scholarly journals Current and Emerging Adsorbent Technologies for Wastewater Treatment: Trends, Limitations, and Environmental Implications

Water ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 215
Author(s):  
Fazila Younas ◽  
Adnan Mustafa ◽  
Zia Ur Rahman Farooqi ◽  
Xiukang Wang ◽  
Sadia Younas ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Cost Benefit ◽  
Cost Effective ◽  
Pollutant Removal ◽  
Future Research ◽  
Environmental Implications ◽  
Treatment Techniques ◽  
Secondary Pollutants ◽  
Other Substances ◽  
Agricultural Materials

Wastewater generation and treatment is an ever-increasing concern in the current century due to increased urbanization and industrialization. To tackle the situation of increasing environmental hazards, numerous wastewater treatment approaches are used—i.e., physical, chemical, and biological (primary to tertiary treatment) methods. Various treatment techniques being used have the risks of producing secondary pollutants. The most promising technique is the use of different materials as adsorbents that have a higher efficacy in treating wastewater, with a minimal production of secondary pollutants. Biosorption is a key process that is highly efficient and cost-effective. This method majorly uses the adsorption process/mechanism for toxicant removal from wastewater. This review elaborates the major agricultural and non-agricultural materials-based sorbents that have been used with their possible mechanisms of pollutant removal. Moreover, this creates a better understanding of how the efficacy of these sorbents can be enhanced by modification or treatments with other substances. This review also explains the re-usability and mechanisms of the used adsorbents and/or their disposal in a safe and environmentally friendly way, along with highlighting the major research gaps and potential future research directions. Additionally, the cost benefit ratio of adsorbents is elucidated.

Conventional to Nano-Green Adsorbents for Water Pollution Management - A Review

2014 ◽  
Vol 925 ◽  
pp. 674-678 ◽  
Author(s):  
Md Eaqub Ali ◽  
Mahbub Ullah ◽  
Sharifah Bee Abd Hamid
Keyword(s):  
Water Pollution ◽  
High Surface ◽  
High Surface Area ◽  
Cost Effective ◽  
Chemical Precipitation ◽  
Surface Reactivity ◽  
Pollutant Removal ◽  
Treatment Techniques ◽  
Water Pollution Management ◽  
Important Position

Pure and clean water is a must for living a healthy life. However, the increasing influence of urbanization, industrialization, domestic and agricultural activities, is continuously adding both conventional and newly emerging pollutants to the earth's water bodies, seriously affecting both the terrestrial and aquatic flora and fauna. Thus water pollution has become a major issue in the global perspectives. In the last few decades, numerous methods, such as chemical precipitation, filtration, oxidation, ion exchange treatment and adsorption have been proposed for the purification of contaminated water. Among these methods, adsorption has taken an important position in water purification technology. This is because of its ease of operations, cost-effective maintenance, and availability of adsorbents in various forms with high surface area, porous structure and specific surface reactivity. Instead of having many attractive properties, many adsorbents have failed to achieve a good acceptability at commercial levels. In the recent years, nanotechnology approaches have introduced nanoadsorbent which is capable of removing water pollutants more efficiently. In this review, various water treatment techniques with their shortcomings followed by efficiency of adsorption and nanoadsorbent for pollutant removal are discussed with green chemistry perspectives.

Physical and Psychological Benefits of Written Emotional Expression

2015 ◽  
Vol 20 (4) ◽  
pp. 242-251 ◽  
Author(s):  
Éva Kállay
Keyword(s):  
Mental Health ◽  
Expressive Writing ◽  
Mental Health Problems ◽  
Cost Effective ◽  
Health Problems ◽  
Future Research ◽  
Psychological Benefits ◽  
Cost Effective Treatment ◽  
Meta Analyses

Abstract. The last several decades have witnessed a substantial increase in the number of individuals suffering from both diagnosable and subsyndromal mental health problems. Consequently, the development of cost-effective treatment methods, accessible to large populations suffering from different forms of mental health problems, became imperative. A very promising intervention is the method of expressive writing (EW), which may be used in both clinically diagnosable cases and subthreshold symptomatology. This method, in which people express their feelings and thoughts related to stressful situations in writing, has been found to improve participants’ long-term psychological, physiological, behavioral, and social functioning. Based on a thorough analysis and synthesis of the published literature (also including most recent meta-analyses), the present paper presents the expressive writing method, its short- and long-term, intra-and interpersonal effects, different situations and conditions in which it has been proven to be effective, the most important mechanisms implied in the process of recovery, advantages, disadvantages, and possible pitfalls of the method, as well as variants of the original technique and future research directions.

