The Utilisation of Solid Fuels Derived from Waste Pistachio Shells in Direct Carbon Solid Oxide Fuel Cells.
The comprehensive results regarding the physicochemical properties of carbonaceous materials that are obtained from pistachio shells support their usage as solid fuels to supply direct carbon solid oxide fuel cells (DC-SOFCs). The influence of preparation conditions on variations in the chemical composition, morphology of the biochar powders, and degree of graphitization of carbonaceous materials were investigated. Based on structural investigations (X-ray diffraction analysis and Raman spectroscopy), it was observed that disordered carbon particles developed during the application of thermal treatments. The use of X-ray fluorescence enabled a comparative analysis of the chemical composition of the inorganic matter in biocarbon-based samples. Additionally, the gasification of carbonaceous-based samples vs. time at a temperature of 850 °C was investigated in a H2O or CO2 gas atmosphere. The analysis demonstrated the conversion rate of biochar obtained from pistachio shells to H2, CH4 and CO during steam gasification. The electrochemical investigations of the DC-SOFCs that were supplied with biochars obtained from pistachio shells were characterized by satisfactory values for the current and power densities at a temperature range of 700-850 °C. However, a higher power output of the DC-SOFCs was observed when CO2 was introduced to the anode chamber. Therefore, the impact of the Boudouard reaction on the performance of DC-SOFCs was confirmed. The chars that were prepared from pistachio shells were adequate for solid fuels for utilization in DC-SOFCs. https://doi.org/10.3390/ma14226755
Utilization of the UAE date palm leaf biochar in carbon dioxide capture and sequestration processes
This paper evaluates the potential use of date palm leaf biochar as a climate change solution through CO2 capture and sequestration. The pyrolysis of date palm leaf was performed at different temperatures 300°, 400°, 500°, and 600 °C. The physicochemical characteristics of the synthesized biochar were examined using Scanning Electron Microscopy (SEM) with Energy Dispersive X-Ray Analysis (EDX), Fourier transforms infrared spectroscopy (FTIR), Thermogravimetric analysis (TGA), and X-ray diffraction analysis (XRD). Direct gas-solid interaction was carried out in an integrated Fluidized Bed Reactor (FBR), connected with a gas analyzer for maximum and effective mixing between the biochar and CO2. LabView program was used as data acquisition for an instantaneous calculation of CO2 adsorption. This study showed that the date palm biochar as porous carbon-based materials has high CO2 adsorption capacity through physisorption and chemisorption progressions. The adsorption results showed a maximum CO2 capture percentage of 0.09 kg CO2/kg, 0.15 kg CO2/kg, 0.20 kg CO2/kg, and 0.25 kg CO2/kg palm biochar synthesized at 300 °C, 400 °C, 500 °C, and 600 °C, respectively. This paper paid attention to the inexpensive technology applied in CO2 sequestration, where fluidization provides well mixing of biochar particles with low operation cost. https://doi.org/10.1016/j.jenvman.2021.113644
Improved fertiliser management to reduce the greenhouse-gas emissions and ensure yields in a wheat-peanut relay intercropping system in China.
Over the last century, anthropogenic greenhouse-gas (GHG) emissions have changed the global climate, and agriculture plays an important role in the global flux of GHG. Agricultural management practices, such as split N applications and the use of controlled-release fertilisers have significantly increased the crop yield and N-use efficiency by balancing the N demand of crops and the N availability of soils. However, the impacts of these practices on GHG emissions (in particular in wheat-peanut relay intercropping systems) have not been evaluated in detail. In this study, a common compound fertiliser and a controlled release compound fertiliser (CRF) were used the day prior to sowing, at the jointing stage of wheat and at the peanut anthesis stage in ratios of 50-50-0% (JCF100), 35-35-30% (JCF70) and 35-35-30% (JCRF70), with a control treatment of 0 kg ha-1. The findings demonstrated that treatment JCF70 achieved increases in yields of 9.7% and 14.6% for wheat grain and peanut pod, respectively, compared to treatment JCF100; however, this treatment also significantly increased soil emissions of CO2 and N2O. In addition, cumulative emissions of CO2 and N2O were higher in the peanut growing season by 74.4 and 31.7%, respectively, than in the wheat growing season owing to the relatively higher soil temperature during the former season. Fertilisation combined with irrigation, was found to be the main cause of GHG emissions. Under the same fertiliser rate and N-management style, JCRF70 further increased the yield of peanut pods and the total combined yield of peanut and wheat by 10.3% and 8.9%, respectively, compared to treatment JCF70. The cumulative CO2 and N2O emissions in treatment JCRF70 were 20.4-45.4% less than those in treatment JCF70. The total global warming potentials of CO2 and N2O were lowest in treatment JCRF70 owing to it providing the highest grain yield. Therefore, N application with three splits, together with the use of a slow-release fertiliser, may be a simple and effective approach to enhance the grain yield whilst reducing the GHG emissions. https://doi.org/10.1007/s11356-021-17078-1
Green production of hydrochar nut group from waste materials in subcritical water medium and investigation of their adsorption performance for Crystal Violet.
