This work investigates the feasibility of co-mechanochemical treatment of oil-contaminated drill cuttings (OCDC), circulation fluidized bed combustion (CFBC) fly ash, and quicklime to prepare non-sintered lightweight aggregates (NSLWAs). The NSLWAs with high cylinder compressive strength and low water absorption could be obtained under the condition of optimal water addition and appropriate steam-curing temperature, as well as steam-curing time. Co-mechanochemical treatment could enhance the pozzolanic reactivity of CFBC fly ash effectively, which is beneficial to the strength development of NSLWAs. Moreover, co-mechanochemical treatment also can degrade the petroleum hydrocarbon of OCDC, greatly reducing the leaching concentrations of total petroleum hydrocarbons (TPH) of NSLWAs. The final leaching concentrations of TPH are much lower than the requirements of Chinese National Standard GB 31571–2015. Graphical abstract

Heavy metal pollution is a global ecological safety issue, especially in crops, where it directly threatens regional ecological security and human health. Selecting scientific evaluation methods is an important prerequisite for understanding the distribution of heavy metals in a region. To evaluate the distribution characteristics of arsenic (As), cadmium (Cd), copper (Cu), and zinc (Zn) in farmland soil–rice system in Doumen District of Zhuhai City, Pearl River Delta, we analyzed the high geological background area and heavy metal contents in soil by inverse distance–weighted interpolation and single-factor pollution index. Bioconcentration factor (BCF) was used to study the migration and accumulation characteristics of heavy metals. Then, the soil–rice system was evaluated comprehensively with a novel evaluation method, i.e., the influence index of comprehensive quality (IICQ). Results showed that As, Cd, Cu, and Zn in the soil of the study area followed normal distribution. Cd and Cu were the main pollutants whose point contamination rates were 50% and 22.86%, respectively. A total of 2.86% of the soil were contaminated by As, and no Zn contamination was observed in the soil. At the same time, As and Cd in rice were partially polluted, and the Cu and Zn were not polluted. The order of bioaccumulation coefficient was Cd > Zn > Cu > As, and no evident enrichment was observed. According to the impact index of IICQ to evaluate the pollution of heavy metals in the soil–rice system, 96.98% of the soil in study area was in a state of moderate, heavy, and extreme pollution, which were concentrated in the northern and central parts of the study area. The soil–rice system in the high geological background area was in a subhealthy state. A total of 90.69% of the soil were polluted, but the rice met the national food safety standards.

The Fluid Catalytic Cracking Unit process converts heavy vacuum gas oil into more valuable products in the presence of zeolite catalyst at 520 °C and 2.5 bar. The coke is burned off with air in the regenerator tower at 700 °C and 230 ton / h of flue gases are produced. The flue gases consist of CO₂ (12.7% mole), N₂ (66.2% mole), H₂O (19.2% mole), O₂ (1.7% mole), and SO₂ (0.2% mole). In this study, the chemical absorption of CO₂ in an absorption and desorption pilot plant was investigated and this process was simulated by Aspen Hysys. The pilot plant used has an absorber tower of 15 cm in diameter and a stripper tower of 10 cm. The towers were filled up to 1.5 m with 3-mm Raschig ring packing. A concentration of 30 wt% diethanolamine (DEA) solvent is used for CO₂ absorption. Absorption was carried out at 1.1 bar, solvent temperature of 40 °C, flue gas temperature of 60 °C, and liquid to gas ratio (L/G = 3.7). Amine regeneration was carried out at 125 °C and 1.9 bar. The CO₂ absorption efficiency in the pilot plant was obtained 96% and in Aspen Hysys simulation its 95%. The CO₂ recovery efficiency in the stripper tower obtained 95% and CO₂ purity is 94.6%. The overall efficiency of the chemical absorption with this process is 92%, and the regeneration energy in the stripper tower is 2.52 GJ/ton-co₂. With this method, 1003 ton/day CO₂ is captured from the FCCU flue gases and preventing emission to the atmosphere.

The increasing attention to agricultural exports and sustainability issues is driving a surge of interest in the life cycle assessment (LCAs) of greenhouse crop production in Albania. Meanwhile, most of the reported agricultural LCAs tend to be generic without considering regionalized environmental sensitivities. In this study, ReCiPe 2016, covering 18 midpoint indicators and 3 endpoint indicators was used to generate a full-fledged cradle-to-farm gate LCA of greenhouse tomatoes in a typical Albanian farm including spatial differentiation and indicators not covered by contemporary LCAs. The most important midpoint categories per 1 ha identified from foreground–background analysis were global warming (2660.4 kg CO₂-eq), stratospheric ozone depletion (0.0308 kg CFC11-eq), particulate matter formation (7.99 kg PM2.5-eq), human health and ecosystem ozone formation (8.47 and 14.95 kg NOₓ-eq), water consumption (2293.23 m³), and terrestrial acidification (42.28 kg SO₂-eq). The application of spatial differentiation resulted in higher impacts with about 21% for particulate matter formation, 12% for human health ozone formation, 134% for ecosystem ozone formation, 19% for terrestrial acidification, and 13% for water consumption. The impacts primarily originated from nitrogen-based fertilizer emissions and diesel fuel with the origin of the impact from nitrous oxide (N₂O), ammonia volatilization (NH₃), nitrogen oxides (NOx), and non-methane volatile organic compounds (NMVOCs). Water consumption was dominated by irrigation water use. Overall, at the endpoint level, 9% and 24% less cumulative damage to human health and ecosystem quality were calculated with respect to the site-generic analysis primarily from the cause-and-effect chain of water consumption (mainly lower water stress index). This affirms the importance of regional considerations in LCA calculations to reflect the impacts accordingly (i.e., the magnitude of impacts, the most relevant midpoint categories, and their relevance on endpoint level) and increase the possibility of making correct conclusions and sub-optimizations, i.e., increase the discriminating power of LCA.

