scholarly journals Recent Advances in Biomass-Based Waste Materials for the Removal of Chromium (VI) from Wastewater: A Review

2021 ◽  
Vol 2 (01) ◽  
pp. 37-50
Author(s):  
Rajan Rai ◽  
Dirgha Raj Karki ◽  
Krishna Prasad Bhattarai ◽  
Bishnu Pahari ◽  
Nabina Shrestha ◽  
...  
Keyword(s):  
Literature Review ◽  
Adsorption Capacity ◽  
Environmentally Benign ◽  
Waste Materials ◽  
Health Issues ◽  
High Toxicity ◽  
Chemically Modified ◽  
Chromium Vi ◽  
Modified Adsorbents ◽  
Trace Concentrations

Hexavalent chromium (Cr(VI)) is a critical pollutant with high toxicity, even at trace concentrations. Cr(VI) is possibly carcinogenic and mutagenic and can produce serious health issues. Hence, it is necessary to remove Cr(VI) from the water before releasing it into the environment. Currently, numerous removal techniques were used. Adsorption is the best method compared to others because it is simple, cheap, highly efficient, and can be used in water having trace concentrations of contaminants. Biomass-based waste materials (BMWs) are found as far better adsorbents than commercially and other available adsorbents. In this study, the existing Cr(VI) removal techniques are reviewed and, a broad range of current research studies of Cr(VI) removal from water by using BMWs are evaluated. This review can be helpful to develop a more efficient, cheap, reliable, and environmentally benign bio-adsorbent. It is obvious after the literature review given herein that BMWs exhibited potential adsorbents for the removal of Cr(VI). Also, the chemically modified adsorbents exhibited a higher adsorption capacity than unmodified adsorbents.

scholarly journals Optimizing modified rice bran for treating aqueous solutions polluted by Cr (VI) ions: isotherm and kinetics analyses

2021 ◽  
Vol 13 (SP1) ◽  
pp. 1-11
Author(s):  
Zahra Ameri ◽  
Mehran Hoodaji ◽  
Majid Rajaei ◽  
Mitra Ataabadi
Keyword(s):  
Removal Efficiency ◽  
Rice Bran ◽  
Freundlich Isotherm ◽  
Contact Duration ◽  
Isotherm Equation ◽  
Chemically Modified ◽  
Ph Values ◽  
Chromium Vi ◽  
Pseudo Second Order ◽  
Modified Adsorbents

This study investigated the possibility and efficiency of absorbing chromium (VI) (Cr [VI]) ions from the polluted solutions by employing the chemically modified adsorbents (alkali, biochar, and acid rice bran), focusing on the possible impacts of the solution’s pH values, adsorbent’s dosages, concentrations, and contact times. The colori-metric method was used for Cr determination by employing an ultraviolet/visible spectrophotometer. The scanning electron microscope and Fourier transform infrared spectroscopy were used to analyze the characteristics of the modified adsorbents. The findings indicated that the optimized acid, biochar, alkali, and unmodified rice bran removal efficiency for Cr (VI) were 94.50%, 94.27%, 88.60%, and 90.18%, respectively. The increase of adsorbent dosage up to 2 g/L led to a rise in removal effectiveness (82.06%). Furthermore, the highest removal efficiency was obtained (94%) at the pH of 2.0, the contact duration of 100 min, Cr (VI) concentration of 50 mg/L, and dosage of 2 g/L, which was statistically the optimal condition for the modified rice bran. The adsorption kinetics was agreeably suited to pseudo-second-order, whereas the Freundlich isotherm equation was also suitably expounded the study’s findings. The findings implied that the acid and biochar rice bran performed remarkably in the reme-diation of the wastewater compared with alkali rice bran for reuse for industrial, agricultural, and environmental purposes.

Reproductive health issues in patients with psoriasis (literature review)

2019 ◽  
Vol 1 (7) ◽  
pp. 5-8
Author(s):  
L. S. Kruglova ◽  
A. A. Osina ◽  
A. A. Khotko
Keyword(s):  
Drug Therapy ◽  
Reproductive Health ◽  
Literature Review ◽  
Pregnancy Outcomes ◽  
Adverse Pregnancy Outcome ◽  
Certolizumab Pegol ◽  
Genetically Engineered ◽  
Health Issues ◽  
Degree Of Confidence ◽  
Adverse Pregnancy

Among patients with psoriasis, approximately 50% are women and almost 75 % of them are under the age of 40 years. Thus, most women with psoriasis have childbearing potential. When pregnancy occurs in 22 % of patients, the activity of psoriasis persists, characteristic of the course before pregnancy, in 23 % of women, the course of the disease worsens. The article provides up-to-date data on the management of pregnant patients with psoriasis. To improve pregnancy outcomes in patients with psoriasis, it is important to prevent exacerbation of the disease. The choice of drug therapy in this case is based on an assessment of the ratio of the risk of undesirable effects of the drugs on the developing fetus and the risk of the development of exacerbation of psoriasis, which can cause an adverse pregnancy outcome. Despite the fact that the available clinical experience of using genetically engineered drugs is still limited, with a certain degree of confidence we can say that there is no increase in the risk of adverse pregnancy outcomes associated with therapy with certolizumab pegol.

