A whopping 3.8 million tons of citrus peels go to waste each year. This is annoying for processors, who have to figure out some way to dispose of them, and disheartening for us as lovers of all weird ways to repurpose food waste.

But a group of Spanish researchers have come up with a new use for this so-called waste: as a material in wastewater treatment facilities that can filter out bad metals and other pollutants. This first test was done with copper, a potentially toxic heavy metal present in some water.

These researchers have figured out a process to turn citrus peels – oranges and grapefruits were tested, though the process could in the future apply to other peels – into a sort of burnt-umber sediment by first dehydrating then, then chemically treating them to mess with the acid/base ratio and their texture. That enables the peels to filter out exactly the metals we don’t want in our water, and to enhance their adsorption. (Not absorption, mind you: adsorption describes a filtering process, in which undesired materials can’t make it through a material and instead form a sort of film on the outside.)

The final powdery product looks a bit like the carbon-based filter material you might find on the inside of a Brita filter, and for good reason: it has a similar effect.

Put into a wastewater treatment system, the peel-based material showed promise for filtering out nasty metals in water – enough so that the researchers believe it could actually compete with activated carbon (the stuff in your Brita filter). Here’s a fun fact: the carbon in the Brita filter is made by burning up coconut hulls. Another nice use of food waste!

Notify of

Label

Name*

Email*

Website

Label

Name*

Email*

Website

This site uses Akismet to reduce spam. Learn how your comment data is processed.

0 Comments

Most Voted

Newest Oldest

Inline Feedbacks

View all comments

Facebook
Instagram
LinkedIn
X

Republish!

Republish our articles for free, online or in print, under a Creative Commons license.

Republish this article

This work is licensed under a Creative Commons Attribution-NoDerivatives 4.0 International License.

Want to republish a Modern Farmer story?

We are happy for Modern Farmer stories to be shared, and encourage you to republish our articles for your audience. When doing so, we ask that you follow these guidelines:

Please credit us and our writers

For the author byline, please use “Author Name, Modern Farmer.” At the top of our stories, if on the web, please include this text and link: “This story was originally published by Modern Farmer.”

Please make sure to include a link back to either our home page or the article URL.

At the bottom of the story, please include the following text:

“Modern Farmer is a nonprofit initiative dedicated to raising awareness and catalyzing action at the intersection of food, agriculture, and society. Read more at <link>Modern Farmer</link>.”

Use our widget

We’d like to be able to track our stories, so we ask that if you republish our content, you do so using our widget (located on the left hand side of the article). The HTML code has a built-in tracker that tells us the data and domain where the story was published, as well as view counts.

Check the image requirements

It’s your responsibility to confirm you're licensed to republish images in our articles. Some images, such as those from commercial providers, don't allow their images to be republished without permission or payment. Copyright terms are generally listed in the image caption and attribution. You are welcome to omit our images or substitute with your own. Charts and interactive graphics follow the same rules.

Don’t change too much. Or, ask us first.

Articles must be republished in their entirety. It’s okay to change references to time (“today” to “yesterday”) or location (“Iowa City, IA” to “here”). But please keep everything else the same.

If you feel strongly that a more material edit needs to be made, get in touch with us at [email protected]. We’re happy to discuss it with the original author, but we must have prior approval for changes before publication.

Special cases

Extracts. You may run the first few lines or paragraphs of the article and then say: “Read the full article at Modern Farmer” with a link back to the original article.
Quotes. You may quote authors provided you include a link back to the article URL.
Translations. These require writer approval. To inquire about translation of a Modern Farmer article, contact us at [email protected]
Signed consent / copyright release forms. These are not required, provided you are following these guidelines.
Print. Articles can be republished in print under these same rules, with the exception that you do not need to include the links.