In this study, nano-sized cellulose modified with lactic acid (MW-Ce-LA) was prepared with the assistant of microwave then used for the adsorption of Cu²⁺ from real samples. This modified cellulose was characterized by means of FTIR, TEM, XRD, and elemental analysis. ICP-OES was used for determination of Cu²⁺. The effect of pH, adsorption times, temperature, sorbent dose, and initial adsorbate concentration were studied to detect the ideal adsorption condition. Langmuir model proved to be the best to fit the adsorption isotherm experiments with maximum adsorption capacity of 90.3 mg g⁻¹ Cu²⁺. Calculated thermodynamic parameters (ΔG° and ΔH°) for adsorption of Cu²⁺ on MW-Ce-LA suggested exothermic and nonspontaneous character of the adsorption process. The reusability tests indicated regeneration of the prepared adsorbent simply using 1 mol L⁻¹ of HCl. The examined method was used effectively to preconcentrate Cu²⁺ from water, blood, and food samples.

Balancing economic growth, resource conservation, and atmospheric environmental protection has topped the agenda of academics and policy makers. The article takes the panel data of 37 Chinese industrial sectors from 2003 to 2016 as the research object to explore the impact of atmospheric environmental regulation on industrial total factor productivity and the possible path of capital intensity. Furthermore, to analyze the possible industry heterogeneity of the above results, the article classifies the industrial sectors into heavy polluting industries and light polluting industries, based on their air pollution emission intensity. The key discoveries of this study are as follows: (1) Generally, the regulation of atmospheric environment has a significant inhibitory effect on industrial total factor productivity. However, if measured by industry group, atmospheric environmental regulation has a significant inhibitory effect on industrial total factor productivity in the light polluted industry group, while in the heavy polluted industry group, the impact is less significant. (2) Across all the industries and especially the light polluted industry group, the capital intensity is a partial intermediate variable of the influence of atmospheric environmental regulation on industrial total factor productivity, but the mediating effect is not significant in the heavy polluted industry group. Finally, policy suggestions are given from the following three aspects: promoting accurate industrial governance, selecting environmental regulation methods and improving supporting policies, which provide practical and feasible solutions for improving the current atmospheric environment governance and promoting the improvement of industrial total factor productivity.

The China-Pakistan Economic Corridor (CPEC) is a journey towards economic integration of Eurasia. The CPEC contains US$62 billion investment projects on energy, infrastructure, and other development projects in Pakistan. However, CPEC could enhance climate change vulnerabilities for the faltering economy of Pakistan due to its three possible environmental risks and repercussions. Its major environmental concern is related to energy projects as three quarters of the newly planned energy will be generated from traditional coal-fired power plants. Traditional coal power plants are the major contributors to CO₂ emissions and smog, which ultimately lead to global warming and climate change. Its second important environmental concern is linked with massive tree cutting for the construction of various road networks from Kashghar, China, to Gwadar, Pakistan. Tree cutting leads to enormous concentration of CO₂ emissions along the road networks. Vehicle trafficking is its third important environmental threat. Karakorum highway is expected to carry up to 7000 trucks per day that will release up to 36.5 million tons of CO₂. Despite all the environmental risks, the CPEC enables Pakistan to manage energy crisis and upgrade aging infrastructure. However, if appropriate remedial measures are not taken to diminish environmental risks, Pakistan will be among major contributors to CO₂ emissions, and its rank will be worsen in global climate risk index, after completion of this project. Therefore, it is very crucial to assess possible environmental impacts of CPEC projects regarding energy, infrastructure, and transportation. Furthermore, scientists from both countries should collaborate to manage the environmental repercussions of CPEC projects.

In this study, it was found that the CeVO₄-CeO₂ nanocomposite possessed remarkably selective catalytic reduction (SCR) performance and wider active temperature scope. And, the promotion principle was explored based on BET, XRD, XPS, H₂-temperature-programmed reduction, NH₃-temperature-programmed desorption, and in situ diffuse reflectance infrared Fourier transform (DRIFT) techniques. The characterization outcomes manifested that the CeVO₄-CeO₂ nanocomposite could inhibit its crystallinity and enhance the concentrations of chemisorbed oxygen species and Ce³⁺, which was advantageous to the SCR process. Moreover, the in situ DRIFT technique manifested that the NH₃-SCR reaction over Ce₀.₇₅V₀.₂₅Oy was enhanced effectively through the mechanism of L-H.

Global warming regarded as the major global issue over the past few decades, whereas carbon dioxide (CO₂) emissions have been cited as one of the main causes of this problem. Therefore, this study aims to investigate the effect of energy consumption, economic development, and population growth on high CO₂ emitting sectors of Pakistan such as transportation, industrial, and household. The data used in this study was taken from multiple databases from 2000 to 2018. We employed novel grey relational analysis (GRA) models to assess the connection between gross domestic product (GDP) per capita, population, energy consumption, and CO₂ emission. Furthermore, the Hurwicz method was used to analyze which factor contributing more to CO₂ emission. Result reveals that CO₂ emission, gross domestic product per capita, population, and energy consumption showed a strong association among all sectors. Whereas, population contributes more to intensifying CO₂ emissions in the transportation sector of Pakistan. This study provides useful insights for policymakers to take preventive and corrective measures to overcome CO₂ emissions as well as sustainable development.