Techno-economic feasibility of a recycling plant for the extraction of metals and boehmite from hazardous petroleum spent catalysts.

Petroleum spent hydroprocessing catalysts are hazardous solid waste, the efficient recycling of which is a serious challenge to refineries. However, information on the economic feasibility of spent catalysts recycling plants is scarce, which is critical for environmental authorities and decision-makers. In this work, an innovative recycling scheme targeting hydrometallurgical recovery of base metals (Ni, Mo, and V) and transforming low-value Al residue into a high-value boehmite (γ-AlOOH) as the key product was considered an efficient way to beneficiate the hazardous spent hydroprocessing catalysts. A preliminary techno-economic evaluation of such a recycling scheme was performed to assess the feasibility of the proposed recycling scheme. The recovery cost (valuable metals and boehmite) and potential revenue were estimated to study the economics of the process. The preliminary results have suggested that the recycling scheme is economically feasible with a high internal rate of return (IRR) of 12.3%, a net present value of 38.6 million USD, and a short payback period of 8.7 years. Furthermore, a sensitivity analysis (± 10%) conducted on key parameters showed that the selling prices of the finished products and the cost of chemicals were the most important factors affecting plant economics. Overall, the recycling scheme was sustainable and avoided landfilling of spent catalysts as the residue can be beneficiated into a high-value product. The results from the economic feasibility study are likely to assist the stakeholders and decision-makers in making investment and policy decisions for the valorization of spent hydroprocessing catalysts.

Post COVID sequelae among COVID-19 survivors: insights from the Indian National Clinical Registry for COVID-19.

INTRODUCTION: The effects of COVID-19 infection persist beyond the active phase. Comprehensive description and analysis of the post COVID sequelae in various population groups are critical to minimise the long-term morbidity and mortality associated with COVID-19. This analysis was conducted with an objective to estimate the frequency of post COVID sequelae and subsequently, design a framework for holistic management of post COVID morbidities. METHODS: Follow-up data collected as part of a registry-based observational study in 31 hospitals across India since September 2020-October 2022 were used for analysis. All consenting hospitalised patients with COVID-19 are telephonically followed up for up to 1 year post-discharge, using a prestructured form focused on symptom reporting. RESULTS: Dyspnoea, fatigue and mental health issues were reported among 18.6%, 10.5% and 9.3% of the 8042 participants at first follow-up of 30-60 days post-discharge, respectively, which reduced to 11.9%, 6.6% and 9%, respectively, at 1-year follow-up in 2192 participants. Patients who died within 90 days post-discharge were significantly older (adjusted OR (aOR): 1.02, 95% CI: 1.01, 1.03), with at least one comorbidity (aOR: 1.76, 95% CI: 1.31, 2.35), and a higher proportion had required intensive care unit admission during the initial hospitalisation due to COVID-19 (aOR: 1.49, 95% CI: 1.08, 2.06) and were discharged at WHO ordinal scale 6-7 (aOR: 49.13 95% CI: 25.43, 94.92). Anti-SARS-CoV-2 vaccination (at least one dose) was protective against such post-discharge mortality (aOR: 0.19, 95% CI: 0.01, 0.03). CONCLUSION: Hospitalised patients with COVID-19 experience a variety of long-term sequelae after discharge from hospitals which persists although in reduced proportions until 12 months post-discharge. Developing a holistic management framework with engagement of care outreach workers as well as teleconsultation is a way forward in effective management of post COVID morbidities as well as reducing mortality.

Development of a novel chelation-based recycling strategy for the efficient decontamination of hazardous petroleum refinery spent catalysts.

The conventional hydrometallurgical methods for recycling refinery spent hydroprocessing catalysts are ineffective in simultaneously removing all metals (Ni, V, and Mo) in a single-stage operation. In this study, a novel octadentate chelating agent, diethylenetriaminepentaacetic acid (DTPA-C14H23N3O10), has been proposed for the first time to remove toxic metals (Ni, V, and Mo) in a single stage of operation from an industrial spent atmospheric residue desulfurization (ARDS) catalysts. It was discovered that the efficient formation of metal-DTPA complexes was attained under the optimum experimental conditions (60 °C, stirring - 150 rpm, S/L ration (w/v) of 2.5%, 7.5% DTPA, and medium pH-9) that resulted in the high removal of Mo (83.6%), V (81.3%) and Ni (64.1%) from the spent ARDS catalyst. Kinetic studies suggest that the leaching process followed a semi-empirical Avrami equation (R2 > 0.92), which predicted that the diffusion control reaction controlled the leaching. Species distribution and ecological risk analysis of the remaining metals in the insoluble residue (mostly Al2O3) indicated that the potential bioavailability of the remaining metals (except Ni) was significantly decreased, and residue poses a low ecological and contamination risk (individual contamination factor <1). Furthermore, the textural properties of the residue (BET surface area-103 m2/g and pore volume- 0.49 ml/g) were dramatically improved, suggesting that fresh hydroprocessing catalyst support can be synthesized using the leached residue. Compared to the conventional processes, the proposed chelating process is highly selective, closed-loop, and achieved high metal recovery in a single-stage operation while decreasing the environmental risks of the hazardous spent catalysts.