This study evaluates the production of hydrochars from the outer shells of the nut group (peanut, hazelnut, walnut, and pistachio) in an eco-friendly SWM medium and their effects as adsorbents on the removal of crystal violet (CV) from an aqueous solution. The prepared hydrochars were characterized using Brunauer Emmett-Teller (BET) analysis, scanning electron microscope (SEM), Fourier transforms infrared spectroscopy (FTIR), and zeta potential. The adsorption process was optimized based on pH, adsorbent dose, dye concentration, and contact time. The hazelnut hydrochar was found to have the maximum removal efficiency (91%). Optimum conditions were pH of 8, particle size <45um, adsorption time of 60 min, and dye concentration of 25 mg/L. The results of all hydrochars were fitted to the second-order kinetics. Langmuir, Freundlich, and Redlich - Peterson isotherms models were used to explain the relationship between adsorbent and adsorbate. For all hydrochars, CV adsorption was found to be feasible and inherently spontaneous. The use of materials with no commercial value like; the outer shells of the nut group, is considered a method for waste reduction using the SWM method. https://doi.org/10.1002/wer.1659
Selective limb removal pruning and reflective ground covers improve light and crop distributions in the lower zone of ‘Nonpareil’almond trees but not total yield.
Conventional planting and management systems for almond (Prunus dulcis (Mill.) D. A. Webb) orchards involve trees trained from an early age to produce multiple large scaffold branches, which in mature orchards form closed light inefficient canopies. Treatments included a single round of selective limb removal pruning applied at the start of the research to remove the large scaffold branches that cause shading between trees. Treatments were applied to two groups of 5-year-old ‘Nonpareil’ trees on ‘Nemaguard’ rootstock planted at 6 × 3 m spacing (556 trees/ha) in the Riverland region of South Australia. Each year, reflective ground covers were installed beneath one group of pruned trees to reflect light back into the lower canopy zones. A third group of control trees were left unpruned without reflective ground covers. Yield, kernel quality and light transmission within canopy zones were monitored for 3 subsequent years. Results demonstrated that in control trees, less than 10% of incoming sunlight was transmitted to lower canopy zones. This was insufficient to ensure cropping in these zones. Although pruning selected limbs and using reflective ground covers increased the amount of light and thus yields in the lower canopy zones, this was not sufficient to increase total tree yield nor improve kernel quality. Furthermore, the fruit in these lower zones were not ready for harvest until 2–3 weeks after the main crop. https://doi.org/10.1016/j.scienta.2021.110508
Date Fruit Processing Waste and Approaches to Its Valorization: A Review.
In the Middle East and North Africa, dates are a traditional and economically valuable crop, playing an essential role in people's daily diets. Date fruit production and related processing industry generate a large quantity of waste; for illustration, the date juicing industry produces roughly 17-28% Date press cake (DPC), which is mainly discarded in open lands and drains. Considering the generation volume and the nutrient content of DPC, this organic by-product stream can be valorized through the production of a wide range of products with a great market appeal, such as volatile fatty acids, activated carbon, organic acids, etc. To provide an insight into the feasibility of the application DPC as a green precursor for various chemical and biological processes, the chemical and nutritional composition of dates and DPC, an overview of the date processing industries, and common practices conducted for DPC valorization addressed and thoroughly discussed, in this review. https://doi.org/10.1016/j.biortech.2021.125625
Experimental and Theoretical Studies on Extract of Date Palm Seed as a Green Anti-Corrosion Agent in Hydrochloric Acid Solution.
Extracts from plant materials have great potential as alternatives to inorganic corrosion inhibitors, which typically have harmful consequences. Experimental and theoretical methodologies studied the effectiveness of agricultural waste, namely, date palm seed extract as a green anti-corrosive agent in 0.5 M hydrochloric acid. Experimental results showed that immersion time and temperature are closely related to the effectivity of date palm seed as a corrosion inhibitor. The inhibition efficiency reduced from 95% to 91% at 1400 ppm when the immersion time was increased from 72 h to 168 h. The experimental results also indicated that the inhibition efficiency decreased as the temperature increased. The presence of a protective layer of organic matter was corroborated by scanning electron microscopy. The adsorption studies indicated that date palm seed obeyed Langmuir adsorption isotherm on the carbon steel surface, and Gibbs free energy values were in the range of -33.45 to -38.41 kJ·mol-1. These results suggested that the date palm seed molecules interacted with the carbon steel surface through mixture adsorption. Theoretical calculations using density functional theory showed that the capability to donate and accept electrons between the alloy surface and the date palm seed inhibitor molecules is critical for adsorption effectiveness. The HOMO and LUMO result indicated that the carboxyl (COOH) group and C=C bond were the most active sites for the electron donation-acceptance type of interaction and most auxiliary to the adsorption process over the Fe surface. https://doi.org/10.3390/molecules26123535
Pyrolysis of Almond (Prunus amygdalus) Shells: Kinetic Analysis, Modelling, Energy Assessment and Technical Feasibility Studies.
