Soil carbon in the field, carbon and ammonia in the cell
Three studies measure carbon and energy chemistry in the field and the cell: soil carbon rising at four of seven Illinois sites, seawater mineralisation for more than 120 hours, and higher Faradaic efficiency in ammonia synthesis.
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Soil carbon returning at four of seven sites
Ilsa B. Kantola of the University of Illinois and colleagues measured soil organic carbon to a depth of one metre under mature perennial bioenergy crops and reported increases in the first five years at four of seven Illinois sites. Mean stocks, in megagrams of carbon per hectare, were 146 under prairie, 107 under Miscanthus, 97.9 under Panicum virgatum and 87.7 under maize. Carbon isotope analysis attributes the gains to the perennial crops themselves. According to Phys.org's account of the study published in Geoderma, the perennial stocks sit between depleted farmland and native prairie, so the measured gain partly closes the deficit maize opened. The crops had been established for under eleven years and monitoring ran five years. The announcement does not explain what set the three sites without gains apart. The result the study highlights is that stocks rose even while the crops continued to be harvested every year. Field-scale carbon can therefore accumulate in soil while an energy crop is still taken off each season; the Illinois measurement shows harvest and rising soil stocks reported together in the same window.[1]
A cell that mineralised seawater carbon for more than 120 hours
Researchers at KAIST and MIT reported an electrochemical cell that fixes dissolved inorganic carbon from seawater as calcium carbonate. In its bundled hollow-fibre electrodes the mineral forms outside rather than on the electrode surface, while hydrogen bubbles released during the reaction continuously clean it. According to Phys.org's account of the study published in Advanced Energy Materials, laboratory tests using Jeju lava seawater removed between 80 percent and 90 percent of dissolved inorganic carbon and ran without interruption for more than 120 hours. The team also reports up to 54 percent lower electricity use than existing approaches, plus high-purity hydrogen and magnesium hydroxide as by-products. This is a laboratory-scale cell. The announcement gives no cost per tonne, no seawater throughput and no ecological assessment of returning the treated water, so removal at a climate-relevant scale has not been demonstrated in this report. The first author is Inhwan Park. The reported setup runs carbon chemistry continuously inside a cell and carries it out as solid mineral rather than leaving it dissolved.[2]
Ammonia Faradaic efficiency and a shared measurement plane
A team led by Yousung Jung in the Department of Chemical and Biological Engineering at Seoul National University reported a design rule for the electrochemical reaction that makes ammonia from nitrogen, water and electricity. Sterically crowding the proton donor raises the energy barrier for the Volmer reaction, the first step in hydrogen formation, while nitrogen reduction is barely affected because protons can still reach nitrogen molecules that protrude outward from the catalyst surface. According to Phys.org's account of the study published in the Journal of the American Chemical Society, Faradaic efficiency rose from around 70 percent to nearly 100 percent and held across a wide voltage range. Faradaic efficiency reports where the current went, not how much ammonia was made. The announcement gives no current density, production rate or operating lifetime. The first author is Dongmin Park; the team names finding more active catalyst materials as the next step. Taken together, the three developments show carbon and energy chemistry being measured under load in the field and in the cell: rising soil organic carbon stocks under Illinois perennials while harvest continues, mineralisation lasting more than a hundred hours in a seawater cell, and a higher share of current directed to product in an ammonia cell. What is shared is a set of pathways that hold, mineralise or reduce carbon and nitrogen under continuous operation.[1], [2], [3]
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