Production of light olefins and monocyclic aromatic hydrocarbons from the pyrolysis of waste plastic straws over high-silica zeolite-based catalysts.

Owing to the ever-increasing generation of plastic waste, the need to develop environmentally friendly disposal methods has increased. This study explored the potential of waste plastic straw to generate valuable light olefins and monocyclic aromatic hydrocarbons (MAHs) via catalytic pyrolysis using high-silica zeolite-based catalysts. HZSM-5 (SiO2/Al2O3:200) exhibited superior performance, yielding more light olefins (49.8 wt%) and a higher MAH content than Hbeta (300). This was attributed to the increased acidity and proper shape selectivity. HZSM-5 displayed better coking resistance (0.7 wt%) than Hbeta (4.4 wt%) by impeding secondary reactions, limiting coke precursor formation. The use of HZSM-5 (80) resulted in higher MAHs and lower light olefins than HZSM-5 (200) because of its higher acidity. Incorporation of Co into HZSM-5 (200) marginally lowered light olefin yield (to 44.0 wt%) while notably enhancing MAH production and boosting propene selectivity within the olefin composition. These observations are attributed to the well-balanced coexistence of Lewis and Brønsted acid sites, which stimulated the carbonium ion mechanism and induced H-transfer, cyclization, Diels-alder, and dehydrogenation reactions. The catalytic pyrolysis of plastic straw over high-silica and metal-loaded HZSM-5 catalysts has been suggested as an efficient and sustainable method for transforming plastic waste materials into valuable light olefins and MAHs.

Recent advances in liquid fuel production from plastic waste via pyrolysis: Emphasis on polyolefins and polystyrene.

The management of plastic waste (PW) has become an indispensable worldwide issue because of the enhanced accumulation and environmental impacts of these waste materials. Thermo-catalytic pyrolysis has been proposed as an emerging technology for the valorization of PW into value-added liquid fuels. This review provides a comprehensive investigation of the latest advances in thermo-catalytic pyrolysis of PW for liquid fuel generation, by emphasizing polyethylene, polypropylene, and polystyrene. To this end, the current strategies of PW management are summarized. The various parameters affecting the thermal pyrolysis of PW (e.g., temperature, residence time, heating rate, pyrolysis medium, and plastic type) are discussed, highlighting their significant influence on feed reactivity, product yield, and carbon number distribution of the pyrolysis process. Optimizing these parameters in the pyrolysis process can ensure highly efficient energy recovery from PW. In comparison with non-catalytic PW pyrolysis, catalytic pyrolysis of PW is considered by discussing mechanisms, reaction pathways, and the performance of various catalysts. It is established that the introduction of either acid or base catalysts shifts PW pyrolysis from the conventional free radical mechanism towards the carbonium ion mechanism, altering its kinetics and pathways. This review also provides an overview of PW pyrolysis practicality for scaling up by describing techno-economic challenges and opportunities, environmental considerations, and presenting future outlooks in this field. Overall, via investigation of the recent research findings, this paper offers valuable insights into the potential of thermo-catalytic pyrolysis as an emerging strategy for PW management and the production of liquid fuels, while also highlighting avenues for further exploration and development.

Towards health with justice: making the tobacco industry accountable through administrative liability.

For many decades, the transnational tobacco industry has evaded the consequences of harming people and the planet. Despite selling a deadly product, it has continued to remain one of the most profitable industries in the world, now venturing into 'wellness and pharmaceutical' businesses as part of its diversification strategy. Meanwhile, efforts to make the tobacco industry pay through court systems have not progressed due to the inherent challenges within the judicial systems in most countries. This paper explores mechanisms for ensuring accountability through administrative liability, including the use of compensation mechanisms and adjudicatory bodies. Such mechanisms operationalise vital principles and practices derived from international law, such as the imposition of effective, proportionate, and dissuasive non-criminal sanctions, victims' right to compensation, and 'polluter pays' principles. Measures such as taxation, surcharges, penalties, financial guarantees or insurance, along with the establishment of adjudicatory bodies and trust funds, are discussed. In order to hold the tobacco industry to account for the wide range of harms caused by its products and its misconduct; policies on 'liability' must clearly articulate how the industry will compensate for past and future harms in a manner that deters it from causing further damage.

