Chemical Waste Management Research Articles

Prediction of Flash Point of Materials Using Bayesian Kernel Machine Regression Based on Gaussian Processes With LASSO‐Like Spike‐and‐Slab Hyperprior

ABSTRACTThe determination of flash points is a critical aspect of chemical safety, essential for assessing explosion hazards and fire risks associated with flammable solutions. With the advent of new chemical blends and the increasing complexity of chemical waste management, the need for accurate and reliable flash point prediction methods has become more pronounced. This study introduces a novel predictive approach using Bayesian kernel machine regression (BKMR) with Gaussian process priors, designed to meet the growing demand for precise flash point estimation in the context of chemical safety. The BKMR model, underpinned by Bayesian statistics, offers a comprehensive framework that not only quantifies prediction uncertainty but also enhances interpretability amidst experimental data variability. Our comparative analysis reveals that BKMR surpasses traditional predictive models, including support vector machines, kernel ridge regression, and Gaussian process regression, in terms of accuracy and reliability across multiple metrics. By elucidating the intricate interactions between molecular features and flash point properties, the BKMR model provides profound insights into the chemical dynamics that influence flash point determinations. This study signifies a methodological leap in flash point prediction, offering a valuable tool for chemical safety analysis and contributing to the development of safer chemical handling and storage practices.

Science Laboratory Learning Environment and Students’ Practices on Laboratory Safety

This paper aims to identify the significant relationship between the science laboratory learning environment and students’ practices on laboratory safety for education students who took at least one subject or course with laboratory unit in face-to-face classes. The data from this study came from 201 education students, collected through an online survey using Google Forms. The non-experimental descriptive correlational design, census approach was used to select the study participants, and standardised questionnaires were also utilised. The weighted mean, standard deviation, Pearson product-moment correlation design, and linear regression analysis were employed as statistical techniques. The study found that the science laboratory learning environment is at a very high level. Meanwhile, the students’ practices on laboratory safety, especially emergency response plans, work procedures, and chemical waste management, are at a very high level, while safety equipment and handling of experiments are observed at a high level. The results also showed a significant relationship between the science laboratory learning environment and students’ practices on laboratory safety. The domain of science laboratory learning environment that significantly predicts students’ practices is the material environment. The result implied that the institution may provide and maintain a conducive laboratory learning environment, which is essential for students to perform laboratory safety, enhance the handling of experiments, and upgrade the safety equipment in the science laboratory.

Risk assessment and green chemistry applied to waste generated in university laboratories

Chemical reagents have become fundamental products in daily life use, they contribute in several ways to establish a high level of social development. In the case of higher education, the use of reagents allows learning thought laboratory practices. These practices must be carried out under preventative measures, in order to avoid negative impacts on the environment and human health; this generates the need to identify and classify the chemical substances used and the waste generated. This research was developed at the Faculty of Environmental Engineering at Universidad Santo Tomás in the Villavicencio campus, the objective was to apply the concepts of Green Chemistry in the laboratory guidelines, in addition to guaranteeing the proper management of the chemical waste generated. Initially, the hazard of twenty-one (21) laboratory guides based on the Globally Harmonized System (GHS) ninth revised edition (2021) was determined. Subsequently, an update was performed by applying Green Chemistry to ten (10) of the laboratory guides that represented the greatest hazards, and finally, a manual was established for the management of chemical waste resulting from laboratory practices. The results determined that in the subject of Inorganic Chemistry the guidelines Physical and Chemical Properties of the Matter presents the highest hazard index, due to lead nitrate, which was evaluated as the most hazard reagent, because of its carcinogenicity (1B) and reproductive toxicity (1A). The proposed update to the guidelines was possible by replacing the chemical substances used in order to reduce by 24% the risk associated with them and the by 50% the use of reagents in relation to the same laboratory guidelines defined in the first stage.

