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An ‘artificial leaf’ that turns carbon into fuel
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An ‘artificial leaf’ that turns carbon into fuel has been created
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SCIENTISTS have created an ‘artificial leaf’ to fight climate change by inexpensively converting harmful carbon dioxide (CO2) into a useful alternative fuel. The new technology was inspired by the way plants use energy from sunlight to turn carbon dioxide into food.
“We call it an artificial leaf because it mimics real leaves and the process of photosynthesis,” said Yimin Wu, an engineering professor at the University of Waterloo who led the research. “A leaf produces glucose and oxygen. We produce methanol and oxygen.”
Making methanol from carbon dioxide, the primary contributor to global warming, would both reduce greenhouse gas emissions and provide a substitute for the fossil fuels that create them.
The key to the process is a cheap, optimized red powder called cuprous oxide. Engineered to have as many eight-sided particles as possible, the powder is created by a chemical reaction when four substances – glucose, copper acetate, sodium hydroxide and sodium dodecyl sulfate – are added to water that has been heated to a particular temperature.
The powder then serves as the catalyst, or trigger, for another chemical reaction when it is mixed with water into which carbon dioxide is blown and a beam of white light is directed with a solar simulator.
Engineering professor Yimin Wu. (PHOTO: Brian Caldwell, University of Waterloo)
“This is the chemical reaction that we discovered,” said Yimin, who has worked on the project since 2015. “Nobody has done this before.”
The reaction produces oxygen, as in photosynthesis, while also converting carbon dioxide in the water-powder solution into methanol. The methanol is collected as it evaporates when the solution is heated. An hour-long chemical reaction creates the engineered red powder that is the key to new technology to turn carbon dioxide into fuel.
Next steps in the research include increasing the methanol yield and commercializing the patented process to convert carbon dioxide collected from major greenhouse gas sources such as power plants, vehicles and oil drilling.
“I’m extremely excited about the potential of this discovery to change the game,” said Yimin, a professor of mechanical and mechatronics engineering, and a member of the Waterloo Institute for Nanotechnology. “Climate change is an urgent problem and we can help reduce CO2 emissions while also creating an alternative fuel.”
Power up your planting blends
Incitec Pivot Fertilisers is introducing a powerful addition to DAP that will help growers keep the nitrogen where it’s needed for longer, drive phosphorus uptake and potentially improve crop yields and quality. Our new product, eNpowerTM 18:20, is DAP coated with a patented new formulation ammonium stabiliser, DMPG. It works just like ENTEC®, by inhibiting the nitrifying bacteria in the soil, stopping them from converting the ammonium nitrogen to nitrate nitrogen. If you’ve had experience with ENTEC, you’ll know the advantages this can bring. It can mean better nitrogen efficiency, reduced losses from leaching, runoff and denitrification, better protection in the wet and a nitrogen supply that better matches crop demand. Incitec Pivot Fertilisers developed the new formulation ammonium stabiliser because DAP and ENTEC were not chemically compatible. DAP is a key planting fertiliser for sugar cane and range of other tropical and temperate crops, so this is an important step towards better outcomes for more growers.
Matching nitrogen supply with crop demand
The best fertiliser programs match nutrient supply with crop demand to avoid over and under application and to help crop growth progress towards optimum yields and quality. This is easier said than done!
In most vegetable and summer crops, nitrogen demand increases after planting as the crop grows, then peaks at 40-70 days after planting. If most of the nitrogen is applied at planting or within the first month, this can result in a lot of nitrate nitrogen available in the soil that the crop can’t yet use. This nitrate nitrogen is vulnerable to losses, particularly in the case of heavy rainfall or unexpected rain following irrigation. Nitrate leaching occurs when nitrates move down through the soil profile beyond the root zone. Leaching losses can be significant, particularly on lighter soil types with a cation exchange capacity (CEC) of 4 or less. Denitrification occurs where soil oxygen has been depleted in high soil moisture situations, and results in the loss of nitrogen to the atmosphere. In cane, nitrogen is important for early vigour and successful establishment, so protecting the planting fertiliser by using eNpower 18:20 may help better match nitrogen requirements between planting and the last side dress opportunity prior to out of hand stage. Using eNpower 18:20 provides an alternative for growers looking to better match nitrogen supply with crop demand by keeping the nitrogen in the soil in the ammonium form until it is needed by the crop. Ammonium nitrogen is not subject to leaching or denitrification losses. Most crops, including sugar cane and maize, prefer ammonium nutrition, so there is no delay in the availability of nitrogen. In fact, eNpower 18:20 could help promote quality and consistency in produce in some crops by reducing the incidence of nitrate flushes.
Using eNpower 18:20 is a good way to set crops up for success, whatever the season. Australia’s tropical and sub-tropical cropping regions are subject to unpredictable rainfall, and while good rains can lead to good yields, they can also rob the crop of nitrogen. Using eNpower 18:20 helps protect nutrients for when the crop needs them most.