Cost Effective Wastewater Treatment by Natural Adsorbent

2018 ◽  
Vol 8 (4) ◽  
pp. 777-785
Author(s):  
Mahmudur Rahman Idris ◽  
Md. Arifuzzaman ◽  
Arnob Basak ◽  
Tonmoy Saha and Jarin Yasmin
Keyword(s):  
Wastewater Treatment ◽  
Cost Effective ◽  
Natural Adsorbent

Cost-effective upgrading of the Arnsberg WWTP by post denitrification with a moving bed system

2000 ◽  
Vol 41 (9) ◽  
pp. 123-130
Author(s):  
N. Jardin ◽  
L. Rath ◽  
A. Sabin ◽  
F. Schmitt ◽  
D. Thöle ◽  
...  
Keyword(s):  
Carbon Source ◽  
Biological Process ◽  
Cost Benefit Analysis ◽  
Cost Benefit ◽  
Cost Effective ◽  
Benefit Analysis ◽  
Moving Bed ◽  
Trickling Filters ◽  
Sludge Hydrolysis ◽  
Effective Integration

On the basis of a cost-benefit analysis it was decided to expand the Arnsberg WWTP by a multistage biological process which allows for cost-effective integration of the existing facilities. Carbon removal will then be accomplished in a high-loaded activated sludge stage for which the existing primary clarifier is to be reconstructed. The existing trickling filters will be used for nitrification during a midterm period and will be replaced later on either by a moving bed system or by new trickling filters. Line 3 of the existing secondary clarifiers will be reconstructed and used for post denitrification in a moving bed system. The carbon needed for denitrification will be provided by means of sludge hydrolysis and the use of an external carbon source.

Recreational Prescription Drug Use Among College Students

NASPA Journal ◽  
2006 ◽  
Vol 43 (1) ◽  
Author(s):  
Ethan A Kolek
Keyword(s):  
Drug Use ◽  
Prescription Drug ◽  
Undergraduate Students ◽  
Prescription Drugs ◽  
Drug Users ◽  
Research University ◽  
Future Research ◽  
Negative Consequences ◽  
Prescription Drug Use ◽  
Other Substances

The purpose of this study was to explore recreational prescription drug use among undergraduate students. Although anecdotal accounts on this subject abound, empirical research is extremely limited. Data from a survey of a random sample of 734 students at a large public research university in the Northeast were examined. Results indicate that a substantial proportion of students reported having used prescription drugs for recreational purposes in the year prior to survey administration. Recreational prescription drug use was positively associated with the use of other substances including alcohol. Recreational prescription drug users were also more likely than other drug users to report negative consequences as a result of their drug use. Implications for future research and for student affairs are discussed.

Motivating Compliance: Firm Response to Mandatory Disclosure Policies

2018 ◽  
Vol 32 (2) ◽  
pp. 103-119
Author(s):  
Colleen M. Boland ◽  
Chris E. Hogan ◽  
Marilyn F. Johnson
Keyword(s):  
Conflict Of Interest ◽  
Low Cost ◽  
Cost Effective ◽  
Data Availability ◽  
Policy Adoption ◽  
Future Research ◽  
Regulated Firms ◽  
Firm Response ◽  
Disclosure Rules ◽  
The Impact

SYNOPSIS Mandatory existence disclosure rules require an organization to disclose a policy's existence, but not its content. We examine policy adoption frequencies in the year immediately after the IRS required mandatory existence disclosure by nonprofits of various governance policies. We also examine adoption frequencies in the year of the subsequent change from mandatory existence disclosure to a disclose-and-explain regime that required supplemental disclosures about the content and implementation of conflict of interest policies. Our results suggest that in areas where there is unclear regulatory authority, mandatory existence disclosure is an effective and low cost regulatory device for encouraging the adoption of policies desired by regulators, provided those policies are cost-effective for regulated firms to implement. In addition, we find that disclose-and-explain regulatory regimes provide stronger incentives for policy adoption than do mandatory existence disclosure regimes and also discourage “check the box” behavior. Future research should examine the impact of mandatory existence disclosure rules in the year that the regulation is implemented. Data Availability: Data are available from sources cited in the text.

The Future of Plasma-Based Surface Engineering Techniques in Tribology (Keynote)

2005 ◽  
Author(s):  
Allan Matthews ◽  
Adrian Leyland
Keyword(s):  
Surface Engineering ◽  
Performance Enhancement ◽  
Bulk Material ◽  
Cost Savings ◽  
Cost Effective ◽  
Ceramic Coatings ◽  
Performance Improvements ◽  
Treatment Techniques ◽  
Wide Range ◽  
Macro Scale

Over the past twenty years or so, there have been major steps forward both in the understanding of tribological mechanisms and in the development of new coating and treatment techniques to better “engineer” surfaces to achieve reductions in wear and friction. Particularly in the coatings tribology field, improved techniques and theories which enable us to study and understand the mechanisms occurring at the “nano”, “micro” and “macro” scale have allowed considerable progress to be made in (for example) understanding contact mechanisms and the influence of “third bodies” [1–5]. Over the same period, we have seen the emergence of the discipline which we now call “Surface Engineering”, by which, ideally, a bulk material (the ‘substrate’) and a coating are combined in a way that provides a cost-effective performance enhancement of which neither would be capable without the presence of the other. It is probably fair to say that the emergence and recognition of Surface Engineering as a field in its own right has been driven largely by the availability of “plasma”-based coating and treatment processes, which can provide surface properties which were previously unachievable. In particular, plasma-assisted (PA) physical vapour deposition (PVD) techniques, allowing wear-resistant ceramic thin films such as titanium nitride (TiN) to be deposited on a wide range of industrial tooling, gave a step-change in industrial productivity and manufactured product quality, and caught the attention of engineers due to the remarkable cost savings and performance improvements obtained. Subsequently, so-called 2nd- and 3rd-generation ceramic coatings (with multilayered or nanocomposite structures) have recently been developed [6–9], to further extend tool performance — the objective typically being to increase coating hardness further, or extend hardness capabilities to higher temperatures.