Fungal bioleaching of metals from refinery spent catalysts: A critical review of current research, challenges, and future directions.

Petroleum refining operations such as hydroprocessing and fluid catalytic cracking (FCC) generate huge quantities of spent catalysts containing toxic and valuable metals (Ni, V, Mo, Co, W, Al, etc.), the management of which is a serious environmental issue. Besides environmental concerns, the different metals present in the spent catalysts are also a valuable commodity to modern industries. Therefore, these spent catalysts also provide an opportunity to use it as a source of value to the refiners. In recent years, a biotechnological based leaching process 'bioleaching' has emerged as a promising eco-friendly technique for the extraction of metals from these refinery spent catalysts. Among various bioleaching agents such as archean, bacterial, or fungi, the process mediated by the fungi (Aspergillus niger, Penicillium simplicissimum, and many others) is gaining attention owing to the high metal extraction ability of the various fungal produced metabolites (organic acids) under moderately acidic conditions. Furthermore, the ability of these fungi to withstand wide process conditions (pH, spent catalyst concentration, substrate types, etc.), high metal toxicity and use of low-cost organic substrate make them an ideal candidate for bioleaching. In this review article, we shed light on the role and mechanisms of fungi involved in extracting different metals from spent hydroprocessing and FCC catalysts. Key process parameters that affect the efficiency of fungal based bioleaching are discussed. The techno-economic challenges associated with the process are elaborated, and the needed future research directions to promote its commercial applications are highlighted. Based on our analysis, it can be argued that the fungi bioleaching has potential, however, some challenges (slower kinetics, and health and safety) should be addressed before the process can be scaled up for the commercial application.

Prevalence and perceptions of infant massage in India: study from Maharashtra and Madhya Pradesh states.

BACKGROUND: Knowledge of the prevailing infant care practices and their effects is important to inform practice and public programs. Infant massage is a traditional practice in India but remains less studied. This study was conducted to study the prevalence and perceptions of infant massage practices in two states of India. METHODS: A total of 1497 caretakers of children under 18 months of age were interviewed in a cross-sectional study at immunisation units of medical schools in Maharashtra (MH) and Madhya Pradesh (MP) states and through home visits in villages in MH during March through August 2018. RESULTS: Infant massage was a prevalent practice (93.8% [95%CI: 92.4,94.9]) in both study states - 97.9%[95%CI:96.9,98.8] in MH and 85.3%[95%CI: 81.9,88.3] in MP - and the prevalence did not vary between male (94.5%) and female (93.5%) infants (p = 0.44). Massage was mostly initiated in the first week of life (82%); it is widely viewed as a traditional practice. It was common to massage the baby once daily (77%), before bathing (77%), and after feeding (57%). Massage was mostly conducted using oils (97%). In MH, preferred oils were a sesame oil-based proprietary traditional medicine oil (36%) and coconut oil (18%) while olive (29%) and mustard (20%) oils were most popular in MP. Commonly reported application techniques included gentle massage with minimal pressure, pressing (30%) and manually stretching certain joints (60%). Commonly reported perceived benefits of infant massage included increased bone strength, better sleep and growth, while no harm was perceived (95%). CONCLUSION: Infant oil massage is a highly prevalent traditional practice in MH and MP. Clear guidance on the use of massage, choice of oil, and techniques for application is required to optimize benefits and minimize risks of this popular traditional practice.

Infantile tremor syndrome: current perspectives.

Infantile Tremor Syndrome (ITS) is a self-limiting clinical state characterized by tremors, anemia, pigmentary skin disease, regression of mental development, and hypotonia of muscles in a plump looking child. Tremors are coarse in character, decreased or disappeared in sleep and resolves within 4-6 weeks in its natural course. Various etiological factors as infectious, metabolic, nutritional have been hypothesized but none is conclusive. Consensus is developing on the role of Vitamin B12 deficiency in children with ITS but is still debatable. Empirical management of ITS children has been tried in the absence of exact etiology considering child as undernourished. Nutritional management includes supplementation of Iron, Calcium, Magnesium, Vitamin B12 and other multivitamins. Tremors can be managed with administration of propranolol most commonly or phenobarbitone, phenytoin, and carbamazepine.

