Atmospheric-pressure and continuous-flow synthesis of 1,3-diphenylurea from CO2 and aniline over CeO2 catalyst assisted by 2-cyanopyridine and its life cycle perspective on pathways toward lower CO2 emissions

ABSTRACTThere is concern about the hazard of acute residential CO exposures from portable gasoline-powered generators, which can result in death or serious adverse health effects in exposed individuals. To address this hazard, the U.S. Consumer Product Safety Commission has developed low CO emission prototype generators by adapting off-the-shelf emission control technologies onto commercially available generators. A series of tests was conducted to characterize the indoor CO concentrations resulting from portable generators operating in the attached garage of a research house under seven different test house/garage configurations. The tested generators include both unmodified and modified low CO emission prototypes. It was found that CO concentrations varied widely, with peak house CO concentrations ranging from under 10 ppm to over 10,000 ppm. The highest concentrations in the house resulted from operation of the unmodified generator in the garage with the garage bay door closed and the house access door open. The lowest concentrations resulted from operation of a modified low CO emission prototype in the garage with the garage bay door open and the house access door closed. These tests documented reductions of up to 98% in CO concentrations due to emissions from two low CO emission portable generators compared to a stock generator.Implications: Improper portable generator use has caused 800 U.S. deaths in the past 14 years. Generators operated in attached garages can cause CO to quickly reach deadly levels. Two low-emission prototypes generators were tested and had CO emissions reduced by up to 98%. Low-emission generators can reduce the risk of consumer poisonings and deaths.

It is essential to study CO2 emissions intensity as the most critical factor affecting temperature increase and climate change in a country like Iran, which ranked seven regarding CO2 emissions intensity. Investigating the convergence of CO2 emissions intensity is essential in recognizing its dynamics in identifying the effectiveness of government environmental policies. In this paper, using the Markov chain and spatial Markov chain methods, the convergence of CO2 emissions intensity from fossil-fuel consumption has been investigated in 28 provinces of Iran from 2002 to 2016. The empirical results showed that convergence clubs and neighbors significantly influenced the transition probability of regions to clubs with high and low CO2 emissions. Therefore, if a province had a neighbor with low (high) CO2 emissions intensity, the transition probability of this province to the club with low (high) CO2 intensity increased. Therefore, in provinces that have neighbors with low (high) CO2 emissions intensity, the transition probability to the club with low (high) CO2 intensity increases.

Methane emissions along biomethane and biogas supply chains are underestimated

Individuals and institutions seeking to reduce travel-related carbon dioxide (CO2) emissions by changing travel modes need information on the amount of CO2 that can be saved by rail travel rather than air travel. This study uses flight emissions data from the International Civil Aviation Organization (ICAO) to estimate average per-passenger CO2 emissions saved by using rail travel between selected city pairs in the northeastern U.S. Trend lines are developed from the ICAO data for different aircraft types to facilitate comparison with CO2 emissions from rail travel. Separate rail emission factors are calculated for portions of Amtrak’s system operating electric and diesel locomotives. An adjustment factor is estimated to account for longer rail distances than flight distances. Results show rail travel has generally lower CO2 emissions than air travel, with substantially lower emissions for electrified segments of the Amtrak system. At flight distances of over 700 miles, air travel using single-aisle jets can have lower per-passenger CO2 emissions compared to diesel-powered rail travel, accounting for the longer distances by rail. Implications: Savings in per-passenger CO2 emissions using rail rather than air travel in the northeastern U.S. Travel by rail in the northeastern U.S. results in lower CO2 emissions compared to travel by air between the same city pairs using existing airline and passenger rail infrastructure. Savings are higher for cities connected by electrified rail.

Urban solid waste management is an important component of urban sustainability. The concept of evaluating technologies from both life cycle and urban metabolism perspectives is proposed in this study. The analysis from life cycle perspective (using physical input-output life cycle assessment model) provides support for determining the priority of technologies, and the analysis from urban metabolism perspective (using physical input-output model) provides support for identifying the acceptability of technologies. Suzhou City in China is taken as an example. From urban metabolism perspective, sludge recycling is regarded as an accepted method, while current fly ash recycling method is unsatisfying. Technical levels of scrap tire recycling and food waste recycling should be improved to reduce their negative effects on Suzhou's urban metabolism. From life cycle perspective, sludge recycling has the smallest environmental impacts, and scrap tire recycling has larger environmental impacts than food waste recycling does. Thus, more concerns should be paid to technical improvements of scrap tire recycling than to that of food waste recycling. The concept of evaluating technologies from both life cycle and urban metabolism perspectives in this study provides foundations for evaluating technologies in other countries and cities.

