Display omitted
•TiO2/G photocatalytic catalyst was prepared through a hydrothermal method.•TiO2/G catalyst was applied for the treatment of mineral processing wastewater.•18% TiO2/G showed superior ...photocatalytic performance than TiO2.
This study has invented a novel composite photocatalytic material of TiO2/graphene (TiO2/G) via the hydrothermal method. The prepared TiO2/graphene (TiO2/G) composite catalysts were investigated in detail using various characterisation experiments. The characterisation experiments indicated that the TiO2/graphene (TiO2/G) nanocomposites were successfully prepared. It can be observed that the TiO2 nanoparticles were observed uniformly distributing on the graphene oxide (GO) and the prepared TiO2/graphene (TiO2/G) nanocomposites possess huge specific surface area, small pore size, and low electron-hole pair complexation rate to degrade the pollutants. For the first time, TiO2/G is used as a photocatalytic material to treat mineral processing wastewater. Compared to GO and TiO2, under simulated light irradiation, the photodegradation efficiency of 18% TiO2/G samples reached 97.03% after 100 min. By successfully anchoring TiO2 on GO, the photoresponse range of TiO2/G was broadened (from 200–380 nm to 200–800 nm). The activity was also further improved (after 100 min of simulated light, the photocatalytic efficiency of pure TiO2 was only 17.88%, and the photocatalytic efficiency of 18% TiO2/G was 5.43 times higher than that of pure TiO2). This work advances the development of a potential photo-, photoelectro-systems for the treatment of real mineral processing wastewater.
The volumetric adsorption kinetics of carbon dioxide (CO
2
) onto the synthesized palm kernel shell activated carbon via single-stage CO
2
activation and commercial Norit® activated carbon were ...carried out at an initial pressure of approximately 1 bar at three different temperatures of 25, 50, and 100 °C. The experimental kinetics data were modelled by using the Lagergren’s pseudo-first-order model and pseudo-second-order model. Comparing these two, the non-linear pseudo-second-order kinetics model presented a better fit towards CO
2
adsorption for both adsorbents, owing to its closer coefficient of determination (
R
2
) to unity, irrespective of the adsorption temperature. In addition, kinetics analysis showed that the corresponding kinetics coefficient (rate of adsorption) of both activated carbons increased with respect to adsorption temperature, and thereby, it indicated higher mobility of CO
2
adsorbates at an elevated temperature. Nevertheless, CO
2
adsorption capacity of both activated carbons reduced at elevated temperatures, which signified exothermic and physical adsorption (physisorption) behaviour. Besides, process exothermicity of both carbonaceous adsorbents can be corroborated through activation energy (
E
a
) value, which was deduced from the Arrhenius plot.
E
a
values that were in range of 32–38 kJ/mol validated exothermic adsorption at low pressure and temperature range of 25–100 °C. To gain an insight into the CO
2
adsorption process, experimental data were fitted to intra-particle diffusion model and Boyd’s diffusion model, and findings revealed an involvement of both film diffusion and intra-particle diffusion during CO
2
adsorption process onto the synthesized activated carbon and commercial activated carbon.
The minimisation of the continuously enhancing level of the CO2 released to the atmosphere is one of the most significant issues faced by the scientific community. Rigorous research efforts have been ...carried out for the development of sustainable and cost-effective nitrogen-rich porous adsorbent materials for energy-efficient and enhanced polar gas separation, i.e. pre-combustion and post-combustion CO2 capture. Among different porous adsorbent materials, the covalent triazine frameworks (CTFs) are found to be remarkable candidates for CO2 capturing because of their facile and scalable synthesis, high surface area, permanent porosity, structural tunability, synthetic diversity, low density, high hydrothermal and physicochemical stability. A contextual overview is described on the key challenges in CO2 sequestration, parameters consideration for the design of CO2 selective porous adsorbents, evaluation criteria for the adsorption processes, assessment criteria for the selection of suitable adsorption configuration, and the factors influencing the CO2 adsorption capacity. This review comprises deep critical scrutiny of the current investigation and development on Triazine-, benzimidazole-, and triazole-based COPs with improved CO2 storage capacities. The conversion of CO2 into useful products including the carbon monoxide (CO), methane (CH4), methanol (CH3OH), and other products including the hydrocarbons has been critically reviewed by using the heterogeneous catalysis. Finally, a concise conclusion and recommendation section are presented indicating that the area of Triazine-, benzimidazole-, and triazole-based COPs for CO2 capture needs more attention to synthesise the next-generation materials for real-time applications.
