Deadline for manuscript submissions: 31 March 2024.
Topic Introduction
Carbon neutrality, as a state of net-zero CO2 emissions, which can be achieved by counterbalanced all worldwide greenhouse gas emissions by carbon sequestration. Another way to reduce emissions and to pursue carbon neutrality is to offset emissions made in transportation, energy production, agriculture, and industry by reducing them through science-based measures such afforestation and energy saving and reduction emission. This can be done through development of renewable energy, energy efficiency or other clean, low-carbon technologies (https://www.europarl.europa.eu/news/en/headlines/society/20190926STO62270/what-is-carbon-neutrality-and-how-can-it-be-achieved-by-2050). In the 75th session of the UN General Assembly President Xi Jinping proposed that China will increase its National Determined Contribution and adopt more powerful policies and measures. We strive to peak CO2 emissions before 2030 and achieve carbon neutrality before 2060 (http://www.igdp.cn/wp-content/uploads/2021/08/2021-7-21-IGDP-Report-EN-What-to-Expect-in-Chinas-Second-NDC.pdf) (https://news.bloomberglaw.com/environment-and-energy/china-pledges-carbon-neutrality-by-2060-and-tighter-climate-goal). Till the end of December 2021, net zero targets has been set by 136 countries, 115 regions, 235 cities, and 682 companies, which have covered 88% of global greenhouse get emissions, 90% of global GDP and 85% of the world's population (https://news.climate.columbia.edu/2021/12/16/net-zero-pledges-can-they-get-us-where-we-need-to-go/).
Keywords
Worldwide generation of crop residues exceeds four billion tonnes per year, much of which is openly burnt or landfilled, with consequences for air quality, greenhouse-gas emissions, and soil organic matter. Thermochemical conversion of these residues to biochar offers a valorisation route with the potential to contribute simultaneously to water and soil remediation and to durable carbon storage. This structured narrative review consolidates progress on agricultural waste derived biochar (AWDB) reported between 2020 and 2026. Slow pyrolysis, fast pyrolysis, microwave-assisted pyrolysis, and hydrothermal carbonisation are compared in terms of operating conditions, yield, and product attributes. Activation routes (steam, CO2, KOH, ZnCl2, H3PO4) and post-synthetic modifications (heteroatom doping, metal impregnation, magnetic functionalisation) are evaluated against porosity, surface chemistry, and adsorbate selectivity. Applications span heavy-metal, dye, antibiotic, and CO2 removal, together with soil amendment and carbon sequestration. Persistent limitations are identified, including over-reliance on equilibrium capacities, inconsistent test protocols, sparse multicomponent data and incomplete life-cycle accounting. The distinction between biochar, activated biochar, and biochar-derived activated carbon is applied consistently, and the safety profile of the material—residual pyrolysis organics, potentially toxic elements, release of impregnated metals, and management of pollutant-loaded spent adsorbent—is treated as integral to the assessment. Priorities are proposed for standardised evaluation, mechanism-guided synthesis, data-driven design, and techno-economic assessment.
The escalating impacts of global warming have raised concerns at local and global levels, necessitating urgent mitigation efforts, particularly among households in urban settings. However, limited information on household energy consumption and its associated carbon footprint may constrain effective climate mitigation and policy development in Bauchi metropolis. This study assessed household energy consumption in Bauchi metropolis to establish its carbon footprint and inform policy development amid evident climate change. The study adopted a descriptive survey approach involving questionnaires and observational field measurements using a weighing scale to establish the average unit weight of energy sources across six wards. A two stage sampling technique involving cluster and purposive sampling was adopted. Descriptive statistics and the Intergovernmental Panel on Climate Change (IPCC) guidelines were used to analyse the data and estimate the related carbon footprint. The result of 403 analysed responses revealed that the average annual carbon footprint from firewood, charcoal, grid electricity, LPG, petrol, diesel, kerosene, and sawdust was 6.61 tCO2 per household, with firewood and charcoal identified as priority areas for emission reduction. The study concluded that household energy consumption contributes to carbon emissions in the Bauchi metropolis and therefore recommends targeted interventions should reduce dependence on firewood and charcoal and promote cleaner household energy sources.