Author(s): Rapp, Vi H.; Cheng, Robert K.; Therkelsen, Peter L. | Abstract: Previous research has shown that on-demand water heaters are, on average, approximately 37% more efficient than storage water heaters. However, approximately 98% of water heaters in the U.S. use storage water heaters while the remaining 2% are on-demand. A major market barrier to deployment of on-demand water heaters is their high retail cost, which is due in part to their reliance on multi-stage burner banks that require complex electronic controls. This project aims to research and develop a cost-effective, efficient, ultra-low emission burner for next generation natural gas on-demand water heaters in residential and commercial buildings. To meet these requirements, researchers at the Lawrence Berkeley National Laboratory (LBNL) are adapting and testing the low-swirl burner (LSB) technology for commercially available on-demand water heaters. In this report, a low-swirl burner is researched, developed, and evaluated to meet targeted on-demand water heater performance metrics. Performance metrics for a new LSB design are identified by characterizing performance of current on-demand water heaters using published literature and technical specifications, and through experimental evaluations that measure fuel consumption and emissions output over a range of operating conditions. Next, target metrics and design criteria for the LSB are used to create six 3D printed prototypes for preliminary investigations. Prototype designs that proved the most promising were fabricated out of metal and tested further to evaluate the LSB’s full performance potential. After conducting a full performance evaluation on two designs, we found that one LSB design is capable of meeting or exceeding almost all the target performance metrics for on-demand water heaters. Specifically, this LSB demonstrated flame stability when operating from 4.07 kBTU/hr up to 204 kBTU/hr (50:1 turndown), compliance with SCAQMD Rule 1146.2 (14 ng/J or 20 ppm NOX @ 3% O2), and lower CO emissions than state-of-the art water heaters. Overall, the results from this research show that the LSB could provide a simple, low cost burner solution for significantly extending operating range of on-demand water heaters while providing low NOX and CO emissions.

Dazzled by diesel? The impact on carbon dioxide emissions of the shift to diesels in Europe through 2009

The object of research is the processes of substantiating strategic directions for energy efficiency on the basis of intelligent decarbonization and sustainable development based on cluster analysis, taking into account international experience and challenges of the global environment. The problem that has been addressed is the lack of a systematic approach to clustering countries by energy efficiency, which also takes into account indicators of intelligent decarbonization. This makes it difficult to develop targeted strategies to improve energy efficiency and decarbonization, especially given the specifics of AI and innovative technologies in different countries. The essence of the study results is to identify five clusters of the selected countries such as USA, India, Japan, China, Ukraine, Romania, Hungary, Poland, Czech Republic, Turkey, Portugal, Belgium, Greece, Sweden, Spain, Norway, Austria, Finland, Italy, France, The Netherlands, Germany, Switzerland, United Kingdom using cluster analysis based on the following indicators: Applied AI research score. Government Strategy AI: Strategy score. Commercial Ecosystem AI: Companies score. Energy intensity. Carbon dioxide emissions from energy. Cluster 1 includes India and Ukraine, countries with high energy intensity and significant CO₂ emissions, but with the potential to develop intelligent decarbonization. Cluster 2 is represented by the United States, a leader in AI and innovation, with low energy intensity but high CO₂ emissions due to its advanced industry. Cluster 3 covers countries with low energy intensity and low CO₂ emissions but weak AI development. Cluster 4 includes China, a country with a high level of AI research and commercial ecosystem, but high energy intensity and CO₂ emissions due to intensive industry. Cluster 5 covers countries with medium to high AI development, low to medium energy intensity, and varying levels of CO₂ emissions. The key principles of energy efficiency in these clusters are identified and strategic priorities for the development of energy efficiency in modern countries are defined. The results obtained can be used in practice to develop energy efficiency and decarbonization strategies at the national and international levels.