Reproductive health issues in female patients with beta-thalassaemia major: a narrative literature review

2020 ◽  
Vol 40 (7) ◽  
pp. 902-911 ◽  
Author(s):  
Malihe Nourollahpour Shiadeh ◽  
Elena Cassinerio ◽  
Maryam Modarres ◽  
Armin Zareiyan ◽  
Zeinab Hamzehgardeshi ◽  
...  
Keyword(s):  
Reproductive Health ◽  
Literature Review ◽  
Thalassaemia Major ◽  
Health Issues ◽  
Female Patients ◽  
Beta Thalassaemia ◽  
Narrative Literature ◽  
Narrative Literature Review

scholarly journals Optimization of cadmium(II) adsorption onto modified and unmodified lignocellulosics (rice husk and egussi peeling)

2015 ◽  
Vol 5 (1) ◽  
pp. 45
Author(s):  
Tchuifon Tchuifon Donald Raoul ◽  
Nche George Ndifor-Angwafor ◽  
Ngakou Sadeu Christian ◽  
Kamgaing Théophile ◽  
Ngomo Horace Manga ◽  
...  
Keyword(s):  
Adsorption Capacity ◽  
Rice Husk ◽  
Order Kinetic ◽  
Adsorption Model ◽  
Batch Technique ◽  
Order Kinetic Model ◽  
Pseudo Second Order ◽  
Adsorbed Quantity ◽  
Minimal Mass ◽  
Modified Adsorbents

<p>The present study is based on the adsorption of cadmium (II) ions on rice husk and egussi peeling, unmodified and modified with nitric acid in aqueous solution, using batch technique. It was carried out as a function of contact time, dosage, pH and initial concentration. The equilibrium time was achieved within 25 minutes for unmodified rice husk (Glu NT) and 20 minutes for unmodified egussi peeling (Cuc NT) with an adsorbed quantity of 13.18 mg/g. In the case of modified materials, we obtained 15 minutes for modified rice husk (Glu HNO3) and 10 minutes for modified egussi peeling (Cuc HNO3) with an adsorbed quantity of 18.77 mg/g. The maximum biosorption occurred at pH 5.5 for all biosorbents. The adsorbent mass for maximum adsorption was 0.4 g giving an adsorption capacity of 62.02 % for unmodified adsorbents. In the case of modified adsorbents, the minimal mass at which maximum adsorption occurred was 0.4 g giving an adsorption capacity of 98.33 % and 0.6 g giving an adsorption capacity of 98.33 % for modified rice husk and egussi peeling respectively. The adsorbent/adsorbate equilibrium was well described by the pseudo-second order kinetic model and by Langmuir’s and Freundlich adsorption model. This models showed that the adsorption of cadmium (II) is a chemisorption process.</p>

scholarly journals Removal of Chromium (VI) from Aqueous Solution Using Chemically-Modified Sweet Lime (Citrus limetta) Peels as Adsorbent

2017 ◽  
Vol 36 ◽  
pp. 82-95
Author(s):  
Devi Lal Adhikari ◽  
Ram Lochan Aryal ◽  
Sitaram Bhattarai ◽  
Surendra Kumar Gautam ◽  
Bhoj Raj Poudel
Keyword(s):  
Aqueous Solution ◽  
Full Text ◽  
Chemically Modified ◽  
Chromium Vi ◽  
Sweet Lime ◽  
Citrus Limetta

available with full text

scholarly journals Educação ambiental e em saúde com escolares: outros rumos para a enfermagem [Environmental and health education for schoolchildren: other directions for nursing] [Educación ambiental y en salud con estudiantes: otros rumbos para la enfermería]

2017 ◽  
Vol 25 ◽  
pp. e26182
Author(s):  
Crystiane Ribas Batista Ribeiro ◽  
Vera Maria Saboia ◽  
Donizete Vago Daher ◽  
Fabiana Ferreira Koopmans
Keyword(s):  
Environmental Education ◽  
Literature Review ◽  
Behavioral Change ◽  
Knowledge Construction ◽  
Scientific Production ◽  
Health Educators ◽  
Health Issues ◽  
Environment And Health ◽  
The Social ◽  
Systematic Knowledge