scholarly journals Environmental Engineering Techniques to Restore Degraded Posidonia oceanica Meadows

Water ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 661
Author(s):  
Luigi Piazzi ◽  
Stefano Acunto ◽  
Francesca Frau ◽  
Fabrizio Atzori ◽  
Maria Francesca Cinti ◽  
...  
Keyword(s):  
Large Scale ◽  
Natural Habitat ◽  
Cost Benefit ◽  
Cost Effective ◽  
Posidonia Oceanica ◽  
Environmental Engineering ◽  
Bottom Surface ◽  
Sessile Invertebrates ◽  
Set Up ◽  
Short Time

Seagrass planting techniques have shown to be an effective tool for restoring degraded meadows and ecosystem function. In the Mediterranean Sea, most restoration efforts have been addressed to the endemic seagrass Posidonia oceanica, but cost-benefit analyses have shown unpromising results. This study aimed at evaluating the effectiveness of environmental engineering techniques generally employed in terrestrial systems to restore the P. oceanica meadows: two different restoration efforts were considered, either exploring non-degradable mats or, for the first time, degradable mats. Both of them provided encouraging results, as the loss of transplanting plots was null or very low and the survival of cuttings stabilized to about 50%. Data collected are to be considered positive as the survived cuttings are enough to allow the future spread of the patches. The utilized techniques provided a cost-effective restoration tool likely affordable for large-scale projects, as the methods allowed to set up a wide bottom surface to restore in a relatively short time without any particular expensive device. Moreover, the mats, comparing with other anchoring methods, enhanced the colonization of other organisms such as macroalgae and sessile invertebrates, contributing to generate a natural habitat.

scholarly journals Performance of Iron-Functionalized Activated Carbon Catalysts (Fe/AC-f) on CWPO Wastewater Treatment

Catalysts ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 337
Author(s):  
Sara Mesa Medina ◽  
Ana Rey ◽  
Carlos Durán-Valle ◽  
Ana Bahamonde ◽  
Marisol Faraldos
Keyword(s):  
Wastewater Treatment ◽  
Activated Carbon ◽  
Landfill Leachate ◽  
Surface Composition ◽  
Treatment Plant ◽  
Reaction Medium ◽  
Pollutant Removal ◽  
Operating Conditions ◽  
Water Matrix ◽  
The Stability

Two commercial activated carbon were functionalized with nitric acid, sulfuric acid, and ethylenediamine to induce the modification of their surface functional groups and facilitate the stability of corresponding AC-supported iron catalysts (Fe/AC-f). Synthetized Fe/AC-f catalysts were characterized to determine bulk and surface composition (elemental analysis, emission spectroscopy, XPS), textural (N2 isotherms), and structural characteristics (XRD). All the Fe/AC-f catalysts were evaluated in the degradation of phenol in ultrapure water matrix by catalytic wet peroxide oxidation (CWPO). Complete pollutant removal at short reaction times (30–60 min) and high TOC reduction (XTOC = 80 % at ≤ 120 min) were always achieved at the conditions tested (500 mg·L−1 catalyst loading, 100 mg·L−1 phenol concentration, stoichiometric H2O2 dose, pH 3, 50 °C and 200 rpm), improving the results found with bare activated carbon supports. The lability of the interactions of iron with functionalized carbon support jeopardizes the stability of some catalysts. This fact could be associated to modifications of the induced surface chemistry after functionalization as a consequence of the iron immobilization procedure. The reusability was demonstrated by four consecutive CWPO cycles where the activity decreased from 1st to 3rd, to become recovered in the 4th run. Fe/AC-f catalysts were applied to treat two real water matrices: the effluent of a wastewater treatment plant with a membrane biological reactor (WWTP-MBR) and a landfill leachate, opening the opportunity to extend the use of these Fe/AC-f catalysts for complex wastewater matrices remediation. The degradation of phenol spiked WWTP-MBR effluent by CWPO using Fe/AC-f catalysts revealed pH of the reaction medium as a critical parameter to obtain complete elimination of the pollutant, only reached at pH 3. On the contrary, significant TOC removal, naturally found in complex landfill leachate, was obtained at natural pH 9 and half stoichiometric H2O2 dose. This highlights the importance of the water matrix in the optimization of the CWPO operating conditions.

Sign in / Sign up

Export Citation Format

Share Document