Uncoupling chemical looping gasification (CLG), the organic sulfur evolution was simulated and explored qualitatively and quantitatively using typical sulfur compounds on TG-MS and temperature-programmed fixed bed. The HS radical in the reductive atmosphere easier converted to H₂S and COS. H₂O activated the evolution of S which was stably bonded to carbon, and H₂ generated from gasification and oxidation of reductive Fe by H₂O contributed to the release of sulfur. The proportion of H₂S released from sulfur compounds was greater than 87% in steam gasification, and more than 60% during CLG. Oxygen carriers promoted the conversion of sulfur to SO₂ in the mid-temperature region (500 °C–700 °C), and H₂S in the high temperature region (700 °C–900 °C). Sulfur species played a pivotal role in sulfur evolution at low temperature of CLG. The organic sulfur in mercaptan and benzyl were more easily converted and escaped than in thiophene and phenyl. The thermal stability of sulfur species, the presence of steam and OC affected the initial temperature and peak concentration of gas sulfur release as well as sulfur distribution. Consequently, CLG strengthened the sulfur evolution, and made it possible to targeted restructure the distribution of sulfur by regulating process parameters, or blending fuel with different sulfur species for emission reduction, and selective conversion of sulfur.

Black carbon (BC), as one of the short-lived climate pollutants, is becoming more prominent contribution from non-road mobile source, especially for agricultural machinery (AM) in China. However, the understanding of BC emissions from AM is still not clear, and the BC emission factors (EFs) are also limited. In this study, we conducted real-world measurements on twenty AM to investigate the instantaneous BC emission characteristics and quantify BC EFs under the whole tillage processes. We find the instantaneous BC emissions and fuel consumptions are obvious differences and present good synchronization under different tillage processes. Multi-type (CO₂-, fuel-, distance-, time-, and area-based) EFs of BC are developed, which are significantly affected by different tillage processes and emission standards of the used AM. While AM conducting rotary tillage, ploughing, harvest corn and harvest wheat on the same area of land, total BC emissions by using the China III emission standard AM will be reduced by 56%, 36%, 88%, and 87% than those by using China II emission standard AM, respectively. Furthermore, for corn and wheat production under the whole tillage processes, BC EFs are 16.90 (6.03–39.12) g/hm² and 18.18 (5.91–38.69) g/hm², CO₂ EFs are 112.64 (72.07–195.98) g/hm² and 103.72 (71.47–167.02) g/hm², respectively. We estimate the BC and CO₂ emissions from wheat and corn productions based on the average area-based EFs. The large fluctuation ranges of BC and CO₂ emissions in different tillage processes and the whole processes can reflect that the use of AM in China is uneven. It also indicates that there is a large space for BC and CO₂ emission reduction and optimization. Therefore, more attention should be paid to the control of BC and CO₂ emissions from AM. We believe that the recommended multi-type EFs are applicable for the quantification of BC emissions from AM in China and other countries.

Cardiovascular diseases (CVD) are leading global health issue. More studies have linked indoor air pollution from solid fuel usage to hypertension risk, a leading risk factor for CVD. We conducted a systematic review and meta-analysis of observational studies assessing the relationship of indoor air pollution from solid fuel with hypertension risk. Using a protocol standardized a priori, two independent reviewers searched PubMed, the Cochrane Library, Ovid MEDLINE, Web of Science and EMBASE for available studies published before Dec.1, 2019. A random effects model was used to analyse the pooled results. Out of 3740 articles, 47 were reviewed in depth and 11 contributing to this meta-analysis. The use of household solid fuel was significantly associated with an increased risk of hypertension (OR = 1.52, 95% CI = 1.26 to 1.85). The smoking-controlled group (OR = 2.38, 95% CI = 1.58 to 3.60) had greater effect size of hypertension than the uncontrolled group (OR = 1.11, 95% CI = 1.10 to 1.11). These findings implicate that indoor air pollution from solid fuel may be an important risk factor for hypertension.

An understanding of the dispersion and level of emissions source of atmospheric pollutants; whether point, area or volume sources, is required to inform policies on air pollution and day-to-day predictions of pollution level. Very few studies have carried out simulations of the dispersion pattern and ground-level concentration of pollutants emitted from real-world gas flares. The limited availability of official data on gas flares from the oil and gas industries makes accurate dispersion calculations difficult. Using ADMS 5 and AERMOD, this study assessed the sensitivity of dispersion and ground-level concentration of pollutants from gas flares in the Niger Delta to prevailing meteorological condition; fuel composition; and flare size. Although, during the non-WAM (West African Monsoon) months (November and March), the simulated ground-level concentrations of pollutants from a single flare are lower, the dispersion of pollutants is towards both the inland and coastal communities. In the WAM months, the ground-level concentrations are higher and are dispersed predominantly over the inland communities. Less buoyant plumes from smaller flares (lower volume flow rates) and/or flaring of fuel with lower heat content results in higher ground-level concentrations in areas closer to the flare. Considering the huge number of flares scattered around the region, a mitigation of the acute local pollution level would be to combine short stacks flaring at lower volume flow rates to enhance the volume flow rate of a single exhaust, and hence, the buoyancy of the plume exiting the stack.