BOAS PRÁTICAS SUSTENTÁVEIS DE GESTÃO DE RESÍDUOS QUÍMICOS EM INSTITUIÇÕES PÚBLICAS DE ENSINO SUPERIOR

THE BEST SUSTAINABLE PRACTICES FOR CHEMICAL WASTE MANAGEMENT IN PUBLIC HIGHER EDUCATION INSTITUTIONS. This work proposes the minimum items for the composition of the best sustainable practices for chemical waste management in higher education institutions (HEI). It was made a bibliographical and documentary review of the Brazilian legislation applicable to the management of chemical waste, with the aim of supporting the elaboration of the best sustainable practices for chemical waste management and propose to assist the technical managers of HEI in the implementation of sustainable and safe management of chemical waste.

The Analysis of Chemical Waste Management System in Integrated Waste Management Site of Lampung University

The waste management system of the Integrated Waste Management Site of the Lampung University is considered quite effective in handling the university organic waste, besides that the university also gets commercial benefits. This study analyzes the chemical waste management system at the Integrated Waste Management Site of the Lampung University and its potential in reducing university chemical waste independently. The type of research carried out was using descriptive research and use a qualitative approach by conducting observational studies and in-depth interviews. Waste management activities at the Integrated Waste Management Site of the Lampung University include waste collection, sorting and waste processing activities. One of the programs in the waste management process at the Integrated Waste Management Site of the Lampung University is known as the Unila Waste Bank.

Hyaluronic Acid Allows Enzyme Immobilization for Applications in Biomedicine.

Enzymes are proteins that control the efficiency and effectiveness of biological reactions and systems, as well as of engineered biomimetic processes. This review highlights current applications of a diverse range of enzymes for biofuel production, plastics, and chemical waste management, as well as for detergent, textile, and food production and preservation industries respectively. Challenges regarding the transposition of enzymes from their natural purpose and environment into synthetic practice are discussed. For example, temperature and pH-induced enzyme fragilities, short shelf life, low-cost efficiency, poor user-controllability, and subsequently insufficient catalytic activity were shown to decrease pertinence and profitability in large-scale production considerations. Enzyme immobilization was shown to improve and expand upon enzyme usage within a profit and impact-oriented commercial world and through enzyme-material and interfaces integration. With particular focus on the growing biomedical market, examples of enzyme immobilization within or onto hyaluronic acid (HA)-based complexes are discussed as a definable way to improve upon and/or make possible the next generation of medical undertakings. As a polysaccharide formed in every living organism, HA has proven beneficial in biomedicine for its high biocompatibility and controllable biodegradability, viscoelasticity, and hydrophilicity. Complexes developed with this molecule have been utilized to selectively deliver drugs to a desired location and at a desired rate, improve the efficiency of tissue regeneration, and serve as a viable platform for biologically accepted sensors. In similar realms of enzyme immobilization, HA’s ease in crosslinking allows the molecule to user-controllably enhance the design of a given platform in terms of both chemical and physical characteristics to thus best support successful and sustained enzyme usage. Such examples do not only demonstrate the potential of enzyme-based applications but further, emphasize future market trends and accountability.

Continuous improvement of chemical waste management to enhance safety in laboratory waste room

Continuous improvement of chemical waste management to enhance safety in laboratory waste room

CHEMICAL WASTE MANAGEMENT IN EDUCATIONAL INSTITUTIONS

Green universities and Education for Sustainable Development have an important role in reaching a sustainable society. However, there is many gaps in this area. This study aimed to report the implementation and the results of the Chemical Waste Management Program (CWMP) of the Federal University of Lavras (UFLA). The CWMP have been implemented in 2009 to solve the existing environmental problem of inadequate disposal of chemical waste generated in UFLA’s laboratories. In order to carry out the CWMP actions, the Chemical Waste Management Laboratory (CWML) was created in 2009, with the function of collecting, treating, and giving a final destination to the chemical waste generated by UFLA’s teaching, research, and service laboratories. The treatments applied to chemical waste are adsorption, precipitation, distillation, drying and composting. Another important action of the CWMP was the realization of training courses and seminars, in addition to a graduate discipline, to raise awareness of the academic community about the importance of the correct disposal of chemical waste. The development of sustainable treatment methods, using recycled and low-cost materials allowed an increase of 400% in the amount of waste treated in the CWML. From 2009 to 2019, the CWML increased the number of solvents recovered from the waste and the amount of Chemical Waste Exchange (CWE). The CWMP contributed for UFLA to apply the concept of green chemistry daily. The results from these actions have contributed for the university to reach the second position among most sustainable universities in Latin America. Despite the increase in the amount of treated waste, it is necessary to develop new sustainable treatment methodologies to meet the university's growing demand.