Display omitted
•Global scenario on CO2 and GHGs emission are reported.•Adsorbent design parameters, evaluation and assessment criteria discussed.•Factors influencing the CO2 adsorption capacity are discussed.•Triazine-, benzimidazole-, and triazole-based COPs for CO2 adsorption reported.•Heterogenous Catalysts for CO2 conversion to useful products are critically reviewed.
The utilization of economic capabilities to raise production in the economy enhances the industrial activities and use of transportation. These activities deteriorate the quality of the environment ...and raise the level of particulate matter (PM
2.5
). The objective of this study is to investigate the impact of economic capabilities and population agglomeration on PM
2.5
emissions for the sample of 23 sub-Saharan African countries—a highly polluted region of the world. The study used panel regression from 2007 to 2015 and found that production capabilities are highly significant and directly effecting PM
2.5
emissions. The Kuznets hypothesis does not hold in this region, and the concentration of population in urban areas is also significant. To avoid the problem of possible endogeneity in the empirical model and for robustness check, the study also utilized system GMM and found consistent results. The findings of the study are highly valuable to reduce PM
2.5
and propose that the policymakers in Sub-Saharan African countries should opt for industrial specialization rather than economic complexity and ensure that the proper measures are taken to control PM
2.5
. Moreover, population concentrations should not be taken place in a few main urban cities.
Display omitted
•Hydrodynamic cavitation resulted in significant process intensification.•Waste cooking oil is a sustainable feedstock for biodiesel production.•The properties of the produced fuel ...met EN 14214 and ASTM D 6751.
This paper investigates a new route for intensification of methyl ester synthesis in Malaysia via alkali-catalysed transesterification of waste cooking oil derived from palm olein using a hydrodynamic cavitation reactor. The effects of the oil to methanol molar ratio (1:4–1:7), catalyst loading concentration (0.5–1.25wt%) and reaction temperature (50–65°C) have been investigated using an optimised plate with 21 holes of 1mm diameter and an inlet pressure of 2bar in a 50L of hydrodynamic cavitation reactor assisted by a double diaphragm pump. Optimal conversion of 98.1% was achieved in 15min in a hydrodynamic cavitation reactor with 1:6 molar ratio of oil to methanol, 1wt% of catalyst and 60°C of reaction temperature. It has been observed that a significant reduction in the optimum reaction time (about 6 fold) for transesterification from 90min for mechanical stirring approach to 15min for the hydrodynamic cavitation approach. Optimal yield efficiency of 12.50×10−4g/J was found using hydrodynamic cavitation and it was 8 fold higher than 1.5×10−4g/J when mechanical stirring was used.
The current work reports experimental outcomes about anaerobic digestion (AD) of the organic fraction of catering solid waste to produce biogas and methane yield and solidity of the entire system. ...The possibility of developing AD as an efficient technique for food waste management has also been considered. Inoculation is an established technique to enhance biogas yield through digested sludge, rumen fluid, and slurry recirculation; although this method is proven on cattle manure, however, it is not well studied on food waste. The current study investigates the use of animal intestinal waste as inoculums to enhance biogas yield of food waste. The findings are benchmarked with cattle manure employing known digester materials of carbon steel, aluminum alloy, and at anaerobic mesophilic conditions. The inoculation was varied up to 30% by mass of the substrate materials in each case. The research finds that food waste inoculation was up to 30% using carbon steel reactor under mesophilic temperature conditions (30 ± 1 °C). The food waste produced biogas at a faster rate with a higher yield compared to cattle manure in all digester materials. The biogas yield kept increasing with increasing inoculum ratio reaching optimal at 30% in the case of both food waste and cattle manure with all the digester materials.