Prevention and control of non-communicable diseases in iran: the case for Investment.

BACKGROUND: Non-communicable diseases are imposing a considerable burden on Iran. This study aims to assess the Return on Investment (ROI) for implementation of Non-communicable diseases (NCDs) prevention program in Iran. METHODS: Four disease groups including cardiovascular diseases, diabetes, cancer, and respiratory diseases were included in our ROI analysis. The study followed four steps: 1) Estimating the total economic burden of NCDs using the Cost-of-Illness approach. 2) Estimating the total costs of implementing clinical and preventive interventions using an ingredient based costing at delivering level and a program costing method at central level.3) Calculating health impacts and economic benefits of interventions using the impact measures of avoided incidence, avoided mortality, healthy life years (HLYs) gained, and avoided direct treatment costs. 4) Calculating the ROI for each intervention in 5- and 15- year time horizons. RESULTS: The total economic burden of NCDs to the Iranian economy was IRR 838.49 trillion per year (2018), which was equivalent to 5% of the country's annual Gross Domestic Product (GDP). The package of NCD will lead to 549 000 deaths averted and 2 370 000 healthy life years gained over 15 years, and, financially, Iranian economy will gain IRR 542.22 trillion over 15 years. The highest ROI was observed for the package of physical activity interventions, followed by the interventions addressing salt, tobacco package and clinical interventions. Conclusions NCDs in Iran are causing a surge in health care costs and are contributing to reduced productivity. Those actions to prevent NCDs in Iran, as well as yielding to a notable health impact, are giving a good economic return to the society. This study underscores an essential need for establishment of a national multi-sectorial NCD coordination mechanism to bring together and strengthen existing cross-agency initiatives on NCDs.

Risk control of heavy metal in waste incinerator ash by available solidification scenarios in cement production based on waste flow analysis.

Incineration is a common method in municipal solid waste management, which has several advantages such as reducing the volume of waste, but with concerns about exhaust gas and ash management. In this study, heavy metals in bottom ash, secondary furnace ash and fly ash of two waste incinerators in Tehran and Nowshahr were analyzed and its control in cement production was investigated. For this purpose, twelve monthly samples of three types of incinerator ash were analyzed. By combining the studied ashes in the raw materials, the quantity of metals in the cement was analyzed. Finally, by investigating four scenarios based on quantitative variations in the routes of municipal solid waste, ash quantity and the related risk caused by its heavy metals were studied. The results showed that the concentration of heavy metals in the three ash samples of the studied incinerators was 19,513-23,972 µg/g and the composition of the metals included Hg (less than 0.01%), Pb (2.93%), Cd (0.59%), Cu (21.51%), Zn (58.7%), As (less than 0.01%), Cr (15.88%), and Ni (0.91%). The best quality of produced cement included 20% ash and 10% zeolite, which was the basis of the next calculations. It was estimated that the reduction of the release of metals into the environment includes 37 gr/day in best scenario equal to 10.6 tons/year. Ash solidification can be considered as a complementary solution in waste incinerator management.

Production of biodiesel via esterification of coffee waste-derived bio-oil using sulfonated catalysts.

Catalytic esterification of acid-rich coffee waste-derived bio-oil was performed using sulfonated metal oxide catalysts (Al2O3, MgO, ZrO2, and TiO2) and ethanol to produce fatty acid alkyl esters. The potential of the sulfonated catalysts for esterification decreased in the following order: Ti-SO4 > Zr-SO4 > Al-SO4 > Mg-SO4. Particularly, Ti-SO4 and Zr-SO4 resulted in 91.2 % (peak area %) and 85.2 % esters, respectively. This is attributed to the contributions of well-dispersed Brønsted acid sites created by -SO3H functional groups, additional Lewis acid sites formed by Ti and Zr oxides, and their appropriate pore size. Compared with HCl and H3PO4, the use of H2SO4 for TiO2 treatment significantly enhanced ester formation. When using Ti-SO4, increasing the catalyst-to-feedstock ratio (1/2 âˆ¼ 1/10) significantly increased the esters' selectivity (38.7 %∼94.7 %). Ethanol utilization caused a superior selectivity for esters than methanol, while the increasing temperature favored ester production. This study proposes an eco-friendly and practical method for biodiesel generation.