Development of environmental education concepts concerning chemical waste management and treatment: the training experience of undergraduate students

It is essential to develop a safety culture with the participation of university teachers and students in actions and studies that can contribute to safer and more sustainable practices in academic laboratories. The present work analyzes the potential of a training program to raise awareness and establish environmental education and green chemistry concepts concerning procedures for the management and treatment of chemical waste generated in experimental classes. This is a qualitative case study providing a critical perspective of environmental education. The training activity, lasting 45 minutes, was conducted with 66 students entering Chemistry courses at a Brazilian public university. Data collection was carried out using an initial questionnaire to identify the students’ prior knowledge, and a final one applied after the training period. The questionnaires contained open questions and closed questions with a Likert-type scale. The results showed that the training activity contributed to the students’ understanding of the concepts, procedures, and attitudes related to the management and treatment of chemical waste, including the interrelations among the environmental, social, and economic impacts of waste management, the importance of correct separation and storage of residues for disposal using different types of treatment, the civil liability of the academic community for the residues generated, and how the 3Rs principles can favor sustainable practices in the academic context.

Chemical Waste Management in Hospital; Impact on Environment and Health

This article discusses the chemical management of wastewater in hospitals. Liquid waste is all wastewater including feces originating from hospital activities which may contain pathogenic microorganisms, toxic chemicals and radioactive substances that are harmful to health. Therefore, the potential impact of hospital wastewater on public health is very large, so each hospital is required to treat its wastewater until it meets the applicable standard requirements. Good wastewater management is not only for sharp medical wastes but covers hospital waste as a whole. With the increasing number of health service facilities, it will result in an increasing potential for environmental pollution, because waste disposal activities, especially waste water, will contribute to decreasing the level of human health. Hospital waste is all waste generated from hospital activities in the form of solid, liquid and gas. It is better if hospital waste has a waste storage and treats the waste first before discharging it into the environment, so that the environment is not polluted and the government should build a monitoring system.

Self-Organized Single-Atom Tungsten Supported on the N-Doped Carbon Matrix for Durable Oxygen Reduction.

Rational engineering of atomically scaled metal-nitrogen-carbon (M-N-C) moieties has been the topic of recent research interest because of their potential application as an electrochemical oxygen reduction reaction (ORR) catalyst. Despite numerous efforts on M-N-Cs, attaining both adequate activity and a satisfactory stability simultaneously is a principal issue. Herein, we demonstrated the synthesis of a single-atom tungsten catalyst supported on the N-doped carbon matrix (W-N-C) and its application as an ORR catalyst. W-N-C was synthesized using the economically viable, simple, one-step pyrolysis of dicyandiamide and tungsten(VI) chloride at moderate temperature (700 °C). The synthesis of W-N-C avoids any post acid treatment as it does not require any subsidiary sacrificial metal like Zn and, hence, does not induce any burden associated with chemical waste management. The atomic dispersion of W atoms stabilized by N-doped porous carbon and the formation of WN2C2 were confirmed by high-angle annular dark-field scanning transmission electron microscopy and X-ray absorption spectroscopy. Interestingly, as-synthesized WN2C2 exhibited unprecedented electrocatalytic activity with a half-wave potential of 764 mV vs reversible hydrogen electrode (RHE) as well as significantly enhanced stability (retaining >99% diffusion-limited current density and the loss in activity is 10.5% at 0.84 V after 10,000 potential cycles), which is much better than the stability limit set by the US Department of Energy in an alkaline medium. Overall, the activity of W-N-C surpasses that of Pt/C after 5000 cycles. The excellent stability is believed to be due to the symmetric coordination of the metal active site (W2N2C2).

