Thermal treatment for the separation of phosphate and recovery of rare earth metals (REMs) from Korean monazite

Kumari, Archana,Panda, Rekha,Jha, Manis Kumar,Lee, Jin Young,Kumar, J. Rajesh,Kumar, Vinay Elsevier 2015 Journal of industrial and engineering chemistry Vol.21 No.-

<P><B>Abstract</B></P> <P>Systematic study for thermal decomposition of monazite to remove phosphate as a valuable product using Na<SUB>2</SUB>CO<SUB>3</SUB> and NaOH roasting processes to validate the TG/DTA studies is reported here. Monazite in 1:1wt. ratio with Na<SUB>2</SUB>CO<SUB>3</SUB> and NaOH requires a temperature of 900°C and 400°C, respectively, for 120min in order to achieve complete conversion of rare earth phosphate into its oxides. The roasted mass was washed, dried and leached in 6M HCl for 2h, pulp density 30g/L at 80°C which results in >90% REMs recovery. Leach liquor generated will be further processed by solvent extraction and precipitation processes.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Effective process for separation and recovery of rare earth metals. </LI> <LI> Alkaline thermal treatment under optimized condition is used to dephosphorize monazite. </LI> <LI> 99% phosphate was separated and recovered as value added product of sodium tri-phosphate. </LI> <LI> The oxide of rare earth concentrate was leached in chloride medium to recover high percentage of rare earth metals. </LI> </UL> </P>

Thermal treatment for the separation of phosphate and recovery of rare earth metals (REMs) from Korean monazite

Archana Kumari,Rekha Panda,Manis Kumar Jha,이진영,J. Rajesh Kumar,Vinay Kumar 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.21 No.1

Systematic study for thermal decomposition of monazite to remove phosphate as a valuable productusing Na2CO3 and NaOH roasting processes to validate the TG/DTA studies is reported here. Monazite in1:1 wt. ratio with Na2CO3 and NaOH requires a temperature of 900 8C and 400 8C, respectively, for120 min in order to achieve complete conversion of rare earth phosphate into its oxides. The roastedmass was washed, dried and leached in 6 M HCl for 2 h, pulp density 30 g/L at 80 8C which results in>90% REMs recovery. Leach liquor generated will be further processed by solvent extraction andprecipitation processes.

Treatment of monazite processed effluent to recover rare earth metals (REMs)

Archana Kumari,Sunidhi Singh,Kavita Parmar,Devendra Deo Pathak,Manis Kumar Jha 한국공업화학회 2020 Journal of Industrial and Engineering Chemistry Vol.83 No.-

Improper disposal of effluent generated in rare earth mining areas and ore processing industries resultsin loss of REMs and miserably affects the ecosystem. Thus, their appropriate treatment is required, whichcan be achieved via environmentally feasible processes. In this connection, systematic scientificadsorption studies were carried out to separate REMs using cationic resin, Amberlite IR120 Na from theeffluent generated during monazite processing for REMs recovery. To optimize feasible conditions forREMs recovery, bench scale studies were carried out varying different process parameters viz. pH, contacttime, resin dose, etc. It was observed that adsorption of 92.63% La, 92.79% Ce, 91.45% Nd, 90.95% Pr and95.09% Sm was achieved at aqueous/ resin (A/R) ratio 25 mL/g, pH 1.3 and contact time 10 min. Loadingcapacity of resin was found to hold 48.57 mg REMs/g resin. The adsorption data followed the second orderreaction ((t/q) = (1/h) + (1/qe)(t)) and Langmuir adsorption isotherm (1/q = [(1/k1 qm)(1/Ce)] + (1/qm)). The loaded REMs was effectively eluted using 15% H2SO4 in 10 min. The REMs enriched solution wastreated to get pure REM oxides as precipitate. This technical application will be useful for REMs recoveryas well as to mitigate environmental pollution.

Effectiveness of Levonorgestrel Releasing Intrauterine System in Perimenopausal Women with Heavy Menstrual Bleeding: A Prospective Study at a Teaching Hospital in India