Graphic abstract
Cleaner and sustainable water production lead to the development of environmentally friendly adsorbent materials for energy-efficient, cost-effective, and cleaner water production. In this study, the ...biochar derived from the rice husk, wheat straw, and corncob has been used for the adsorptive removal of heavy metals, including the lead (Pb+2) and cadmium (Cd+2). The synthesised biochar was characterised by a different structural and analytical approach. The characterisation of biochar revealed the existence of the combined redox, i.e. reductive and oxidative surface functional groups along with some inert functional groups which play a significant role in donating or accepting an electron to degrade the pollutants in the wastewater. The biochar synthesised in this study was found to be amorphous, and some negligible disorders and defects have been observed in the structure of biochar. The biochar has been highly stable under harsh thermal conditions by sustaining significant weight over a temperature of 700 °C and also be hygroscopic. The biochar rice husk, wheat straw, and corncob demonstrated the lead (Pb+2) adsorption capacity of 96.41%, 95.38%, and 96.92%, while for cadmium (Cd+2), the uptake capacity was found to be 94.73%, 93.68%, and 95.78%. The reported biochar is a cleaner, environmentally friendly, economical, and sustainable alternative to conventional adsorbent materials.
Display omitted
•Biochar derived from rice husk, wheat straw, and corncob was synthesised.•Redox surface functional groups are identified for pollutant degradation.•Biochar found to be amorphous, highly thermally stable, and hygroscopic in nature.•Biochar adsorbed the heavy metals lead (Pb+2) and cadmium (Cd+2) present in wastewater.
Demographic factors, statistical information, and technological innovation are prominent factors shaping energy transitions in the residential sector. Explaining these energy transitions requires ...combining insights from the disciplines investigating these factors. The existing literature is not consistent in identifying these factors, nor in proposing how they can be combined. In this paper, three contributions are made by combining the key demographic factors of households to estimate household energy consumption. Firstly, a mathematical formula is developed by considering the demographic determinants that influence energy consumption, such as the number of persons per household, median age, occupancy rate, households with children, and number of bedrooms per household. Secondly, a geographical position algorithm is proposed to identify the geographical locations of households. Thirdly, the derived formula is validated by collecting demographic factors of five statistical regions from local government databases, and then compared with the electricity consumption benchmarks provided by the energy regulators. The practical feasibility of the method is demonstrated by comparing the estimated energy consumption values with the electricity consumption benchmarks provided by energy regulators. The comparison results indicate that the error between the benchmark and estimated values for the five different regions is less than 8% (7.37%), proving the efficacy of this method in energy consumption estimation processes.
Periprosthetic fractures are associated with significant morbidity and mortality. The "hub and spoke model" consists of a central organisation (the hub) and a series of secondary units (the spokes). ...This study reviews the presentation, management, and outcomes of periprosthetic fractures at a large general district hospital, the Royal Blackburn Hospital.
A retrospective data analysis for patients presenting with periprosthetic fractures from a single general district hospital between January 2011 and December 2020. Details recorded were patient demographics, primary arthroplasty procedure, fracture management, ASA grade, morbidity and mortality, and Unified Classification System for Periprosthetic Fractures (UCSPF).
With 229 periprosthetic fractures, the number tripled in 2020 that admitted in 2011. The mean age was 78.6 years (range 33-100), 151 were females. Seventy-five percent of the fractures were managed locally, while 25% a referral to the higher specialist centre was sort. Of the 57 referrals, 50 were transferred to the hub, 5 were operated on locally, and 2 were managed non-operatively. Higher-level care transfer resulted in a delayed definitive treatment (4.8 versus 12 days, p = 0.001). About 94.4% of patients treated locally had a favourable outcome versus 92% of patients treated at the hub hospital. Cumulative mortality rates for the two sites were comparable.
Most of the patients presenting to the local spoke hospital with periprosthetic fractures were managed in house. For this practice to be preserved, there is a need for future planning, such as maintaining an appropriate skill mix at spoke units. Discussion between specialists at the hub and spoke hospitals reduced patient transfer by 14%.
PDF