Improved biohydrogen production using Ni/ZrxCeyO2 loaded on foam reactor through steam gasification of sewage sludge.

The pervasive generation of sewage sludge (SES) and deficiencies in its disposal methods have resulted in several significant environmental and human health challenges. This study explored the catalytic effect of nickel (Ni)-based CeO2, ZrO2, Zr0.8Ce0.2O2, Zr0.4Ce0.6O2, and γ-Al2O3 supports in fixed beds and foam reactors in the steam gasification of SES. A comparison of the hydrogen selectivity and gas yield of the synthesized catalysts confirmed that the metal composite support, especially Zr0.8Ce0.2O2, had a positive effect on the catalytic activity and stability. This can be attributed to the enhanced oxygen vacancies and oxygen mobility, resistance to coke deposition, uniform morphology, improved dispersion, and increased number of Ni sites on the Zr0.8Ce0.2O2 support. Furthermore, foam reactors offer unique advantages in improving hydrogen production. This study provides an advanced strategy for SES valorization that fulfills the requirements of an economically and environmentally sustainable technology.

Enhanced mono-aromatics production by the CH4-assisted pyrolysis of microalgae using Zn-based HZSM-5 catalysts.

This study presents the catalytic pyrolysis of microalgae, Chlorella vulgaris (C. vulgaris), using pure CH4 and H2-rich gas evolved from CH4 decomposition on three different HZSM-5 catalysts loaded with Zn, Ga, and Pt, aimed specifically at producing high-value mono-aromatics such as benzene, toluene, ethylbenzene, and xylene (BTEX). In comparison with that for the typical inert N2 environment, a pure CH4 environment increased the bio-oil yield from 32.4 wt% to 37.4 wt% probably due to hydrogen and methyl radical insertion in the bio-oil components. Furthermore, the addition of bimetals further increased bio-oil yield. For example, ZnPtHZ led to a bio-oil yield of 47.7 wt% in pure CH4. ZnGaHZ resulted in the maximum BTEX yield (6.68 wt%), which could be explained by CH4 activation, co-aromatization, and hydrodeoxygenation. The BTEX yield could be further increased to 7.62 wt% when pyrolysis was conducted in H2-rich gas evolved from CH4 decomposition over ZnGaHZ, as rates of aromatization and hydrodeoxygenation were relatively high under this condition. This study experimentally validated that the combination of ZnGaHZ and CH4 decomposition synergistically increases BTEX production using C. vulgaris.

Fractional condensation of bio-oil vapors from pyrolysis of various sawdust wastes in a bench-scale bubbling fluidized bed reactor.

The use of lignocellulosic waste as an energy source for substituting fossil fuels has attracted lots of attention, and pyrolysis has been established as an effective technology for this purpose. However, the utilization of bio-oil derived from non-catalytic pyrolysis faces certain constraints, making it impractical for direct application in advanced sectors. This study has focused on overcoming these challenges by employing fractional condensation of pyrolytic vapors at distinct temperatures. The potential of five types of sawdust for producing high-quality bio-oil through pyrolysis conducted with a bench-scale bubbling fluidized bed reactor was investigated for the first time. The highest yield of bio-oil (61.94 wt%) was produced using sample 3 (damaged timber). Remarkably, phenolic compounds were majorly gathered in the 1st and 2nd condensers at temperatures of 200 °C and 150 °C, respectively, attributing to their higher boiling points. Whereas, carboxylic acid, ketones, and furans were mainly collected in the 3rd (-5 °C) and 4th (-20 °C) condensers, having high water content in the range of 35.33%-65.09%. The separation of acidic nature compounds such as acetic acid in the 3rd and 4th was evidenced by its low pH in the range of 4-5, while the pH of liquid collected in the 1st and 2nd condensers exhibited higher pH (6-7). The well-separated bio-oil derived from biomass pyrolysis facilitates its wide usage in various applications, proposing a unique approach toward carbon neutrality. In particular, achieving efficient separation of phenolic compounds in bio-oil is important, as these compounds can undergo further upgrading to generate hydrocarbons and diesel fuel.

