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Attempts are made to utilize the aqueous extracts of natural compounds, namely cordia latifolia and curcumin, as corrosion inhibitors for mild steel in cooling systems, and their inhibition efficiencies are compared with that of Hydroxyethylidene 1‐1 diphosphonic acid (HEDP). HEDP is also blended with aqueous extracts of natural compounds so as to improve their inhibition efficiency. The blowdown of the cooling system is also analysed for environmental factors.

The purpose of this paper is to cover some aspects about the disposal and regulatory standard around the world toward hospital effluent discharge, its managements and treatment technologies that are adopted and best suitable nowadays.

Due to large and variety of antibiotics available in the market nowadays it is difficult to control its use, thereby risking the whole ecosystem and its components. The regulation pattern is variable depending upon the various factors in different countries. The permissible limit of these emerging pollutants found in sewage as compared to in hospital effluent streams having active pharmaceutical ingredients is very narrow and is a debatable issue.

The disparity in the available legislation for hospital waste management in different countries makes it difficult to compare pro’s and con’s of methods adopted. Strict laws need to be framed for hospital wastewater management and its treatment, as it contains harmful compounds in higher concentrations resulting in development of resistant genes. The guideline applicable nowadays makes it clear that, specific management guidelines with respect to HWW, but also indicate certain characteristics that can be represented to specify their nature and indicator.

Determination of effluent characteristic for each specialized treatment need to be analyzed for meeting the framed regulatory standards. Up-gradation of existing treatment facilities, adopting new technologies and improving operation, maintained is a viable option. As there are no specific treatment schemes available hence combination and optimization of treatment methods may solve the problem to certain extent.

There is some flexibility also there so that law framework can be modified accordingly. For any health facilities direct discharges into natural water bodies it effluent need to follow national discharge standards. These are quite strict as compared to indirect standards and generally not meet by such facilities. This is quite logical because they are not being monitored or treated by municipal systems.

The law indicates that hospital needed to collect and treat effluent according to the treatment standards. But on other hand the law was made making it consideration about the HWW collection in water bodies.

The best way of management as described, is to treat HWW onsite-dividing into primary, secondary and tertiary. The document also provides details about sludge disposal, possible reuse, including the application of new and innovative treatment technologies for HWW. It also provides guidance for minimum approach for HWW management because developing countries patients do not have proper sanitation facilities.

The influence of a newly synthesised organic compound on the inhibition of corrosion of arsenical aluminium brass in a NaCl solution has been investigated using weight loss measurements, potentiodynamic polarization studies and impedance measurements. Different corrosion kinetic parameters obtained from polarisation studies reveal that the inhibition of corrosion of arsenical aluminium brass in NaCl is under mixed control. UV‐reflectance, X‐ray diffraction and scanning electron microscopic studies have also been carried out to understand the mechanism of inhibition of corrosion, and also the morphological changes on the surface of the alloy. The adsorption of this compound on the metal surface from 3.5% NaCl solution is found to obey Temkin’s adsorption isotherm.

This study aims to study electrochemically and by weight-loss experiments the effect of UAE Rhazya Stricta Decne extract on the corrosion inhibition of mild steel in 1.0 M HCl solution, which will serve researchers in the field of corrosion.

Weight loss measurements were carried out on mild steel specimens in 1.0 M HCl and in 1.0 M HCl containing various concentrations (ranging from 2.0 to 0.002 g/L.) of the UAE Rhazya Stricta Decne extract at temperatures ranging from 303 to 343 K.

The aqueous Rhazya Stricta Decne leaves extract was found to be a highly efficient inhibitor for mild steel in 1.0 M HCl solution, reaching about 90 per cent at 2.0 g/L and 303 K, a concentration considered to be very moderate. Even with one-tenth of that concentration, 0.2 g/L, an inhibition of about 82 per cent was obtained at 303 K. The rate of corrosion of the mild steel in 1.0 M HCl is a function of the concentration of the Rhazya Stricta Decne extract. This rate increases as the concentration of the Rhazya Stricta Decne extract is increased. The percentage of inhibition in the presence of this inhibitor was decreased with temperature which indicates that physical adsorption was the predominant inhibition mechanism because the quantity of adsorbed inhibitor decreases with increasing temperature.

This inhibitor could have application in industries, where HCl solutions at elevated temperatures are used to remove scale and salts from steel surfaces, such as acid cleaning of tankage and pipeline, and may render dismantling unnecessary.