Nidhi,Archana Kumari,Sarita Tirkey,Jay Prakash 대한폐경학회 2022 대한폐경학회지 Vol.28 No.3

Objectives: To evaluate the effect of levonorgestrel-releasing intrauterine system (LNG-IUS) on heavy menstrual bleeding in perimenopausal women.Methods: This was a prospective, observational clinical study conducted on 42 perimenopausal women with heavy menstrual bleeding who met the study eligibility criteria. LNG-IUS was inserted in the postmenstrual phase following baseline evaluation. The patients were followed up at the 4, 12, and 24 weeks. Pictorial blood assessment chart (PBAC) score, hemoglobin and serum ferritin levels, and endometrial thickness were assessed before insertion and during the follow-up visits. Results: Two patients (4.8%) were lost to follow-up, three patients (7.1%) opted for hysterectomy, two women (4.8%) experienced spontaneous expulsion and 35 (83.3%) women continued the usage. Menstrual blood loss assessed using the median PBAC score (interquartile range) significantly reduced (P < 0.001) from the pre-insertion level of 280 (246–306) to 124 (60–200) at 4 weeks to 45 (34–76) at 12 weeks and further to 32 (20–50) at the end of 24 weeks. Simultaneously, a significant (P < 0.001) improvement in the mean hemoglobin and serum ferritin levels and a significant (P < 0.001) decrease in endometrial thickness were observed. The most common side effect was spotting (50.0%) and vaginal discharge (38.1%).Conclusions: LNG-IUS causes a remarkable reduction in menstrual blood loss and marked improvement in dysmenorrhea. It also reduces anemia by improving the hemoglobin and ferritin levels. Thus, it can serve as an effective treatment option for heavy menstrual bleeding in perimenopausal women and prevent the need for a hysterectomy.

Prevalence of Sarcopenic Obesity in Various Comorbidities, Diagnostic Markers, and Therapeutic Approaches: A Review

Mangalam Kumari,Archana Khanna 대한노인병학회 2022 Annals of geriatric medicine and research Vol.26 No.4

The coexistence of sarcopenia and obesity characterizes sarcopenic obesity. In this condition, there is an imbalance between lean and fat mass amounts. It is a prevalent issue that is gaining prevalence among the elderly population. To evaluate the condition, allied health professionals may employ non-invasive diagnostic techniques, such as gait speed, skeletal muscle mass, and muscle strength. Nevertheless, early diagnosis and treatment of pathology are essential for preventing debilitating effects and providing the highest quality of care. This article reviews the prevalence of sarcopenic obesity in numerous medical conditions, such as cancer, arthritis, postoperative cases, diabetes mellitus, obesity, and metabolic syndrome. In addition, this paper aims to examine the available evidence regarding the prevalence of sarcopenic obesity in other conditions along with their diagnostic markers and therapeutic approaches.

Hydrometallurgical processing of waste integrated circuits (ICs) to recover Ag and generate mix concentrate of Au, Pd and Pt

Rekha Panda,Om Shankar Dinkar,Archana Kumari,Rajesh Gupta,Manis Kumar Jha,Devendra Deo Pathak 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.93 No.-

Present research reports a novel and feasible process to recover Ag and generate concentrate of preciousmetals (Au, Pd and Pt) from waste ICs present in PCBs of computers. Initially, depopulated ICs werepulverized and beneficiated to obtain metallic concentrate, which contained (per ton) 7 Kg Ag, 5 Kg Au,110 g Pd and 4 g Pt along with Cu, Pb, Fe and Ni. Leaching was carried out and found that at optimizedcondition i.e. 3 M HNO3, temperature 80 C, pulp density 50 g/L and mixing time 1 h, >90% of Ag, Cu, Pband Ni were leached leaving Au, Pt and Pd in the residue. From the leach liquor, Ag was precipitated using1 M KCl in 30 min and other metals were recovered by precipitation, solvent extraction and cementationmethods. All wastes (solid/ liquid) generated during process development could be treated usingstandard environmental procedure.

Leaching of rare earth metals (REMs) from Korean monazite concentrate

Rekha Panda,Manis Kumar Jha,이진영,Archana Kumari,Jhumki Hait,Vinay Kumar,J. Rajesh Kumar 한국공업화학회 2014 Journal of Industrial and Engineering Chemistry Vol.20 No.4

Systematic scientific studies for dephosphorization and acid leaching of Korean monazite are reported here. 50% NaOH (w/v) solubilizes 99.99% phosphate, at 170 ℃, 100 g/L pulp density in 4 h. Kinetics of phosphate leaching fitted well with model ‘‘chemical reaction control,’’ i.e. 1 - (1 - X)1/2 = kct, Ea = 58.04 kJ/mol. Further, rare earth hydroxides (REHs) was leached using 6 N HCl at 90 ℃, 60 g/L pulp density for 2 h to recover ~95% REMs. Leach liquor generated can be further processed using solvent extraction/ion exchange techniques. From the pure solutions, metal/salts could be obtained using evaporation, precipitation, etc.

