and sewage sludge (SS) co-digestion was examined. Firstly, the selection of optimal pre-treatment conditions in terms of solubilisation and generation of inhibitors (phenol and limonene contents) was conducted. For MW, irradiation time of 10 min and specific energy input of 28 089 kJ/kgTS were chosen as optimal. For US pre-treatment, specific energy input of 8914 kJ/kgTS and time of 20 min were adopted. Then, the mesophilic anaerobic co-digestion in batch mode was performed. However, neither of the two proposed pre-treatments had a significant impact on methane production, as compared to the untreated sample.

Catalytic gasification as a management strategy for wastes from pecan harvest

More than 60,000 tons of waste from Carya illinoinensis, known as pecan, are produced yearly in Mexico. Usually, these wastes are either open-cast disposed of or burned, causing environmental issues. An alternative to combustion is gasification, which transforms biomass into syngas and ash. Using a catalyst can improve the gasification reaction since it allows for better heat transfer in the reactor. In this work, a gasification process catalyzed by a clinoptilolite was evaluated as a method of pecan waste management. A fixed bed gasifier in batch mode with a reaction volume of 1 kg was considered. Gasification with 8 % zeolite presented the shortest reaction time (39 min) and the highest average flow of synthesis gas (0.779 m3/5 min). The environmental impact was evaluated through a life cycle assessment considering two scenarios: conventional and catalyzed gasification (2, 4, 6, and 8 % of zeolite). In the former, the gasification stage induces the largest potential impact (>95 %) in all the categories, and global warming is the most affected category (>90 %). In the second scenario, gasification (82 %) and zeolite production (16 %) stages are the main potential impact inducers; global warming is also the most affected category (85 %). Considering the experimentation and environmental assessment, gasification with 8 % zeolite was selected for the next stage. Regarding economic feasibility, it was found that a pilot-scale gasification processing 1000 kg of pecan waste becomes feasible if gas is either sold or used to produce electricity.

Crystallization of Bis(2-hydroxyethylene) Terephthalate as a Part of a Bottle-to-Bottle Recycling Concept for Poly(ethylene terephthalate).

The chemical recycling of poly(ethylene terephthalate) (PET) is very attractive as PET bottle waste provides an abundant clean material with low levels of additives. One of the most promising processes is glycolysis, which depolymerizes PET in the presence of ethylene glycol. For this process, it is necessary to think through the whole concept, from the waste material to the newly polymerized virgin polymer. Most research ends with determining the yield of bis(2-hydroxyethyl)terephthalate (BHET) after glycolysis. Some research includes antisolvent crystallization with water to separate BHET from ethylene glycol. However, the subsequent separation of water and ethylene glycol is an energy-intensive process. Therefore, this work aims to directly crystallize BHET from ethylene glycol. For this reason, the crystallization of BHET was investigated experimentally. Crystallization was simulated using gPROMS Formulated Products with the aim of estimating kinetic parameters and using these to optimize an industrial process. Kinetic parameters were determined by model validation, including primary and secondary nucleation and crystal growth. The best-fitting set of kinetic parameters was used to optimize BHET crystallization in batch and continuous modes by minimizing equipment costs. Impeller parameters were found to have a great influence on crystallization performance. Ultimately, the continuous and batch processes gave comparable results in terms of equipment cost, with the batch process giving larger crystals and higher yields but the continuous process requiring a smaller crystallizer.

Constructing a monolithic amino-functionalized poly(ether sulfone) loose nanofiltration membrane for efficient dye/salt fractionation

Loose nanofiltration (LNF) is a promising new technique for dye/salt separation, but LNF membranes still suffer from low permeance and inadequate selectivity. In this study, novel monolithic amino-functionalized poly(ether sulfone) (PES) LNF membranes were developed in three steps, PES powder-grafted with polyacrylonitrile (PAN) under gamma-ray irradiation and membrane preparation via non-solvent-induced phase separation, followed by an amination process. The resultant aminated PES LNF membrane with tetraethylenepentamine (APES-TP) had a thinner skin layer and unusual irregular vesicle-like pore structure in its sublayer compared with the original PES substrate. The amination process increased the hydrophilicity of the APES-TP membranes and partially neutralized the surface zeta-potential. The permeation test confirmed that the APES-TP membrane exhibited 100 % NaCl permeation together with high levels of pure water permeance (77.9 L m–2h−1 bar−1) and dye rejection (98.5 % for Congo red, 97.1 % for Nair blue, and 97.6 % for methyl blue). Even when paired with simulated industrial wastewater containing multiple direct dyes and inorganic salts (1 g L–1 dye and 5 g L–1 salts), the APES-TP membrane still rejected 99.4 % of the mixed dyes, proving its practical applicability to treating industrial dye wastewater. Furthermore, the APES-TP membrane exhibited excellent endurance to harsh conditions (such as acidic, alkaline, and oxidative) and exceptional recyclability (97.9 % permeance recovery rate). This study bridges the gap between conventional nonsolvent phase inversion and the emerging LNF membrane fabrication technology, allowing the LNF technique to be used to fractionate organic matters with salts in batch mode.

Enhanced query performance for stored streaming data through structured streaming within spark SQL

Traditional database systems like relational databases can store data which are structured with predefined schema, but in the case of bigdata, the data comes in different formats or are collected from diverse sources. The distributed databases like not only spark querying language (NoSQL) repositories are often used in relation to bigdata analytics, but a continual updating is required in business because of the streaming data that comes from stock trading, online activities of website visitors, and from the mobile applications in real time. It will not have to delay, for some report to show up, to assess and analyse the current situation, to move forward with the next business choice. Apache Spark’s structured streaming offer capabilities for handling streaming data in a batch processing mode with faster responses compared to MongoDB which is a document-based NoSQL database. This study completes similar queries to evaluate Spark SQL and NoSQL database performance, focusing on the upsides of Spark SQL over NoSQL databases in streaming data exploration. The queries are completed with streaming data stored in a batch mode.