Driving phosphorus uptake
Phosphorus is essential for photosynthesis, plant growth and crop development and is the most expensive macro nutrient. Switching from DAP to eNpower 18:20 has the potential to increase the uptake of phosphorus by two mechanisms. Firstly, phosphorus uptake is strengthened when crops take up ammonium nitrogen rather than nitrate nitrogen. As the plants absorb the positively charged ammonium nitrogen, they naturally compensate by seeking out negatively charged nutrients such as orthophosphate (phosphorus). This effect can give emerging cane crops a better start.
The nitty gritty
As with ENTEC, eNpower 18:20 will only be available from accredited advisers who have proven their understanding of the product by satisfactorily completing a training course and assessment. This helps ensure the best practice use of eNpower 18:20 for the best possible results in crop. Growers will be able to use eNpower 18:20 as a straight or in blends. As with any fertiliser decision, it should be based on a sound understanding of the soil nutrient status and the Secondly, the use of ammonium stabilisers promotes rhizosphere acidification, via a process referred to as partial ammonium nutrition. The rhizosphere is the specific zone immediately around each plant root (generally within 1 mm distance). Ammonium stabilisers make only pH value requirements of the crop. Always arrange soil testing and analysis through the Nutrient Advantage® laboratory to determine an appropriate fertiliser strategy. In Incitec Pivot Fertilisers’ incubation trials, the DMPG ammonium stabiliser has been shown to be effective on other nitrogen fertilisers present in blends with eNpower 18:20. However, to ensure the ammonium stabiliser works effectively in a blend, eNpower 18:20 must provide at least 50% of the total nitrogen in the blend. the rhizosphere slightly more acidic while the DMPG is active. This ‘very localised’ change to pH improves phosphorus and zinc availability. See table below. Rhizosphere influences, of which rhizosphere acidification is one example, can greatly benefit
Nitrate Ammonium Ammonium with N inhibitor crop production.
Root distance
6.6 5.7
Rhizosphere
6.6 5.6
6.6 4.5
P
123 342
586
Fe
55 71
166
Mn
8 20
35
Zn
7 13
19
Cu
1.4 2.0
4.6
K
903 1127
1080
Table 1: Influence of the nitrogen form on the uptake of other nutrients. Source: Adapted from Thomson et al. (1993) J. Plant Nutr. 16, 493-506.
Nutrient uptake (µg/m root length)
TO FIND OUT MORE ABOUT ENPOWER 18:20 Read the eNpower 18:20 brochure or Contact 0428 111 471 or rob.dwyer@incitecpivot.com.au
Starter fertilisers for cane vary widely depending on soil fertility and the needs of the crop. Some popular planting fertiliser blends such as CK 55, CK 55(Zn), CK 66 and DAP(S) can be made using the new eNpower 18:20 instead of DAP.
Urea blends are not recommended for use at planting in cane. ENTEC urea will continue to be recommended for sidedressing in plant cane situations and in ratoon cane where growers are looking to protect their nitrogen investment against losses.
eNPowerTM is a trademark of Incitec Pivot Limited®. ENTEC is a registered trademark of EuroChem Agro GmbH®. Nutrient Advantage is a registered trademark of Incitec Pivot Limited®.
Using ENTEC in dry seasons
This year, early ratoon growth in many cane growing districts has been slow due to a combination of dry conditions and cool overnight temperatures, even in the north. This has put fertiliser programs behind schedule. The dry weather has also meant that growers and their advisers have not been thinking about the risk of nitrogen losses from leaching, denitrification or runoff. This is a case of “out of sight, out of mind”. But actually, ENTEC has a good record of success when applied in the dry. That’s because it doesn’t stay dry forever.
How long ENTEC remains active in the soil depends on biological activity. When soils are dry, ENTEC remains active for longer. This means ENTEC is likely to still be actively inhibiting the nitrification of applied fertilisers even after a few months of dry weather. This is particularly relevant this season, with the Bureau of Meteorology predicting a delayed start to the monsoon, related to the late retreat (movement south) of the Southwest Indian monsoon. Often, when there is a dry start to the season like we’ve had this year, the next rain event is a big one. That’s when ENTEC delivers good results for growers, because the nitrogen is stabilised as ammonium and available in the root zone for use when the crop starts growing. For example, in a replicated small plot trial in the Herbert district in 2013/14, using ENTEC increased cane and sugar yields over a traditional urea blend, even though it was dry for two months after the fertiliser application (Figures 1&2). It began raining on Boxing Day and then four months later, Cyclone Ita hit, providing another major deluge. At the end of the season, where 150 kg/ha of nitrogen was applied as an ENTEC urea blend, 81.5 t/ha of cane was cut with a sugar yield of 11.2 t/ha. The same rate of nitrogen supplied as a urea blend yielded 53.7 t/ha of cane and a sugar yield of 8.4 t/ha. The losses from the untreated urea blend appear to have been so significant that even applying a higher rate of nitrogen did not improve yield.
