Water Absorption Enhancement of Sodium Poly Acrylate and Poly(2-Acrylamido-2-Methylpropane Sulphonic Acid) Based Hydrogel Mixtures

Introduction: Hydrogels are hydrophilic polymers which are cross-linked to form three-dimensional structures, which can absorb, swell and retain huge amounts of water or aqueous fluids. Objective: This paper reports the preparation and characterisation of Poly(2-Acrylamido-2-Methylpropane Sulphonic Acid) (PAMPS) hydrogel with different crosslinking intensities. Methodology: 2-Acrylamido-2-methylpropane sulfonic acid (AMPS) monomer was purchased from Alfa Aesar Company as reagent grade. It was used as received (>98% purity) without any further purification. PAMPS hydrogel was prepared by free radical crosslinking solution polymerization of AMPS in water at room temperature under a nitrogen blanket in cylindrical glass tubes. The characteristics of the obtained PAMPS hydrogel were compared with those of commercial sodium polyacrylates hydrogel. Results: It was found that decreasing the crosslinker weight improved the absorbance capacity but to a limit. The suggested reasons were discussed. The mixture showed higher absorbance rate than PAMPS, and bigger absorbance capacity than sodium polyacrylates. Conclusion: This paper investigates the effect of crosslinker ratio on the swelling capacity of PAMPS. It was found that as the crosslinking ratio decreases, the porosity of the hydrogel increases, thus improving the swelling capacity.

Neutralizing Aminesin Boiler Steam and Humidified Indoor Air

Objective: The health and comfort of the indoor population have been impacted by the humidity. While people are increasingly spending more time indoors, the presence of pollutants and lack of proper humidification in indoor air have significant risk factors that may lead to multiple health problems. Methods: By applying the right air purification and/or humidification system, the adverse effects of poor indoor air quality can be minimized. Direct steam addition is a common technique to humidify the indoor air of a building. Carbon dioxide or other acidic process contaminants may dissolve in steam or steam condensate that will consequently decrease the pH and make it corrosive for the steam distribution system. To avoid that, neutralizing amines are added to steam that keeps the pH neutral or slightly alkaline(pH 7.5-9.0). However, neutralizing amines have some toxic effects. OSHA, FDA, and NIOSH prescribe maximum concentration limits for them in indoor air. The Central Utility Plant (CUP) of National Institutes of Health (NIH) uses a 50:50 blend of cyclohexylamine and diethylaminoethanol as neutralizing agents for the steam. Results: The CUP at NIH presents the results of monitoring the concentration level of amines through mass balance, online monitoring at specified location of the steam distribution system and field measurement in humidified indoor air at buildings on campus. Conclusion Through theoretical calculation backed up by field measurement, the amine concentration of indoor air is determined to be well below the FDA regulated limits.

Fast and Facile Voltammetric Detection of Acetaminophen at Poly (DL-phenylalanine) Modified Dysprosium-Copper Oxide Nanoparticle/Carbon Composite Paste Electrode

Introduction: The voltammetric sensing of Acetaminophen (AN) using modified Dysprosium Copper Oxide (DyCuO) Nanoparticles (NP) mixed Carbon Paste Electrode (MCPE) was successfully developed. Methods: The modification of bare NPMCPE was achieved by the polymerisation of DL-Phenylalanine (DLPA). The electroanalysis of the AN was achieved by utilizing the Cyclic voltammetry (CV) approaches. The crystallographic nature of the nanoparticle was studied via X-ray Powder Diffraction (XRD) technique. The surface morphology and electrochemical feature of the prepared electrode were evaluated by Field Emission Scanning Electron Microscopy (FE-SEM) and Electrochemical Impedance Spectroscopy (EIS) techniques. Results: The modified sensor exhibited an excellent electrocatalytic activity towards the electroanalysis of the AN. Several aspects, such as the number of polymerisation cycles, variation of pH, and the impact of scan rate were investigated in 0.2 M supporting electrolyte (pH 7) at a sweep rate of 0.1 Vs-1. The suggested sensor shows a very low detection limit (11.95×10-8 M) with a linear range of 2.0 to 50.0 µM, which exhibits excellent sensitivity. Conclusion: The stable and reusable sensor was applied for the estimation of AN in the tablet sample. Thus, P(DLPA)MNPMCPE was utilized as the most capable sensor for the voltammetric detection of AN.