Tag us

When sharing the story on social media, please tag us using the following: - Twitter (@ModFarm) - Facebook (@ModernFarmerMedia) - Instagram (@modfarm)

Use our content respectfully

Modern Farmer is a nonprofit and as such we share our content for free and in good faith in order to reach new audiences. Respectfully,

No selling ads against our stories. It’s okay to put our stories on pages with ads.
Don’t republish our material wholesale, or automatically; you need to select stories to be republished individually.
You have no rights to sell, license, syndicate, or otherwise represent yourself as the authorized owner of our material to any third parties. This means that you cannot actively publish or submit our work for syndication to third party platforms or apps like Apple News or Google News. We understand that publishers cannot fully control when certain third parties automatically summarize or crawl content from publishers’ own sites.

Keep in touch

We want to hear from you if you love Modern Farmer content, have a collaboration idea, or anything else to share. As a nonprofit outlet, we work in service of our community and are always open to comments, feedback, and ideas. Contact us at [email protected].

Food Waste, No More”Scientists Have Figured Out A New Use For Orange Peels

by Dan Nosowitz, Modern Farmer
March 25, 2017

					<h1>Food Waste, No More”Scientists Have Figured Out A New Use For Orange Peels</h1>
<p class="byline">by Dan Nosowitz, Modern Farmer <br />March 25, 2017</p>
					<p>A whopping 3.8 million tons of citrus peels go to waste each year. This is annoying for processors, who have to figure out some way to dispose of them, and disheartening for us as lovers of all weird ways to repurpose food waste.</p>
<p>But a group of Spanish researchers <a href="http://canal.ugr.es/noticia/wastewater-cleaned-thanks-to-new-adsorbent-material-made-from-fruit-peels/" target="_blank" rel="noopener">have come up with a new use</a> for this so-called waste: as a material in wastewater treatment facilities that can filter out bad metals and other pollutants. This first test was done with copper, a potentially toxic heavy metal present in some water.</p>
<p>These researchers have figured out a process to turn citrus peels - oranges and grapefruits were tested, though the process could in the future apply to other peels - into a sort of burnt-umber sediment by first dehydrating then, then chemically treating them to mess with the acid/base ratio and their texture. That enables the peels to filter out exactly the metals we don't want in our water, and to enhance their adsorption. (Not <em>absorption</em>, mind you: adsorption describes a filtering process, in which undesired materials can't make it through a material and instead form a sort of film on the outside.)</p>
<p>The final powdery product looks a bit like the carbon-based filter material you might find on the inside of a Brita filter, and for good reason: it has a similar effect.</p>
<p>Put into a wastewater treatment system, the peel-based material showed promise for filtering out nasty metals in water - enough so that the researchers believe it could actually compete with activated carbon (the stuff in your Brita filter). Here's a fun fact: the carbon in the Brita filter is made by <a href="https://www.brita.com/why-brita/what-we-filter/" target="_blank" rel="noopener">burning up coconut hulls</a>. Another nice use of food waste!</p>

					<p>This &lt;a target=&quot;_blank&quot; href=&quot;https://modernfarmer.com/2017/03/another-use-orange-peels-wastewater-pollutant-cleaner/&quot;&gt;article&lt;/a&gt; first appeared on &lt;a target=&quot;_blank&quot; href=&quot;https://modernfarmer.com&quot;&gt;Modern Farmer&lt;/a&gt; and is republished here under a Creative Commons license.&lt;img src=&quot;https://modernfarmer.com/wp-content/uploads/2024/08/cropped-favicon-1-150x150.png&quot; style=&quot;width:1em;height:1em;margin-left:10px;&quot;&gt;&lt;img id=&quot;republication-tracker-tool-source&quot; src=&quot;https://modernfarmer.com/?republication-pixel=true&amp;post=54199&quot; style=&quot;width:1px;height:1px;&quot;&gt;</p>

Modern Farmer Weekly

Solutions Hub

Innovations, ideas and inspiration. Actionable solutions for a resilient food system.

Explore

Explore other topics

Farm
Food
Consumption

Share With Us

We want to hear from Modern Farmer readers who have thoughtful commentary, actionable solutions, or helpful ideas to share.

Submit