Objetivo: sintetizar a produção científica sobre educação ambiental com escolares estabelecendo uma interface com a saúde humana. Método: estudo de revisão integrativa da literatura, realizado em 2016, que contemplou as bases de dados: LILACS, SciELO, MEDLINE, BDENF e PubMed, Resultados: foram examinados 11 artigos científicos publicados no período de 2012-2016. Evidenciou-se a educação ambiental atrelada à possibilidade de transformação e mudança de comportamento, ressaltando-se a perspectiva social/cívica. Identificou-se ainda que os escolares possuem conhecimento sistematizado sobre meio ambiente no tocante a sua preservação, porém sem associação com a saúde. Além disso, não foi observada preocupação dos estudantes em relacionar questões de saúde ao contexto em que estão inseridos. Conclusão: tendo em vista a responsabilidade do enfermeiro como agente educador em saúde em nível planetário, salienta-se a necessidade de projetos socioambientais que articulem a relação homem/ambiente/saúde de modo que a construção do saber seja colaborativa, extensiva à escola, família e comunidade local. ABSTRACTObjective: to summarize the scientific production on environmental education for schoolchildren establishing an interface with human health. Method: this integrative literature review was conducted in 2016 in the LILACS, SciELO, MEDLINE, BDENF and PubMed databases. Results: review of 11 articles published between 2012 and 2016 revealed environmental education linked to the possibility of transformation and behavioral change, and highlighting the social/civic perspective. Schoolchildren were also found to have systematic knowledge about the environment as to preservation, but unassociated with health. In addition, the schoolchildren were unconcerned to relate health issues to the context in which they occur. Conclusion: in view of nurses’ responsibility as health educators planet-wide, there is a clear need for socio-environmental projects that interrelate humankind, environment and health in such a manner that the knowledge construction is collaborative, and involves school, family and local community.RESUMENObjetivo: sintetizar la producción científica sobre educación ambiental con estudiantes estableciendo una interfaz con la salud humana. Método: estudio de revisión integrativa de literatura, realizado en 2016, que contempló las bases de datos LILACS, SciELO, MEDLINE, BDENF y PubMed. Resultados: se examinaron 11 artículos científicos publicados en el período 2012-2016. Se evidenció la educación ambiental vinculada a la posibilidad de transformación y cambio de comportamiento, resaltando la perspectiva social/cívica. Se identificó además que los estudiantes poseen conocimiento sistematizado sobre medio ambiente en cuanto a su preservación, pero sin asociación con la salud. Además, no se observó una preocupación por parte de los estudiantes en relacionar cuestiones de salud con el contexto en que están insertados. Conclusión: teniendo en cuenta la responsabilidad del enfermero como agente educador en salud a nivel planetario, se resalta la necesidad de proyectos socioambientales que articulen la relación hombre/ambiente/salud de modo que la construcción del saber sea colaborativa, extensiva a la escuela, la familia y la comunidad local. DOI: http://dx.doi.org/10.12957/reuerj.2017.26182

scholarly journals Effect of Modified Eggshell on Adsorption Capacity of Chromium(VI) from Aqueous Solution

2020 ◽  
Vol 32 (7) ◽  
pp. 1549-1556
Author(s):  
Abdulaziz Ali Alomari
Keyword(s):  
Aqueous Solution ◽  
Thermal Treatment ◽  
Adsorption Capacity ◽  
Rhombohedral Structure ◽  
Chromium Vi ◽  
Protein Fibers ◽  
Residual Protein ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order ◽  
Static Conditions

The aim of this work is to investigate the use of eggshell for adsorption of Cr(VI) from aqueous solution and the effect of thermal treatment as well as coating with Fe2O3 of eggshell on the extraction percent of Cr(VI). The XRD, FTIR and SEM techniques proved that the eggshell mainly composed of calcite rhombohedral structure in addition to a trace of quartz silica residual protein fibers. Heating at 550 ºC does not decompose eggshell but decomposes the residual protein. The effect of pH, weight of eggshell adsorbent, contact time, and initial concentration of Cr(VI) ions on the adsorption of Cr(VI) on eggshell sorbents were determined under static conditions by the batch equilibrium technique. The sorption kinetic as well as mechanistic isotherm parameters of Cr(VI) on the eggshell sorbent, were analyzed. It was concluded that the adsorption of Cr(VI) on eggshell increases as pH increases in the range 3-7, then, with decreases at higher pH. The extraction percent of Cr(VI) increases with an increase in the dosage of eggshell sorbents. The optimum dosage of eggshell adsorbents was found to be 5 g after which the extraction percent of Cr(VI) did not marked increase. The extraction percent of Cr(VI) by eggshell sorbents rapidly increases within 60 min followed by a slower extraction after that when maximum adsorption was reported. The adsorption capacity of Cr(VI) ions is slightly reduced in case of heated eggshell due to the change that occurs in the pore size distribution and structure of eggshell during heating. Hence, the thermal treatment and coating with Fe2O3 do not affect the chemical structure of eggshell sorbents. The adsorption kinetics data were best fitted with the pseudo-second-order equation and the adsorption isotherms were best fitted with the Langmuir isotherm model.

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