This paper is intended to be added to the family of green corrosion inhibitors which are highly efficient and can be used in the area of corrosion prevention and control.

The inhibition effects of sodium silicate and polyphosphate on corrosion of carbon steel in a potable water supply have been studied using weight loss, electrochemical impedance and Tafel polarization measurements. In the water supply under test there were sufficient calcium ions, (220 ppm), to form the normal polyphosphates salts, which is a requisite for good protection. It was concluded that the inhibition efficiency of polyphosphate was higher than that of silicate. The synergistic inhibition effects of polyphosphate on the inhibition of silicate were studied. The results illustrated that silicates and polyphosphates can be useful as corrosion inhibitors for reducing the corrosion of carbon steel in potable water supply distribution systems. The optimal concentration for silicate alone was determined to be 11 ppm and for polyphosphate alone was 8 ppm. The optimum ratio of concentration for sodium silicate to sodium polyphosphate was 4 : 3.

All those effluent streams having compromised characteristics pose negative effects on the environment either directly or indirectly. Health care facilities and hospitals also generate a large amount of effluent like other industries containing harmful and toxic pharmaceutical residual compounds due to uncontrolled use of drugs, besides others. The occurrence of antibiotic in the environment is of utmost concern due to development of resistant genes. These get mixed up with ground and surface water due to lack of proper treatment of hospital wastewater. The effect of pharmaceutical compounds on human society and ecosystem as a whole is quite obvious. There are no strict laws regarding discharge of hospital effluent in many countries. Contrary to this, the authors do not have appropriate treatment facilities and solution to solve day by day increasing complexity of this problem. Moreover, water discharged from different health facilities having variable concentration often gets mixed with municipal sewage, thus remains partially untreated even after passing from conventional treatment plants. The purpose of this paper is to highlight the occurrences and fate of such harmful compounds, need of proper effluent management system as well as conventionally adopted treatment technologies nowadays all around the globe. This mini-review would introduce the subject, the need of the study, the motivation for the study, aim, objectives of the research and methodology to be adopted for such a study.

Hospital effluents consisting of pathogens, fecal coliforms, Escherichia coli, etc, including phenols, detergents, toxic elements like cyanide and heavy metals such as copper (Cu), iron (Fe), gadolinium (Gd), nickel (Ni), platinum (Pt), among others are commonly detected nowadays. These unwanted compounds along with emerging pollutants are generally not being regulated before getting discharged caused and spread of diseases. Various chemical and biological characteristics of hospital effluents are assessed keeping in the view the threat posed to ecosystem. Several research studies have been done and few are ongoing to explore the different characteristics and compositions of these effluent streams in comparison so as to suggest the suitable conventional treatment techniques and ways to manage the problem. Several antibiotic groups such as ciprofloxacin, ofloxacin, sulfa pyridine, trimethoprim, metronidazole and their metabolites are reported in higher concentration in hospital effluent. The aquatic system also receives a high concentration of pharmaceutical residues more than 14,000 μg/L from treatment plants also and other surface water or even drinking water in Indian cities. Many rivers in southern parts of India receives treated water have detected high concentration drugs and its metabolites. As far as global constraints that need to be discussed, there are only selected pharmaceuticals compounds generally analyzed, issue regarding management and detection based on method of sampling, frequency of analysis and observation, spatial as well as temporal concentration of these concerned micropollutants, accuracy in detecting these compounds, reliability of results and predictions, prioritization and the method of treatment in use for such type of wastewater stream. The complexity of management and treatment as well need to be addressed with following issues at priority: composition and characterization of effluent, compatible and efficient treatment technology that needs to be adopted and the environment risk posed by them. The problem of drugs and its residues was not seen to be reported in latter part of 20th century, but it might be reported locally in some part of globe. This paper covers some aspect about the disposal and regulatory standard around the world toward hospital effluent discharge, its managements and treatment technologies that are adopted and best suitable nowadays various industries and monitoring the efficiencies of existing treatment systems. This mini-review would introduce the subject, the need, the motivation and objectives of the study and methodology can be adopted for such a study.