Metagenomics-Guided Survey, Isolation, and Characterization of Uranium Resistant Microbiota from the Savannah River Site, USA.

Despite the recent advancements in culturomics, isolation of the majority of environmental microbiota performing critical ecosystem services, such as bioremediation of contaminants, remains elusive. Towards this end, we conducted a metagenomics-guided comparative assessment of soil microbial diversity and functions present in uraniferous soils relative to those that grew in diffusion chambers (DC) or microbial traps (MT), followed by isolation of uranium (U) resistant microbiota. Shotgun metagenomic analysis performed on the soils used to establish the DC/MT chambers revealed Proteobacterial phyla and Burkholderia genus to be the most abundant among bacteria. The chamber-associated growth conditions further increased their abundances relative to the soils. Ascomycota was the most abundant fungal phylum in the chambers relative to the soils, with Penicillium as the most dominant genus. Metagenomics-based taxonomic findings completely mirrored the taxonomic composition of the retrieved isolates such that the U-resistant bacteria and fungi mainly belonged to Burkholderia and Penicillium species, thus confirming that the chambers facilitated proliferation and subsequent isolation of specific microbiota with environmentally relevant functions. Furthermore, shotgun metagenomic analysis also revealed that the gene classes for carbohydrate metabolism, virulence, and respiration predominated with functions related to stress response, membrane transport, and metabolism of aromatic compounds were also identified, albeit at lower levels. Of major note was the successful isolation of a potentially novel Penicillium species using the MT approach, as evidenced by whole genome sequence analysis and comparative genomic analysis, thus enhancing our overall understanding on the uranium cycling microbiota within the tested uraniferous soils.

Column bioleaching of metals from refinery spent catalyst by Acidithiobacillus thiooxidans: Effect of operational modifications on metal extraction, metal precipitation, and bacterial attachment.

The feasibility of column bioleaching in the recovery of valuable metals (Ni, V, Mo, and Al) from an uncrushed petroleum refinery spent hydroprocessing catalyst using Acidithiobacillus thiooxidans has been reported. Different operational strategies such as submerged bioleaching in continuous mode, submerged bioleaching in resting period mode, free flow bioleaching in continuous mode, and free flow bioleaching in resting period mode were tested to find out the optimum bioleaching strategy for the recovery of metals from spent hydroprocessing catalyst. Among various operational modifications, submerged bioleaching in continuous mode was considered as the best strategy in which about 82.9% of Ni, 33.4% of Al, and 22.7% of Mo were leached after 315 h of column operation. The maximum yield of V (53.6%) in this column was achieved in 105 h, after which, a rapid decrease in its yield was observed, possibly due to its precipitation. The field emission scanning electron microscopy (FESEM) analysis revealed the presence of V in precipitates. The modified kinetic models showed that the leaching of Al, V and Mo followed the chemical control model, whereas the dissolution of Ni was controlled by diffusion control reaction. The bacterial attachment study with FESEM indicated that the metal toxicity was induced on bacterial cells attached to the sulfur particles. The results of the current study indicate that column bioleaching of spent hydroprocessing catalyst is effective in leaching of Ni and V, whereas leaching of Al and Mo require further treatments.

Novel biogenic synthesis of silver nanoparticles and their therapeutic potential.

Here, we explored the medicinal uses of the novel biogenic silver nanoparticles of Pterospermum acerifolium (PaAgNPs) as a cost effective, eco-friendly, reducing and stabilizing compounds. The formation of PaAgNPs was confirmed by changing its color from colorless to yellowish brown, with maximum absorbance at 417 nm. FTIR spectrum of PaAgNPs suggested the presence of polycyclic compound similar to betulinic acid which plays as a capping agent and provided stability to PaAgNPs. FESEM and HRTEM images depicted the spherical shape of synthesized biogenic silver nanoparticles with an average particle size range of 10-20 nm. The EDX spectrum of the solution confirmed the presence of elemental silver signals. The crystalline nature of PaAgNPs was identified by XRD technique and its stability was recorded using Zeta potential analyzer. The antioxidant potential was assayed using diphenyl-beta-picrylhydrazyl (DPPH). Maximum free radical scavenging action of PaAgNPs was 69.52% as compared to 63.53% for PALE. Using a model of carrageenan-induced paw edema in rats, PaAgNPs showed two-fold enhanced anti-inflammatory activity in vivo.