One of the most important reasons for the controversy over the development of nuclear energy is the proper disposal of spent fuel. Separation of actinide and lanthanide ions is an important part of safe long-term storage of radioactive waste. Herein, a three-dimensional (3D) graphene-based macrostructure (GOCS) was utilized to remove actinide thorium and lanthanide europium ions from aqueous solutions. The adsorption of Eu(III) and Th(IV) on the GOCS was evaluated as a function of adsorption time, solution pH, initial ion concentrations, and ionic strength. The experimentally determined maximum adsorption capacities of this GOCS for Eu(III) (pH 6.0) and Th(IV) (pH 3.0) are as high as 150 and 220 mg/g, respectively. By using Fourier transformation infrared (FT-IR), X-ray photoelectron (XPS), and extended X-ray absorption fine structure (EXAFS) spectroscopy, we concluded that the Eu(III) and Th(IV) adsorption was predominantly attributed to the inner-sphere coordination with various oxygen- and nitrogen-containing functional groups on GOCS surfaces. Our selective adsorption results demonstrate that the actinide and lanthanide ions can be effectively separated from transition metal ions. This study provides new clues to the overall recycling of actinide and lanthanide ions in radioactive environmental pollution treatments.

Seven organophosphorus compounds (OPs) were measured in urban fine and coarse particulate matter (PM) collected from two sites of Nanjing (XCNUC), China and Islamabad (APHSP), Pakistan. The fine PM mass at APHSP site was significantly higher (p = 0.005) in the spring (mean 22.5 μg/m³) than in the summer (mean 12.7 μg/m³). The total concentration, ∑⁷OPs, of samples collected at APHSP was found significantly higher in coarse (range 672–47621 pg/m³) than in fine PM (range 1200–15213 pg/m³); while ∑⁷OPs from XCNUC in fine (range 1696–15063 pg/m³) and coarse PM (range 2053–5379 pg/m³) were statistically different in samples during summer, based on two-sample t-test at 0.05 confidence interval. Seasonally, ∑⁷OPs was found to be higher in the samples of Nanjing (9510 ± 3633 pg/m³) in the summer than in the spring. In contrast, the samples of Islamabad had higher ∑⁷OPs (25558 ± 16255 pg/m³) in the spring than in the summer. Tri(chloropropyl) phosphate (TCEP) was found at higher concentration than any other OPs in the samples from the XCNUC site. Triphenyl phosphate (TPhP) was found at extremely high levels from APHSP, which may attributed to its use in jet fuel. Most of the ∑OPs concentrations were found significantly different in both PMs at both sites due to their diverse sources. Both sites showed strong correlation of ∑OPs with TCEP in both PMs, indicating similar mode of transfer from sources like plastics, lacquer, paint, glue, industrial processes and foam fillers. Relative abundance of OPs in fine and coarse PM differs amongst OP congeners and concerning seasons, with these variations attributed to different mechanisms of mass transfer such as volatilization, condensation and abrasions. Moreover, triphenylphosphine oxide (TPPO) has been reported in outdoor PMs. This is the first study on the occurrence of OPs in atmospheric fine and coarse PM and their seasonal variation from Pakistan and China.

Indoor air pollution is an important environmental factor that contributes to the burden of various diseases. Long-term exposure to ambient air pollution is associated with telomere shortening. However, the association between chronic indoor air pollution from household fuel combustion and leukocyte telomere length has not been studied. In our study, 137 cancer-free non-smokers were recruited. Their exposure levels to indoor air pollution from 1985 to 2014 were assessed using a face-to-face interview questionnaire, and leukocyte telomere length (LTL) was measured using a monochrome multiplex quantitative PCR method. Accumulative exposure to solid fuel usage for cooking was negatively correlated with LTL. The LTL of residents who were exposed to solid fuel combustion for three decades (LTL = 0.70 ± 0.17) was significantly shorter than that of other populations. In addition, education and occupation were related to both exposure to solid fuel and LTL. Sociodemographic factors may play a mediating role in the correlation between leukocyte telomere length and environmental exposure to indoor air pollution. In conclusion, long-term exposure to indoor air pollution may cause LTL dysfunction.

This study investigated and compared wintertime air pollution and personal exposure in the rural northern and southern Chinese homes. Daily indoor and outdoor particle samples were simultaneously collected by using stationary samplers, and personal exposure was directly measured using portable carried samplers. The daily average concentrations of indoor and outdoor PM2.5 were 521 ± 234 and 365 ± 185 μg/m³ in the northern village, that were about 2.3–2.7 times of 188 ± 104 and 150 ± 29 μg/m³ in indoor and outdoor air in the southern villages. Particle size distribution was similar between indoor and outdoor air, and had relatively smaller difference between the two sites, relative to the particle mass concentration difference. PM2.5 contributed to ∼80% of the TSP mass, and in PM2.5, near 90% were PM1.0. In homes using electricity in the southern villages, outdoor air pollution could explain 70–80% of the variation in indoor air pollution. The daily exposure to PM2.5 measured using personal carried samplers were 451 ± 301 μg/m³ in the northern villages with traditional solid fuels used for daily cooking and heating, and in the southern villages without heating, the exposure to PM2.5 were 184 ± 83 and 166 ± 45 μg/m³, respectively, for the population using wood and electricity for daily cooking. Time-weighted daily average exposure estimated from area concentration and time spent indoor and outdoor was generally correlated the directly measured exposure.