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Showing 4 results for Separation

B. Kakavandi, M. Mokhtari, R. Rezaee Kalantari, E. Ahmadi, N. Rastkari, M. Fatehi, A. Azari,
Volume 7, Issue 3 (5-2014)
Abstract

Background and Objectives: Phenol is one of priority pollutants produced through leather, paint, resin, and pharmaceutical industries and it can contaminate groundwater after entering to the environment. Hence, it is necessary to use a suitable method for its removal. The aim of this study was synthesize and efficiency evaluation of magnetic nanocomposite of activated carbon powder-zero valent iron/silver (PAC-Feo/Ag) in the removal of phenol from aqueous solution. Material & Methods: Reduction method was used for converting bivalent iron to zero valent iron and co-precipitation method for depositing of iron on activated carbon. For coating silver on nano zero valent iron, rapid mixing at high temperature was used. The adsorbent was characterized using SEM, TEM, and XRD techniques. Then, the impact of pH, contact time, agitation speed, temperature, adsorbent, and initial phenol concentration were evaluated and optimized by one factor at the time method. Reaction kinetics and isotherms were also determined. Results: It was found that PAC-Feo/Ag has cubic and intertwined structure and has a diameter in the range from 40 to 100 nm. The optimum conditions for phenol removal by PAC-Feo/Ag were as pH=3, 90 min contact time, 200 rpm agitating speed and adsorbent concentration equal to 1 g/l. Isotherm and kinetic equations showed that the experimental data of phenol adsorption onto PAC-Feo/Ag are correlated to the Langmuir (R2>0.969) and pseudo-second order (R2<0.965) models, respectively. Conclusion: Under optimum conditions, modified adsorbent by zero valent iron and silver with maximum efficiency of 97% has quickly and effectively ability in removal of phenol and it can be easily separated from the solution sample by magnet because of its magnetic properties.


J Karimi, M Sadeghi, E Fadaie, M.h Mehdinejad,
Volume 8, Issue 3 (12-2015)
Abstract

Background and Objective: Collection and disposal of waste has an important role in public health. Isolation and separation procedures at the origin is considered as one of the most important and least costly methods of isolation and separation of waste. This study was aimed to culture and educate those involved in recycling and waste reduction in the Kalaeh City using two educational methods. .

Materials and Methods:  This semi-experimental study was conducted in Kalaleh City. In the social and cultural context,   Kalaleh was divided into six regions. Using cluster sampling, regions were selected randomly. In each area, 120 samples were used. The first group was face-to-face trained and the second group received training through the training package. Waste collection period was 60 days. After this time, the questionnaires were again filled up  and the impact of teaching methods were investigated.

Results: Face-to-face training resulted in increasing waste separation from 70.8 (before training) to 95%. Whereas, this figure in the group receiving training package increased from 57.5 (before training) to 86.7%. Waste recycling rate was between 0.6 to 1 Kg per person per week. These wastes included paper, glass, plastic, and metal containers. On average, the waste recycled in face-to-face training group and training package group was  91 and 83 Kg per week.

Conclusion: Knowledge, attitude and cooperation in waste separation increased after training in both groups. However, in the face-to-face training group, the knowledge and participation in waste separation was more compared with training package group. Continuous training and organizing waste separators could be helpful to re-use waste. It causes less pollution of the environment, reduce the transmission of diseases associated with non-systematic disposal of solid waste, reduce costs and increase awareness about the problems and issues of solid waste, and reduce the solid waste volume.


Sakine Shekoohiyan, Mobina Hadadian, Mohsen Heidari,
Volume 14, Issue 3 (12-2021)
Abstract

Background and Objective: Changes in the quantity and quality of waste produced as a result of compliance with health protocols are the result of the COVID-19 outbreak. The present study aimed to determine the quantity of personal protection equipment produced in Tehran and people’s knowledge of its management.
Materials and Methods: The present cross-sectional and descriptive-analytical study was carried out on 2560 participants in Tehran through an online survey in spring 2020. Based on the percentage of using masks and gloves, the amount of produced waste was calculated, and Mann-Whitney and Kruskal-Wallis statistical tests were run to explore the relationship between the variables.
Results: The overall Cronbach's alpha coefficient of the questionnaire was 0.94, and the rate of mask and glove use was 90.7% and 65.7%, respectively. 70.3% and 52% of the population used two masks and one pair of gloves on a daily basis. The number of daily produced masks and pairs of gloves was 14530407 and 5262666, respectively. Mann-Whitney U-test showed a statistically significant difference between gender and marital status with people’s knowledge of waste management (p <0.05). Kruskal-Wallis test showed a significant difference between the economic status and people’s knowledge of separating the produced waste (p <0.05). People with an increasing income tended to separate the waste more.
Conclusion: Due to the high volume of personal protective wastes and the lacking knowledge of one-third of the participants about the transmission of the virus through contaminated waste, it is necessary to raise awareness of breaking the virus transmission chain.

Samaneh Dehghan, Mohammad Ali Zazouli, Abolfazl Hosseinnataj, Masoome Sheikhi, Ali Koohi,
Volume 16, Issue 2 (9-2023)
Abstract

Background and Objective: Nowadays, recycling is one of the ways to save mankind from the mass of waste it produces, and waste separation from the source is the first and most important link in the field of urban waste recycling. Since the necessity and basis of recycling is people's participation in separation plans from the source, the present study was conducted to investigate the awareness, attitude, and performance of the people of Mazandaran province regarding the source separation of household waste in 2021.
Materials and Methods: The present study was a descriptive-analytical and cross-sectional study, and the tool used in it was a researcher-made questionnaire including three dimensions of knowledge, attitude, and performance, the link of which was provided online to qualified people. The qualitative content validity of this questionnaire was confirmed by 8 environmental health experts in the field of the research subject. The reliability of the tool was also estimated through the Retest Method. Furthermore, the values of Cronbach's alpha coefficient for the three dimensions of awareness, attitude, and performance were calculated. In the following, the samples were selected in virtual groups based on the available sampling method and through the distribution of the questionnaire link online. Analysis of variance was used to compare the mean scores in the levels of variables, Pearson's correlation test was used to examine the relationship between the scores of awareness, attitude, and performance dimensions, and linear regression was used to examine the effect of independent variables. Finally, the data was analyzed in SPSS software (version 22).
Results: For the entire study population (305 people), the range and mean score of awareness were 0-6, and 5.03±1.18 respectively, the range and mean score of attitude were 17-85 and 61.01± 9.45, and the range and mean score of performance were 6-30 and 11.43±5.19, respectively. Also, there was a significant correlation between the mean scores of the dimensions of awareness and attitude (correlation coefficient=0.70), awareness and performance (correlation coefficient=0.68), and attitude and performance (correlation coefficient=0.63).
Conclusion: The results of this study, which was conducted to measure the knowledge, attitude, and performance of the people of Mazandaran province regarding the separation of household waste from the source and waste recycling, and with a survey of 305 households in this province, showed that although the most of people have a piece of proper knowledge and attitude related to the importance of separation and recycling of solid waste, they have not participated much in the plans of waste separation from the source. Therefore, in order to increase the level of people's performance, it is recommended to develop incentive programs in the field of source separation, including awarding prizes or applying discounts on waste charges, as well as providing suitable containers for waste separation to households for free by the municipality to encourage waste separation.
 


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