Evaluation of the Effects of PAKDAM, an Invented Device to Get Nitrous Oxide and Oxygen, in the Consumers: A Report of Pilot Study.

Background: Since last decade, a device called PAKDAM (means clean inspiration) was invented in Iran which has been used in some cafe to prepare N2O and O2 as a new instrument instead of using water pipe. This study aimed to evaluate the respiratory and health effects of Pakdam and investigate its short and midterm side effects in users. Materials and Methods: In a case-control pilot study between September 2021 and March 2022, 152 individuals were divided into two groups: 76 consumers (case) and 76 non- consumers (control). Both groups were divided into two groups of 36 smokers and 36 non-smokers. Participants signed the participation form and filled out the demographic data questionnaire, and then their vital signs, O2 saturation, expiratory CO, and spirometry tests were recorded. Results: The subjects who used the device had a mean blood pressure of 123.71±16.11 mmHg, oxygen saturation of 97.2±1.9, exhaled carbon monoxide of 9.8±5.5, and an FVC / FEV1 ratio of 88.5±7.9. These figures in control group were (137.79±18.15) - (94.1±4.2) - (14.3 ± 9.3) and (83.9 ± 10.4), respectively. In addition to the effects on the respiratory system, consumers had lower heart rates and lower systolic and diastolic blood pressures. Conclusion: The blood oxygen level and FEV1/FVC ratio were higher in subjects using Pakdam and the amount of exhaled carbon monoxide and blood pressure were lower. This condition was more common in smokers and less in non-smokers. It is possible to see the favorable effects of using Pakdam device on people especially in smokers.

Evaluation of smoking status: comparison of self-reports with exhaled carbon monoxide analysis in university students in the Islamic Republic of Iran.

BACKGROUND: Smoking is considered the leading risk factor for many chronic diseases and deaths worldwide. Thus, it is important to determine the number of smokers before implementing tobacco control initiatives. Due to stigma and deterrent measures, it is impossible to access smokers through a self-report questionnaire. AIMS: To compare exhaled carbon monoxide levels with self-reports among university students in the Islamic Republic of Iran. METHODS: This cross-sectional study included a convenience sample of 60 university students recruited in 2016 in Tehran. There were 30 women and 30 men with an average age of 23.1 (±15.6) years. They were interviewed using an adaptation of the International Union Against Tuberculosis and Lung Diseases questionnaire and further assessed by breath analysis. Smoking status was compared and then correlated with the resultant carbon monoxide levels at a cutoff of 6 ppm. RESULTS: Mean cigarette consumption was 4.7 (±1.8) each day and smoking status was reported as 19 (31.7%) current smokers and 41 (68.3%) nonsmokers of tobacco. Significant correlations were obtained between the exhaled carbon monoxide levels of the smoker and nonsmoker groups (P < 0.05). Irrespective of the measures of smoking status, the frequency of detecting smokers was comparable to that of detecting nonsmokers (P = 0.756). CONCLUSIONS: Similar to self-reports, the exhaled carbon monoxide measurement successfully distinguished smokers from nonsmokers. This allows healthcare providers and policy-makers to examine the effectiveness of tobacco cessation and prevention programmes.

Greenhouse Gases Life Cycle Assessment (GHGLCA) as a decision support tool for municipal solid waste management in Iran.