Application Of Seeding Crystallization as a Pre-Treatment Stage for The Reduction of Scaling Tendency of Seawater Feed to Thermal Desalination Units

Objective: The fouling inhibition in seawater desalination and scale control using crystallization with calcite seeds is evaluated experimentally in this study. Methods: The growth kinetic parameters are determined experimentally, correlated and discussed at different operating conditions. Supersaturation levels represent driving force behind the growth of crystals, which is influenced directly by seawater pH values and temperatures. Results: Results indicate that the initial pH value of seawater must be controlled to be in the range (8-9) and calcite seeds will not have the potential to start the growth process in seawater at the normal pH (7.36). The growth kinetic parameters are determined from the measured desupersaturation curves. Conclusion: It is found that the growth process of calcite is controlled by the surface integration step. The growth rate of calcite increases with increasing temperature and seeding ratio (up to 1 g/L), while it decreases with increasing the salinity of seawater.

Potential Evaluation of PVDF/PAN Membranes for Separation of Oil from Industrial Waste

Aim: The aim of the experiment is to characterize the Modified Membrane from PVDF/PAN and its application in removing the Emulsified oil waste from the Industry. Objective: To get the maximum separation of the emulsified oil from the waste water, composite (PVDF/PAN) membrane was prepared in the laboratory. Methods: New PVDF/PAN blend based ultrafiltration membranes were synthesized by phase inversion method. The blend membrane was treated at room temperature with aqueous sodium hydroxide solutions. Results: The facile eco-friendly preparation of PVDF/PAN blended membrane has a wide potential for practical applications in emulsified wastewater remediation. The chemical functionality of the modified membranes was confirmed by IR spectra. Conclusion: For the separation of emulsified oily wastewater, the as-prepared composite (PVDF/PAN) membrane could effectively separate oil/ water emulsions with separation efficiency of above 99.8%. Unmodified membranes (A and B) showed 95.4-99.8% rejection. However, in the case of membranes C and D, oil rejection was higher for the modified membranes as compared to the unmodified membranes.

Better Heat and Power Integration of an Existing Gas-Oil Plant in Egypt Through Revamping the Design and Organic Rankine Cycle

Objective: The current study aims mainly to Maximize Condensate Recovery (NGLs), focusing on a gas processing train of Gas-Oil Separation Plant (GOSP) located in Egypt with a capacity of 4,230 kmole/h. Methods: The research study accounts for the constraint of Reid Vapor Pressure (RVP) specification, which makes the storage in floating roof tanks is of a great risk. The study proposes the installation of the cryogenic train that recovers condensates (C4+). This train comprises of compression unit, expansion unit, three-phase separators and a re-boiled absorber. The problem of RVP will no longer exist because of the re-boiled absorber achieving RVP according to export specifications (RVP below 82.74 kPa). Heat integration is applied over the whole process to minimize the reliability of the external utilities. Further, an Organic Rankine cycle (ORC) is introduced to the existing unit for more heat integration to develop useful work from process waste heat. Furthermore, both environmental emissions of CO2 and economic implications are investigated. Results: Energy integration played a vital role in decreasing the compressing power by about 31%, the cooling load by about 81%, and eliminating the heating load leading to zero CO2 emissions. Conclusion: The new energy-integrated retrofit scenarios exceed the recommended revamping schemes by previous works and base case in all aspects of condensate recovery, energy-saving, environmental concerning and economics.