Synthetic and Natural Monoamine Oxidase Inhibitors as Potential Lead Compounds for Effective Therapeutics.

Monoamine oxidases A and B (MAO-A and B) play a critical role in the metabolism of intracellular neurotransmitters of the central nervous system. For decades, MAO inhibitors have proven their clinical efficacy as potential drug targets for several neurological and neurodegenerative diseases. Use of first generation non selective MAO inhibitors as neuropsychiatric drugs elicited several side effects like hypertensive crisis and cheese reaction. Therefore their use is now limited due to non-selectivity towards MAO isoforms and inhibition of metabolizing enzymes like cytochrome P450. Development of selective and specific MAO inhibitors like moclobemide, toloxatone improves their efficacy as disease-modifying effects in monotherapy as well as adjunctive therapy. Recently a lot of research has been done to elucidate the pharmacological potential of medicinal plants and their isolated bioactive constituents having MAO inhibitory activity. Herbs containing MAO inhibitors are extensively used for the development of potent synthetic drugs and as safe and effective alternatives to the available synthetic drugs in the treatment of neurodegenerative diseases such as depression, Parkinson and Alzheimer's. In several diseases like Parkinson natural MAO inhibitors prevented the neuron denaturalization by their dual action via enhancing neurotransmission of dopamine as well as lowering the generation of free radicals and toxins. Currently development of selective MAO inhibitors is still under study to achieve more effective therapies by using Computer Aided Drug Designing, Ligand-based models and structure-activity hypothesis. These approaches also facilitate understanding the interaction of newly designed molecule with MAO enzymes and the rationalization of probable mechanisms of action.

Optimization of two-step bioleaching of spent petroleum refinery catalyst by Acidithiobacillus thiooxidans using response surface methodology.

A central composite design (CCD) combined with response surface methodology (RSM) was employed for maximizing bioleaching yields of metals (Al, Mo, Ni, and V) from as-received spent refinery catalyst using Acidithiobacillus thiooxidans. Three independent variables, namely initial pH, sulfur concentration, and pulp density were investigated. The pH was found to be the most influential parameter with leaching yields of metals varying inversely with pH. Analysis of variance (ANOVA) of the quadratic model indicated that the predicted values were in good agreement with experimental data. Under optimized conditions of 1.0% pulp density, 1.5% sulfur and pH 1.5, about 93% Ni, 44% Al, 34% Mo, and 94% V was leached from the spent refinery catalyst. Among all the metals, V had the highest maximum rate of leaching (Vmax) according to the Michaelis-Menten equation. The results of the study suggested that two-step bioleaching is efficient in leaching of metals from spent refinery catalyst. Moreover, the process can be conducted with as received spent refinery catalyst, thus making the process cost effective for large-scale applications.

Bioleaching of metals from spent refinery petroleum catalyst using moderately thermophilic bacteria: effect of particle size.

The present work investigated the leaching potential of moderately thermophilic bacteria in the recovery of metals from spent petroleum catalyst of varying particle sizes. The batch bioleaching experiments were conducted by employing a mixed consortium of moderate thermophilic bacteria at 45°C and by using five different particle sizes (from 45 to >2000 µm) of acetone-washed spent catalyst. The elemental mapping by FESEM confirmed the presence of Al, Ni, V and Mo along with sulfur in the spent catalyst. During bioleaching, Ni (92-97%) and V (81-91%) were leached in higher concentrations, whereas leaching yields of Al (23-38%) were found to be lowest in all particle sizes investigated. Decreasing the particle size from >2000 µm to 45-106 µm caused an increase in leaching yields of metals during initial hours. However, the final metals leaching yields were almost independent of particle sizes of catalyst. Leaching kinetics was observed to follow the diffusion-controlled model showing the linearity more close than the chemical control. The results of the present study suggested that bioleaching using moderate thermophilic bacteria was highly effective in removing the metals from spent catalyst. Moreover, bioleaching can be conducted using spent catalyst of higher particle size (>2000 µm), thus saving the grinding cost and making process attractive for larger scale application.

6-Oxo and 6-thio purine analogs as antimycobacterial agents.

6-Oxo and 6-thio analogs of purine were prepared based on the initial activity screening of a small, diverse purine library against Mycobacterium tuberculosis (Mtb). Certain 6-oxo and 6-thio-substituted purine analogs described herein showed moderate to good inhibitory activity. N(9)-substitution apparently enhances the anti-mycobacterial activity in the purine series described herein. Several 2-amino and 2-chloro purine analogs were also synthesized that showed moderate inhibitory activity against Mtb.