The compiled review gives a complete view about the types of antibiotics used in different health care facilities, their residue formation, occurrences in different ecosystems, types of regulations or laws available in different counties related to disposal, different type of treatment technologies, innovative combined treatment schemes and future action needed to tackle such type of effluent after its generation. The thesis also highlights the use of certain innovative materials use for the treatment like nanoparticles. It also discusses about the residues impact on the human health as well as their bioaccumulative nature. If the authors relate the past to the current scenario of pharmaceutical compounds (PhACs) in the environment, the authors will certainly notice that many diseases are nowadays not curable by simple previously prescribed Ab. Many research projects have been done in European countries that have shown the risk of such residues like Pills, Sibell, Poseidon, No pills, Neptune, Knappe, Endetech, etc. In the previous section, it was mentioned that there are no stringent laws for hospital wastewater and in many countries, they are mixed with domestic wastewater. Many difficulties are there with this research due to complex analysis, detection of targeted Ab, affecting waterbodies rate of flow, nature of treatment varies with season to season. The way nature is being degraded and harmful effect are being imposed, it is important to take immediate and decisive steps in this area. Wastewater treatment plants (WWTPs) serves as a nursery for antibiotic-resistant systems, hence monitoring with great attention is also needed. Many trials with different treatment process, in combination, were considered. Many countries are paying great attention to this topic by considering the severity of the risk involved in it.

Previous studies by several scientists show that the pharmaceutical residues in the discharged effluent displayed direct toxic effects, and sometimes, detrimental effects in the mixture were also observed. The discharge of untreated effluent from hospitals and pharmaceuticals and personal care products in the natural ecosystem poses a significant threat to human beings. The pharmaceuticals, like antibiotics, in the aquatic environment, accelerate the development of the antibiotic-resistant genes in bacteria, which causes fatal health risks to animals and human beings. Others, like analgesics, are known to affect development in fishes. They also degrade the water quality and may lead to DNA damage, toxicity in lower organisms like daphnia and have the potential to bioaccumulate. A few commonly used nanoadsorbents for water and wastewater treatment along with their specific properties can also be used. The main advantages of them are high adsorption capacity and superior efficiency, their high reusability, synthesis at room temperatures, super magnetism, quantum confinement effect as well as eco-toxicity. This review will focus on the applicability of different nanoscale materials and their uses in treating wastewater polluted by organic and inorganic compounds, heavy metals, bacteria and viruses. Moreover, the use of various nanoadsorbents and nano-based filtration membranes is also examined.

A number of different pharmaceutical residues derived from various activities like production facilities, domestic use and hospitals have been reported earlier to be present in groundwater, effluents and rivers, they include antibiotics, psycho-actives, analgesics, illicit drugs, antihistamine, etc. In past few years environmental scientists are more concerned toward the effluents generated from medical care facilities, community health centers and hospitals. Various chemical and biological characteristics of hospital effluents have been assessed keeping in the view the common threats pose by them to the entire ecosystem. In this study, seven multispecialty hospitals with nonidentical pretreatment were selected for three aspects i.e. conventional wastewater characteristics, high priority pharmaceuticals and microbial analyses. The present work is to evaluate efficacy of advanced wastewater treatment methods with regard to removal of these three aspects from hospital effluents before discharge into a sewage treatment plant (STP). Based on test results, two out of seven treatment technologies, i.e. MBR and CW effectively reducing conventional parameters and pharmaceuticals from secondary and tertiary treatments except regeneration of microbes were observed in tertiary level by these two treatments.

This review has aimed to identify the emerging contaminants, including pharmaceutical residues, highly consumed chemicals that are present in the hospital effluent, along with their physicochemical and biological characteristics. In this, the main objective was to review the occurrences and fate of common drugs and antibiotics present in effluents from hospital wastewaters. As far as global constraints that need to be discussed, there are only selected pharmaceuticals compounds generally analyzed, issue regarding management and detection based on method of sampling, frequency of analysis and observation, spatial as well as temporal concentration of these concerned micropollutants, accuracy in detecting these compounds, reliability of results and predictions, prioritization and the method of treatment in use for such type of wastewater stream are among the major issues (Akter et al., 2012; Ashfaq et al., 2016; García-Mateos et al., 2015; Liu et al., 2014; Mubedi et al., 2013; Prabhasankar et al., 2016; Sun et al., 2016; Suriyanon et al., 2015; Wang et al., 2016; Wen et al., 2004). This paper covers some aspect about the disposal and regulatory standard around the world toward hospital effluent discharge, its managements and treatment technologies that are adopted and best suitable nowadays.