Power to liquid through waste as a carbon source: A technical and economic assessment

The combination of a power to methanol process with the use of waste for carbon supply turns out to be a cleaver solution for sustainable chemical production and waste management as well as long-term energy storage. In the current work, an innovative scheme which integrates waste and energy conversion to produce methanol is addressed. Within the proposed configuration syngas is produced from waste gasification and enriched with hydrogen produced through water electrolysis, in order to accomplish methanol synthesis requirements. A techno-economic and environmental analysis of the hybrid scheme is proposed together with its comparison with waste to methanol and direct power to methanol technologies. Direct waste conversion into methanol is today the most attractive solution. In a near future, however, considering the increase of the renewable share of power and reduction of power cost, the hybrid scheme may become a quite attractive solution.

Minimizing laboratory waste and improving material reuse through chemical waste exchange: Case of a Brazilian institution.

Concern over the management of chemical wastes from laboratories has been gaining importance since the 1990s. For a good management of chemical wastes generated from laboratories, it is recommended that managers encourage an environment of cooperation and exchange, thus reusing chemical reagents. The institution under study implemented the Chemical Waste Exchange, whose objective is to capture reagents past their expiry dates that would be discarded and make them available internally to other areas or even to other institutions. A total of 1075 reagents were reused internally and 4382 items were donated for external institutions. As for financial data, between 2011 and 2018, the internal economy was US$16,700.70 and for external institutions it was US$62,633.11. When comparing the waste reuse according to the destination, an internal address showed a significant difference when compared with the external use. Some categories of reagents have greater added value and provide even greater benefits when reused. The strategy of capturing and making available expired reagents through the Chemical Waste Exchange is positive; it helps the management of the waste generated; the economic benefit will depend on the market value of the material; the adopted strategy avoids the need to remove raw material from nature for the production of new reagents and reduces the costs related to treatment and environmentally appropriate final destination.

Práticas ambientais em laboratórios químicos universitários: uma revisão sistemática de literatura

Esta pesquisa tem como objetivo identificar práticas ambientais implementadas em laboratórios químicos universitários visando a sua disseminação. Para tanto, o método utilizado compreendeu uma revisão sistemática de literatura usando três bases de dados: Scopus, Web of Science e Scielo. No total, 35 artigos foram selecionados com base em critérios de inclusão de uma amostragem inicial de 2.514. A análise dos artigos selecionados permitiu a identificação de 46 práticas ambientais implementadas em laboratórios químicos universitários. Essas práticas foram categorizadas de acordo com o aspecto ambiental ou conforme relacionado a gestão e controle ambiental, a saber: gerenciamento de resíduos, gerenciamento de produtos químicos, educação ambiental, eficiência energética, conservação da água, gestão e planejamento, design da infraestrutura e conformidades legais. Por fim, essa revisão sistemática amplia a literatura ao abordar diferentes práticas ambientais além do gerenciamento de resíduos químicos, como por exemplo o gerenciamento de produtos químicos, a educação ambiental e as relacionadas à gestão e planejamento.

Use of carbon dioxide as raw material to close the carbon cycle for the German chemical and polymer industries

This article explores how far the use of CO2 as raw material could enable the German chemical and polymer industries to contribute to a circular economy. Material Flow Analysis was conducted for all carbon flows for material use in Germany, comprising chemical production, polymer production, domestic use and waste management. For scenario modelling, Carbon Capture and Utilization technologies were included, and key parameters determining carbon flows were altered to show potential corridors for the future development. The results show that current carbon flows are dominated by fossil sources and are highly linear, with a secondary input rate of only 6%. Additionally, 12% (2 Mt/a) of the primary carbon input is lost due to dissipation. Currently available Carbon Capture and Utilization technologies would allow reaching a secondary input rate of 65% for the chemical industry. However, to achieve this rate between 80% (processes of direct synthesis) and 103% (methanol-based processes) of the total net supply for renewable electricity in Germany would be required in 2030 and between 41% and 50% in 2050. In contrast, the unavoidable substance related CO2-point sources in Germany could probably fulfill the carbon requirement for material use of the chemical industry in 2050. The authors conclude that the utilization of CO2 as a carbon source is necessary to close the carbon cycle where material or chemical recycling is technically not feasible or reasonable. The very high demand for renewable electricity indicates that the required production facilities for CO2-based chemicals will probably not be completely based in Germany.