The aim of this work was to study the thermogravimetric analysis through the pyrolysis of almond (Prunus amygdalus) shells for evaluating its potential for bioenergy at different heating rates (10, 25, and 50 K min-1). The activation energy values for the process were of the range of 153.0, 152.02, and 152.73 kJ mol-1 as calculated by Kissenger-Akahira-Sunrose (KAS), Ozawa-Flynn-Wall (OFW) and Starink models respectively. The change in the Gibbs free energy was ~181 kJ mol-1. Diffusion-based reaction, followed by the chemical reaction mechanism,was dominant thermal degradation as envisaged by the Coats-Redfern method. The validation of the experiments was accomplished through the artificial neural network, reiterating its further usage in any conversional studies of biomass. A difference of < 10 kJ mol-1 between the values of activation energy and enthalpy of the degradation reaction indicated favourable product formation. The results offer potential application of almond shells for energy production through pyrolysis. https://doi.org/10.1016/j.biortech.2021.125466
Healthier and more sustainable diets: What changes are needed in high‐income countries?.
Debate persists around the food production and dietary changes needed to improve sustainability of our global food system. We reviewed 29 studies in high-income countries that used various methodologies to define a healthier, more sustainable diet. Diets aligned with dietary guidelines, containing less meat and higher amounts of plant-derived foods (vegetables, pulses [beans/lentils], fruit, wholegrains, nuts, seeds) would likely offer environmental benefits (~20–50% lower greenhouse gas emissions [GHGE] and land use) and improve population health, although may not reduce water footprint. Changes in consumption of milk products and eggs were inconsistent in optimisation studies, perhaps reflecting trade-offs between their nutrient contribution and environmental impact. Foods high in fat, salt and/or sugar, and beverages (e.g. tea, coffee and fruit juices) contributed substantially to environmental footprints in some studies. Vegetarian and vegan diets may deliver larger environmental benefits, but are unlikely to be widely adopted, and may reduce intakes and/or bioavailability of some essential nutrients (e.g. iron, zinc, iodine and B12). We recommend adherence to existing government dietary guidelines as a more realistic goal to improve environmental (e.g. 30% lower GHGE in the UK) and health impacts of diets, recognising that adherence is currently relatively poor. Wider considerations include: context-specific nutritional, health, cost and cultural needs; need for public engagement to understand barriers/motivators; better understanding of the wider implications and trade-offs linked to dietary and food system changes and how these can be managed, so that benefits in high-income countries do not come at the expense of greater ‘outsourced’ environmental impacts in other regions. https://doi.org/10.1111/nbu.12518
Sugarcane/peanut intercropping system improves physicochemical properties by changing N and P cycling and organic matter turnover in root zone soil
Background: The sugarcane/peanut intercropping system is a specific and efficient cropping pattern in South China. Intercropping systems change the bacterial diversity of soils and decrease disease rates. It can not only utilized light, heat, water and land resources efficiently, but also increased yield and economic benefits of farmers.
Methods: We determined soil nutrients, enzymes and microbes in sugarcane/peanut intercropping system, and analyzed relevance of the soil physicochemical properties and the genes involved in N and P cycling and organic matter turnover by metagenome sequencing.
Results: The results showed that sugarcane/peanut intercropping significantly boosted the content of total nitrogen, available phosphorus, total potassium, organic matter, pH value and bacteria and enhanced the activity of acid phosphatase compared to monocropping. Especially the content of available nitrogen, available phosphorus and organic matter increased significantly by 20.1%, 65.3% and 56.0% in root zone soil of IP2 treatment than monocropping treatment. The content of available potassium and microbial biomass carbon, as well as the activity of catalase, sucrase and protease, significantly decreased in intercropping root zone soil. Intercropping resulted in a significant increase by 7.8%, 16.2% and 23.0% in IS, IP1 and IP2, respectively, of the acid phosphatase content relative to MS. Metagenomic analysis showed that the pathways involved in carbohydrate and amino acid metabolism were dominant and more abundant in intercropping than in monocropping. Moreover, the relative abundances of genes related to N cycling (glnA, GLUD1_2, nirK), P cycling (phoR, phoB) and organic matter turnover (PRDX2_4) were higher in the intercropping soil than in the monocropping soil. The relative abundance of GLUD1_2 and phoR were 25.5% and 13.8% higher in the IP2 treatment respectively,and bgIX was higher in IS treatment compared to the monocropping treatment. Genes that were significantly related to phosphorus metabolism and nitrogen metabolism (TREH, katE, gudB) were more abundant in intercropping than in monocropping.
Conclusion: The results of this study indicate that the intercropping system changed the numbers of microbes as well as enzymes activities, and subsequently regulate genes involved in N cycling, P cycling and organic matter turnover. Finally, it leads to the increase of nutrients in root zone soil and improved the soil environment.