BACKGROUND: One of the most problems in developing countries is the integrated waste management and the effects on Greenhouse Gases (GHG) emission, Life Cycle Assessment (LCA) is used in this paper as a decision supporting tool in planning Municipal Solid Waste (MSW) managements. METHODS: In this paper the EPA's Waste Reduction Model (WARM) that provide GHG emission factors for waste stream components that are based on life Cycle Inventory (LCI) framework were used and The MSW management methods comprised in seven scenarios. RESULTS: The amount of GHG which was generated from Iran's waste sector estimated about 17836079 Metric Tons of Carbon dioxide Equivalents (MT CO2e) in this study. The lowest amount of GHG was generated by LFG capture system with energy recovery (557635 MT CO2e), while Incineration of materials being sent to landfill (1756823 MT CO2e), Landfill Gas (LFG) capture system with flaring (2929150 MT CO2e) and Improved source reduction and recycling (4780278 MT CO2e) emitted fewer GHG than the other scenarios. Lowest levels of gross energy consumption occur in source reduction with recycling and composting (-89356240 Mega British Thermal Unit, M BTU), recycling and composting (-86772060 M BTU) as well as Improved source reduction with recycling and composting (-54794888 M BTU). CONCLUSIONS: It appears that recycling and composting each offer significant GHG emissions and energy consumption reductions (scenarios 4, 5 and 6). Upon of the GHG emission and energy consumption results concluded that improved source reduction and recycling scenario has been the Balanced and appropriate technology for handling the solid waste streams in municipalities.

Age-at-death estimation based on the macroscopic examination of spheno-occipital sutures.

OBJECTIVE: To examine the closure degree of spheno-occipital synchondrosis and its relationship with chronological age. MATERIALS AND METHODS: Cross-sectional analysis of the closure degree of spheno-occipital suture was done through direct inspection of 376 autopsies from both sexes whose ages ranged between 8 and 26 years in Legal Medicine Organization of Tehran, Iran from 1st of July 2007 to 1st of July 2009. The correlation between the degree of closure and chronological age was investigated. RESULTS: Mean ages of open, semi-closed and closed sutures were 12.27, 16.12 and 21.17 years in males, and 9.04, 12.38 and 19.44 in females, respectively. Seemingly, their difference was significant (p < 0.001). Partial fusion (semi-closed) was seen at the age of 12 in both sexes while complete fusion (closed) was seen at 15 year olds or above in males and 12 year olds or above in females. Spearman's correlation ratio coefficient showed a linear correlation between age and suture situation in both sexes (rho = 0.788, P < 0.001 in males and r = 0.645, P < 0.001 in females). CONCLUSION: The study showed that the closure degree of spheno-occipital suture can be used as a good indicator for age estimation in both sexes. Cadavers can be correctly grouped above or below 16 years old with sensitivity of 79.82% and specificity of 89.47% in males and above or below 13 years old with sensitivity of 100.00% and specificity of 81.58% in females.

Alteration in male reproductive system in experimental cholestasis: roles for opioids and nitric oxide overproduction.

Cirrhosis is associated with impairment of the male reproductive system, hypogonadism and feminization. It is important to rule out whether the impairment in the reproductive system exists earlier in the course of cholestatic liver disease to target effective therapies at the best time point. In this study we investigated the role of endogenous opioid and nitric oxide system in alterations of the reproductive system in male rats. We performed sham or bile duct ligation surgery on male Sprague-Dawley rats and treated the animals for seven days with saline, naltrexone, an opioid receptor blocker (20 mg/kg) and N (G)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor (10 mg/kg). We then evaluated the plasma level of testosterone, luteinizing hormone (LH) and follicle stimulating hormone (FSH), sperm count and motility as well as biomarkers of cholestasis and nitric oxide productions. The results showed that following cholestasis, total testosterone level decrease and LH level increase in plasma of cholestatic rats and treatment with L-NAME and naltrexone could improve the plasma level of testosterone. Naltrexone could decrease the elevated level of LH in cholestatic animals. In addition, the weight of seminal vesicles and prostate significantly decreased in cholestasis as compared to the control group and treatment with L-NAME and naltrexone could improve the weights of the two organs in cholestasis. Our results demonstrate for the first time that the male reproductive system is impaired early in cholestasis and that endogenous opioid and nitric oxide system contribute to these impairments in the early course of the disease.