The energy consumption and CO2 emission of Swedish production of flat and long products of structural steel have been assessed by means of LCI data from the IISI study. Two general factors reduce the expenditure of energy and CO2 emission in Swedish production of both flat and long products: energy efficient steel processes; and extremely low CO2 emissions for generation of electricity. For flat steel products two specific features also contribute to their low energy consumption and CO2 emission: the use of magnetite iron ore instead of hematite; and a product programme with a uniquely large share of high strength steels. The latter allows significant weight savings in end products, thus resulting in global net reductions of energy consumption and CO2 emission. Even when transport of Swedish products to export markets are included, the Swedish figures are more favourable than those of steels manufactured domestically in their respective markets.

Graphene-based concrete: Synthesis strategies and reinforcement mechanisms in graphene-based cementitious composites (Part 1)

Ultrasound with water as a green solvent is an effective strategy for reducing losses and increasing the utilization of by-products. The extraction of proteins and specialized plant metabolites from sugar beet leaves (Beta vulgaris subsp. vulgaris var. altissima) promotes sustainability in the agro-food chain. Guided by sustainability, samples treated with ultrasound showed lower energy consumption and lower CO2 emissions. Furthermore, the spectrophotometric determination revealed higher protein and phenol yields in ultrasonically treated samples compared to thermally treated ones. The highest yield of total proteins, 147.91 ± 4.58 mg (gd.m.)−1, was observed during ultrasound treatment (amplitude 100%, treatment time 9 min). Under the same extraction conditions, the same trend was observed in the yield of total phenols 17.89 ± 0.38 mg (gd.m.)−1. High-power ultrasound, compared to the thermal extraction method, has increased the yield of proteins and specialized plant metabolites with significantly lower energy consumption and CO2 emissions. The obtained results are in accordance with the foundations of sustainable development. From an economic and environmental point of view, ultrasound with the use of green solvents would be an excellent replacement for conventional extraction methods.

Core Ideas The use of soil management at line (alone) reduces the CO2 emission. The higher soil aggregation favorece the higher CO2 emission. The soil management at line (alone) improve the lower soil desegregation. The objective was to determine the influence of partial cultivation of only the crop row on carbon dioxide (CO2) emissions in an Oxisol and Ultisol. The experimental design was a large paired‐plot design with treatments consisting of targeted chiseling to only the planting row to chiseling the whole field. Soil CO2 emissions, soil temperature, and soil moisture were measured daily for 12 d after tillage. In the Oxisol, CO2 emissions were higher on the second day after tillage and then decreased until Day 6. When analyzing the effect of tillage, chiseling in the planting row (CPR) showed, in general, lower CO2 emissions (2.54 µmol m−2 s−1) when compared to chiseling in total area (CTA) (3.32 µmol m−2 s−1), regardless of the day after tillage. However, the linear regression analysis between soil CO2 emissions and soil moisture in the Ultisol was significant for CPR (R2 = 0.79, p < 0.01) and CTA (R2 = 0.58, p < 0.01). Total soil CO2 emissions were higher in the Oxisol for both tillage systems (CPR = 1020.9 kg CO2 ha−1 and CTA = 1336.3 kg CO2 ha−1) than the Ultisol (CPR = 587.0 kg CO2 ha−1 and CTA = 649.3 kg CO2 ha−1). These results indicate that soil tillage by using CPR favors a lower soil CO2 emission to the atmosphere and contributes to a reduction in soil degradation when cultivated with sugarcane (Saccharum officinarum L.).

I. IntroductionGas to Liquids (GTL) is one of clean alternative fuels which loosely defined terms that is generally used to describe the chemical conversion of natural gas to some type of liquid products. As such, it excludes the production of liquefied natural gas (LNG), but includes the conversion of gas to methanol, liquid fuels, and petrochemicals, being the most common applications. In other words, Gas to liquids (GTL) technology is used to convert a carbon containing feedstock such as natural gas, to synthetic diesel fuels and further developed by oil companies. Fewer studies investigated the use of GTL diesel with the existing diesel engines to study the effect of using this new alternative fuel on the efficiency and emissions in these engines. Hence, the objectives of this study are to investigate the behavior of the GTL – diesel fuel blends in context of different combustion characteristics, engine performance and emissions. It is expected that the outcomes of this study will shed further light o...

Higher remediation efficiency of Cd and lower CO2 emissions in phytoremediation systems with biochar application.

Study of alkali activated slag as alternative pavement binder