Laparoscopic gynecological surgery in COVID-19 pandemic

Kallol Kumar Roy,Rakhi Rai,Rinchen Zangmo,Archana Kumari,Nilofar Noor,Deepali Garg 대한산부인과학회 2021 Obstetrics & Gynecology Science Vol.64 No.3

The major concern that has confronted surgeons during the COVID-19 pandemic is the risk of infection duringsurgery. So far, no studies have found SARS-CoV-2 in surgical smoke, and if it was found, whether it was infectious ornot is unknown. To date, no evidence shows that respiratory viruses can be transmitted through a surgical plume oran aerosolized gas. There are various advantages of laparoscopy over laparotomy that must be kept in mind in theCOVID-19 era, such as early recovery and shorter hospital stay, which can greatly help to conserve valuable hospitalresources, and reduced risk of spillage of blood and body fluids, which can help to reduce transmission risk; mostimportantly, the distance between surgeons and between surgeons and patient is greater. Certain precautionarymeasures can be taken to reduce SARS-CoV-2 transmission during laparoscopy. Whenever possible, it should be thesurgical option of choice.

Role of para-cervical block in reducing immediate postoperative pain after total laparoscopic hysterectomy: a prospective randomized placebo-controlled trial

( Nilofar Noor ),( Kallol Kumar Roy ),( Rinchen Zangmo ),( Anamika Das ),( Rakhi Rai ),( Archana Kumari ),( Deepali Garg ),( Sonam Berwa ),( Sushmita Saha ),( Perumal Vanamail ) 대한산부인과학회 2021 Obstetrics & Gynecology Science Vol.64 No.1

Objective To study the efficacy and safety of 0.5% bupivacaine in paracervical block to reduce immediate postoperative pain after total laparoscopic hysterectomy. Methods A prospective, randomized, double-blind, placebo-controlled study was conducted at a tertiary referral center involving thirty women each in the treatment and placebo groups. Paracervical block with 10 mL of 0.5% bupivacaine (treatment group) or 0.9% saline (placebo group) was administered following general anesthesia and prior to proceeding with total laparoscopic hysterectomy. Visual analogue scale (VAS) scores at 30 and 60 minutes post extubation and mean VAS score (average VAS score at 30 and 60 minutes) were compared. Adequate pain control was defined as mean VAS score ≤5. Additional postoperative opioid requirement, hospital stay, and readmissions were also compared. Results Baseline variables such as age, previous history of cesarean section, operating time, and weight of the specimen were comparable in both groups. VAS scores at 30 (5.0±2.8 vs. 7.0±1.4) and 60 minutes (5.2±2.8 vs. 7.0±0.8) and the mean VAS score (5.1±2.7 vs. 6.8±0.9) were significantly lower in the treatment group. Adequate pain control (mean VAS score ≤5) was 57% higher and additional opioid consumption was 47% lower in the treatment group. No significant difference was found in the duration of hospital stay and readmission rate. Conclusion Paracervical block with bupivacaine was useful in reducing immediate postoperative pain with a 25% reduction in mean VAS score and a 47% reduction in opioid consumption in the first hour after total laparoscopic hysterectomy.

Gynecological laparoscopic surgeries in the era of COVID-19 pandemic: a prospective study

( Sushmita Saha ),( Kallol Kumar Roy ),( Rinchen Zangmo ),( Anamika Das ),( Juhi Bharti ),( Rakhi Rai ),( Archana Kumari ),( Gayatri Suresh ),( Nilofar Noor ),( Perumal Vanamail ) 대한산부인과학회 2021 Obstetrics & Gynecology Science Vol.64 No.4

Objective The novel coronavirus pandemic led to the suspension of elective surgeries and the diversion of resources and manpower towards pandemic control. However, gynecological emergencies and malignancies must be addressed despite the restricted resources and the need for protective measures against COVID-19. This study aimed to determine the types of gynecological surgeries performed, difficulties encountered, and their outcomes in the setting of the pandemic. Methods We performed a prospective cohort study over 6 months at a single tertiary center, including 60 women with gynecological complaints, categorized as emergencies and semi-emergencies, who underwent further surgery. Their surgical outcomes were measured through various parameters. Results We found that 68.3% were emergency cases, while the rest were classified as semi-emergencies. Fibroid and adenomyosis with failed medical management (48.3%), followed by cervical intraepithelial neoplasia (10%), and malignancies (10%) accounted for the semi-emergency cases, while ruptured ectopic pregnancies (13.3%) and torsion and ovarian cysts (18.4%) comprised the emergency cases. The decision to incision time between emergency and semi-emergency cases varied widely due to the safety prerequisites during the pandemic, ranging from 1 hour in emergency cases to 48 hours in semi-emergency cases. In addition, we studied the ease of preoperative preparation, patient satisfaction, and the average number of personnel available to run the operation theaters at these times. No serious perioperative adverse events were observed in the present study. Conclusion In conclusion, gynecological surgeries could continue to be safely performed with all precautions in place against COVID-19 infection and related morbidities.