This study many multispecialty hospitals with nonidentical pretreatment were selected for three aspects i.e. conventional wastewater characteristics high priority pharmaceuticals and microbial analyses. The present work is to evaluate efficacy of advanced wastewater treatment methods with regard to removal of these three aspects from hospital effluents before discharge into an STP. Based on test results, two out of different treatment effectively reducing conventional parameters and pharmaceuticals from secondary and tertiary treatments except regeneration of microbes were observed in the tertiary level by these two treatments were studies followed by ozonation and ultraviolet-ray treatment.

The widespread use of washing machines in textile dyeing and finishing boosts product quality while leading to significant wastewater production. This wastewater poses environmental risks due to the textile industry's high pollution levels and water consumption. Sustainability hinges on minimizing water usage and treating wastewater for reuse. This study employs Matlab R2020a and Python 2023 to model experimental designs for treating textile production wastewater using the Fenton oxidation method, aiming to address sustainability concerns in the industry.

The Fenton oxidation process's efficacy and optimal operating conditions were determined through experimental sets employing the Box–Behnken design. Assessing machine learning algorithms on the data, Matlab R2020a utilized an artificial neural network (ANN), while Python 2023 employed support vector regression (SVR), decision trees (DT), and random forest (RF) models. Evaluation of model performance relied on regression coefficient (R2) and mean square error (MSE) outcomes. This methodology aimed to refine the Fenton oxidation process and identify the most efficient parameters, leveraging a combination of experimental design and advanced computational techniques across different programming platforms.

The study identified optimal conditions: pH 3, Fe+2 concentration of 0.75 g/L, and H2O2 concentration of 5 mM, yielding 87% COD removal. The Box–Behnken design achieved a high R2 of 0.9372, indicating precise predictions. Artificial neural networks (ANN) and support vector regression (SVR) exhibited successful applications, notably achieving an R2 of 0.99936 and low MSE of 0.00416 in the ANN (LOGSIG) model. However, decision trees (DT) and random forests (RF) proved less effective with limited datasets. The findings underscore technology integration in treatment modeling and the environmental imperative of wastewater purification and reuse.

This study, in which water use and wastewater treatment are evaluated with technological integration such as machine learning and data management, reveals how to contribute to targets 6, 9, 12, and 14 within the scope of UNEP 2030 sustainable development goals.

To investigate the adsorption behaviour and inhibitive effect of Vigna unguiculata (VU) extract (agricultural waste material) for aluminium corrosion in 0.5 M NaOH and H₂SO₄.

The inhibitive effect of the plant extract was assessed using weight loss method at 30 and 60^oC. The trend of inhibition efficiency with temperature was used to propose the mechanism of inhibition and type of adsorption.

VU extract effectively inhibited aluminium corrosion in both alkaline and acidic media. Inhibition efficiency (I %) of the extract increased with increase in concentration of the extract and temperature. Inhibitor adsorption characteristics were approximated by Freunlich and Temkin adsorption isotherms at all the concentrations and temperatures studied. The phenomenon of chemical adsorption is proposed from the activation parameters obtained.

The mechanistic aspect of the corrosion inhibition can be better understood using electrochemical studies such as polarization and AC impedance spectra.

The findings may be useful in metal surface anodizing and metal coating.

This paper provides new information on the possible application of VU extract as eco‐friendly inhibitor. It has not been reported elsewhere.

To evaluate mild steel corrosion using a new surfactant‐inhibition model which was derived, in part, from the concept of intermolecular energy and molecular separation distance.

A Gamry potentiostat was used for polarization resistance tests to determine corrosion rate and the level of adsorption of surfactant at the solution‐metal interface was determined using UV‐spectroscopy. The relationship between inhibition and surfactant adsorption as well as metal corrosion was investigated using a traditional surfactant‐inhibition model, which assumes inhibition is directly proportional to surfactant coverage and new model.

The comparison of adsorption data and corrosion inhibition data shows inhibition was not directly proportional to physical coverage as assumed by the traditional inhibition model. Instead, it was found that coverage was related to inhibition through a power‐law dependency that is similar to that used to determine molecular interaction energies.

The new model was evaluated only for dodecyl pyridinium chloride mild steel system. The evaluation of the new model for various surfactant‐metal systems is suggested for future research.

The new model was found to more accurately predict the relationship between inhibition and coverage rather than traditional models for dodecyl pyridinium chloride‐mild steel system.