Adherence to treatment guidelines for acute diarrhoea in children up to 12 years in Ujjain, India--a cross-sectional prescription analysis.

BACKGROUND: Diarrhoea accounts for 20% of all paediatric deaths in India. Despite WHO recommendations and IAP (Indian Academy of Paediatrics) and Government of India treatment guidelines, few children suffering from acute diarrhoea in India receive low osmolarity oral rehydration solution (ORS) and zinc from health care providers. The aim of this study was to analyse practitioners' prescriptions for acute diarrhoea for adherence to treatment guidelines and further to determine the factors affecting prescribing for diarrhoea in Ujjain, India. METHODS: This cross-sectional study was conducted in pharmacies and major hospitals of Ujjain, India. We included prescriptions from all practitioners, including those from modern medicine, Ayurveda, Homeopathy as well as informal health-care providers (IHPs). The data collection instrument was designed to include all the possible medications that are given for an episode of acute diarrhoea to children up to 12 years of age. Pharmacy assistants and resident medical officers transferred the information regarding the current diarrhoeal episode and the treatment given from the prescriptions and inpatient case sheets, respectively, to the data collection instrument. RESULTS: Information was collected from 843 diarrhoea prescriptions. We found only 6 prescriptions having the recommended treatment that is ORS along with Zinc, with no additional probiotics, antibiotics, racecadotril or antiemetics (except Domperidone for vomiting). ORS alone was prescribed in 58% of the prescriptions; while ORS with zinc was prescribed in 22% of prescriptions, however these also contained other drugs not included in the guidelines. Antibiotics were prescribed in 71% of prescriptions. Broad-spectrum antibiotics were prescribed and often in illogical fixed-dose combinations. One such illogical combination, ofloxacin with ornidazole, was the most frequent oral antibiotic prescribed (22% of antibiotics prescribed). Practitioners from alternate system of medicine and IHPs are significantly less likely (OR 0.13, 95% CI 0.04-0.46, P = 0.003) to prescribe ORS and zinc than pediatricians. Practitioners from 'free' hospitals are more likely to prescribe ORS and zinc (OR 4.94, 95% CI 2.45-9.96, P < 0.001) and less likely to prescribe antibiotics (OR 0.01, 95% CI 0.01-0-04, P < 0.001) compared to practitioners from 'charitable' hospitals. Accompanying symptoms like the presence of fever, pain, blood in the stool and vomiting significantly increased antibiotic prescribing. CONCLUSION: This study demonstrated low adherence to standard treatment guidelines for management of acute diarrhoea in children under 12 years in Ujjain, India. Key public health concerns were the low use of zinc and the high use of antibiotics, found in prescriptions from both specialist paediatricians as well as practitioners from alternate systems of medicine and informal health-care providers. To improve case management of acute diarrhoea, continuing professional development programme targeting the practitioners of all systems of medicine is necessary.

Bioleaching of heavy metals from sewage sludge by indigenous iron-oxidizing microorganisms using ammonium ferrous sulfate and ferrous sulfate as energy sources: a comparative study.

The potential of indigenous iron-oxidizing microorganisms enriched at initial neutral pH of the sewage sludge for bioleaching of heavy metals was investigated at initial neutral pH of the sludge using ammonium ferrous sulfate (FAS) and ferrous sulfate (FS) as an energy sources in two different sets of experiments. After 16 days of bioleaching, 56% Cu, 48% Ni, 68% Zn and 42% C were removed from the sludge using ammonium ferrous sulfate as an energy source. On the other hand, 64% Cu, 58% Ni, 76% Zn and 52% Cr were removed using ferrous sulfate. Further, 32% nitrogen and 24% phosphorus were leached from the sludge using ferrous sulfate, whereas only 22% nitrogen and 17% phosphorus were removed using ammonium ferrous sulfate. The BCR sequential extraction study on speciation of metals showed that using ammonium ferrous sulfate and ferrous sulfate, all the metals remained in bioleached sludge as stable form (F4 fraction). The results of the present study indicate that the bioleached sludge would be safer for land application. Also, the fertilizing property was largely conserved in the bioleached sludge using both the substrates.

Persistent hyperinsulinemic hypoglycemia of infancy--successful therapy with nifedipine.

Recent studies have demonstrated a role for calcium channel blocking agents in the treatment of persistent hyperinsulinemic hypoglycemia of infancy. We report a 30 day old infant with PHHI whom we successfully treated with oral nifedipine alone.