Analysis of the Evolution of Hazardous Chemical Waste from Medicolegal Activities

The paper presents an analysis of the management of hazardous chemical waste from medicolegal. activities. The analysis is based on eight years survey of the hazardous chemical waste management, ponting out the current procedures. The time series analysis is used to predict the evolution of such medical waste, and according to the forecast some strategic objective for reducing the amount of chemical waste are proposed.

Conceptualizing sustainable diets in Vietnam: Minimum metrics and potential leverage points

A major barrier to achieving sustainable diets is the lack of clearly defined and agreed upon intervention points that will positively influence multiple sectors of the food system. There is an urgent need to understand what policy approaches and interventions will most effectively enhance the sustainability of diets in rapidly urbanizing low- and middle-income countries. To address this need, this work combines the input of diverse stakeholders and analysis of existing datasets to develop a conceptual framework for sustainable diets that is locally relevant to Vietnam using a process that is generalizable to other developing countries. The resulting framework includes 235 unique, measurable indicators within eight domains: (1) food production, (2) food processing and distribution, (3) food loss and waste, (4) food access and consumption, (5) food and water safety, (6) nutrition, (7) sociopolitical context, and (8) environmental impact. This conceptual framework was employed in a participatory workshop that brought together 50 Vietnamese stakeholders from diverse areas of expertise to identify and prioritize specific metrics for measuring sustainable diets. Based on the results of the stakeholder workshop, expert interviews, and characterized datasets, a comprehensive set of minimum metrics for each domain was produced and key leverage points that are likely to have an impact across multiple sectors were identified. These leverage points include food quality and safety, agricultural chemical usage, food waste, and water management. The analysis is expected to contribute to evidence-based policymaking in Vietnam to cultivate more sustainable diets.

Chemical waste management is still in a very poor state in much of Asia

China is one of the largest producers, consumers, and emitters of cadmium (Cd). This study applies the methods of material flow analysis and inventory analysis to investigate the flows and stocks of Cd in the industry-environment system in mainland China from 1990 to 2015. Special attention is paid to the identification of emissions and corresponding sources. It was found that: (1) more than 63% of Cd input in mainland China comprised unintentional processes that were driven by domestic mining and refining of nonferrous ores, which exceeded the input driven by intentional processes; (2) China became a net importer of Cd in 2000 because of the increasing import of nonferrous ores, which then led to Cd accumulation in domestic solid wastes; (3) Cd resources were mainly consumed in Ni–Cd batteries and plastics, and the in-use stock of Ni–Cd batteries reached a peak in 2008; (4) Cd emissions started to rise in 1990 and remained steady after 2013 due to the relatively stable production of nonferrous ores. The tendency of Cd emissions, use of Cd resources, and development of Cd-relevant industries were also discussed. The results indicated that the utilization of traditional products and the production of new energy materials may become the most important application of Cd resources in China.

A terrible waste: Chemical waste management is still in a very poor state in much of Asia

A terrible waste: Chemical waste management is still in a very poor state in much of Asia

Greening the Curriculum: A Strategic Waste Management for Chemical Wastes in School Laboratories

Despite global awareness on the effects of improper chemical waste disposal, the actual practice of proper waste handling is still neglected. Serving as the best venue for information dissemination, schools can reinforce waste management programs through its curriculum. Identification of curriculum areas that can complement waste management strategies by evaluating the level of awareness and participation of its teaching employees, non-teaching staff, and students is the main objective of this study. Validated self-constructed survey-questionnaires were administered to 149 respondents representing the total population of the laboratory teachers, students, non-teaching employees, and researchers of the Western Institute of Technology, Philippines whose primary job deals with chemicals. The data gathered and analyzed using student t-test showed that there is no significant difference in the level of awareness among teaching and non-teaching employees in terms of the school's chemical waste management program. A significant number of senior high school students showed lack of awareness on Philippine environmental laws and the chemical waste management in school. Employees whose primary job is not associated with teaching and research do not realize their role in chemical waste minimization. More senior high school students show environmental concern over college students, but it is the latter group that apply the concepts of chemical waste management into actual practice.