Electrochemical Fabrication of Poly (niacin) Modified Graphite Paste Electrode and its Application for the Detection of Riboflavin

Objective: A poly niacin (NN) modified graphite paste electrode was prepared through a simple electrochemical polymerization route for the determination of Riboflavin (RF) Methods: Electropolymerization technique was used for the preparation of a modified electrode. The electrochemical impedance spectroscopy (EIS) method was used to study the surface behaviors and conductivity of the bare and modified electrodes. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) were used to study the electrochemical behavior of RF using 0.2 M PBS of 7.5 pH. Results: Poly niacin modified graphite paste electrode (PNNMGPE) provides more affinity towards RF detection with high sensitivity and selectivity over bare graphite paste electrode. RF calibration curve was obtained by LSV between 5.0 µM to 65.0 µM with 0.782 µM limit of detection (LOD) and 2.7608 µM limit of quantification (LOQ), respectively. Selective analysis of RF in the presence of ascorbic acid (AA) and dopamine (DA) was performed at PNNMGPE by the LSV method. Conclusion: The developed PNNMGPE was tested for RF analysis in a multivitamin tablet with good results. Furthermore, the developed electrode shows good stability and reproducibility.

Heat Transfer Modeling in Bone Tumour Hyperthermia Induced by Hydroxyapatite Magnetic Thermo-Seeds

Background: Hyperthermia is an adjuvant oncologic thermal therapy. In the case of deep-seated bone cancers, the interstitial hyperthermia treatment can be performed using thermo-seeds, implanted biomaterial components that are able to convert external electromagnetic power into thermal one. Several magnetic biomaterials have been synthesized for thermal treatments of cancer. However, less attention has been paid to the modeling description of the therapy, especially when the bio-heat transfer process is coupled to the electromagnetic heating. Objective: In this work, a comparison between the available analytical and numerical models is presented. Methods: A non-linear multiphysics model is used to study and describe the performance of cylindrical magnetic hydroxyapatite thermo-seeds to treat residual cancer cells of bone tumours. Results: The thermal dynamics and treatment outcome are carefully evaluated. Under the exposure of a magnetic field of 30 mT, working at 300 kHz, it was found that magnetic hydroxyapatite implants with a size of 10 mm × 10 mm could increase the temperature above 42 °C for 60 min. Conclusion: The proposed model overcomes the limitations of the available theoretical frameworks, and the results reveal the relevancy of the implant geometry to the effectiveness of the hyperthermia treatment.

Drying of Banana-Stepwise Effect in Drying Air Temperature on Drying Kinetics

Objective: Three Different varieties of Banana namely Dwarf Cavendish (Ankleshwar region), Lacatan (Valia region) and Harichal (Bharuch region) were collected from the south Gujarat region, India to check the drying parameters. A pilot scale natural draft tray dryer was used for the drying experimental work. Methods: The performance of all the varieties of banana were verified with and without blanching operation. Change in colour, texture, shrinkage and appearance were studied. Blanching has a remarkable effect on the appearance and shrinkage of the banana samples. Results: On the other side, temperature does not show any countable effect on the shrinkage. For the Lacatan and Harichal banana samples, observed shrinkage was found to be very less at 60 º C and 70 º C while for Dwarf Cavendish sample, shrinkage was found more effective at all varying temperature ranges. Conclusion: Appearance, Colour and Texture of Dwarf Cavendish and Harichal were found to be significant at 70 º C and 80 º C while for Lacatan, no such acceptable changes were observed. Overall, blanching was found to be effective in improving the appearance and colour of all varieties of banana.

Analysis of the Effect of Separate Collection on the Composition of Mixed Municipal Solid Waste in Italy

Separate collection of municipal solid waste (MSW) is mandatory in Italy, and an increasingly higher standard of efficiency is applied; in fact, the target value set by regulation is 65%. In the last 20 years, separate collection efficiency increased from 9.4% with 80% national MSW landfilled, and only one region was over 25% separate collection to 58.1% with 22% national MSW landfilled and 12 of 20 regions over 55% separate collection. However, significant differences are present in the three Italian macro regions (North, Center and South). This paper analyzes the composition of waste carried in most Italian regions to evaluate the effect of separate collection on the composition of mixed municipal solid waste (unsorted). Moreover, a regression analysis on the same data allows to assess this latter as a function of separate collection efficiency.