90 80 70 60 50 40 30 20 10 0 Cane yield Response (t/ha) comparing ENTEC and urea blends, Herbert district, 2013/14
a bc cd
ab e
Zero N 110 kg/ha N as urea blend 110 kg/ha N as ENTEC urea blend 150 kg/ha N as urea blend 150 kg/ha N as ENTEC urea blend
Figure 1: ENTEC urea provided higher yields despite a dry start to the season in 2013.
Source: Herbert Sustainable Farming Systems group, the Queensland government and Herbert Cane Productivity Services Limited. Significant difference shown by letter at P <0.05.
12 11 10 9 8 7 6 5 4 3 2 1 0 Sugar yield response (t/ha) comparing ENTEC and urea blends, Herbert district, 2013/14 d d
a abc ab
Zero N 110 kg/ha of N as urea blend 110 kg/ha of N as ENTEC urea blend 150 kg/ha of N 150 kg/ha of N as urea blend as ENTEC urea blend
Figure 2: Sugar yield response (t/ha) from ENTEC and urea blends, Herbert district, 2013/14
Source: Herbert Sustainable Farming Systems group, the Queensland government and Herbert Cane Productivity Services Limited. Significant difference shown by letter at P <0.05. * Sugar yield was detrimentally influenced by lodging and the interaction of Cyclone Ita and wind resistance on the higher cane yield grown with ENTEC performance up to the onset of this weather event.
It was a similar story after another dry start to the season in Innisfail in 2017/2018. In January 2018 there were a few moderate rainfall events. This was 42 days after the fertiliser was applied. However, it was much later (77 days after fertiliser application) that the first significant rainfall event occurred (170 mm in February 2018). Using an ENTEC urea blend provided statistically Cane yield response (t/ha) comparing ENTEC and urea blends, Innisfail, 2017/18 60 50 40 30 20 10 0 ENTEC is typically active across all of the unpredictable seasonal conditions cane growers face. Where agricultural soils have a pH(w) of more than 4.5,1 nitrogen fertilisers are better protected from leaching, denitrification and runoff with ENTEC. If the fertilisers are incorporated into the soil with 10 cm of compacted soil coverage, the nitrogen is also protected against volatilisation losses. Consider incorporation with a StoolZippa® as a means of more consistently achieving References: 1 Dwyer R, “Understanding ENTEC in a sugar cane system” (2019) https://www.qsl.com.au/sugar-prices significant increases in cane and sugar yields compared with an untreated urea blend, based on the Six Easy Steps nitrogen rate of 110 kg/ha (Figures 3&4). The ENTEC treatment at 110 kg/ha of nitrogen yielded 72 t/ha of cane and 12.2 t/ha of sugar. The untreated urea blend at the same rate yielded 60 t/ha cane and 10.4 t/ha of sugar. ENTEC was able to deliver yield increases of 20% (t/ha of
90 80 70
a abc bcd
ab cd
Zero N 82.5 kg/ha of N 82.5 kg/ha of N 110 kg/ha of N as urea blend as ENTEC as urea blend urea blend 110 kg/ha of N as ENTEC urea blend
Figure 3: ENTEC urea outperformed urea at Innisfail in a dry season.
Source: Assessment of potential benefits of EEFs in sugarcane cropping systems by Wejin Wang et al, Queensland Department of Environment and Science. Significant difference shown by letter at P <0.05.
cane) and 17% (t/ha of sugar) respectively. Sugar yield response (t/ha) comparing ENTEC and urea blends, Innisfail, 2017/18cd
12 11 10 9 8 7 6 5 4 3 2 1
0 bcd abc ab
a
Zero N 82.5 kg/ha of N 82.5 kg/ha of N 110 kg/ha of N as urea blend as ENTEC as urea blend urea blend 110 kg/ha of N as ENTEC urea blend
Figure 4: Sugar yield response (t/ha) from ENTEC and urea, Innisfail, 2017/18
Source: Assessment of potential benefits of EEFs in sugarcane cropping systems by Wejin Wang et al, Queensland Department of Environment and Science. Significant difference shown by letter at P <0.05.
the required compacted soil cover. Managing volatilisation is the first step towards achieving the best potential from ENTEC use. Additionally, the StoolZippa can reduce losses of nitrogen from runoff. Considering the current sugar price,2 growers need to optimise potential yields through better nitrogen use efficiency. Every tonne matters. At current prices, growing one extra tonne of cane/ha could cover the price
https://www.incitecpivotfertilisers.com.au/news-and-insights/agronomic-insights/sugar/understanding-entec-in-a-sugar-cane-system 2 Queensland Sugar Limited (QSL) daily price on 31 October 2019 of $393.88/t difference between using urea or ENTEC urea.3 3 Assumes the daily price from 31 October 2019 of $393.88/t (as above) and a minimum CCS of 10%.
Current average CCS is 14.07% (Australian Sugar Milling Council 27 October 2019).
Assuming an application of 150 kg/ha of urea, the additional spend on ENTEC is $39/ha.
FOR MORE INFORMATION ABOUT USING ENTEC THIS SEASON feel free to give me a call to discuss on 0428 111 471 or email rob.dwyer@incitecpivot.com.au
INDUSTRY IN FIGURES
