Zeology & sustainability

Zeology was developed to provide a sustainable alternative to existing tanning agents. Introducing Zeology is another step towards a more sustainable leather value chain. You can find more detailed information in the University of Zeology.

Cleaner waste streams

The charge of Zeology is negatively charged. This means that after the Zeology has bound to the leather protein it makes the leather have a character that allows dye, fat, and retanning at lower pH levels than a tanner would normally expect (it lowers the iso-electric point). This has great benefits to process time and chemicals used e.g. by good fixation of the wet-end chemicals. Through this improved fixation less chemicals end up in the waste streams of the tannery. Cleaner waste streams require less energy to process them.

Tannery waste stream processing

Liquid waste streams (e.g. floats) from the tannery are processed as those from traditional tanning processes. The sludge stream can be treated so that it meets the right conditions to be biodegradable. The solid waste streams mainly contain zeolite, as well as the natural collagen. Therefore, these waste streams are typically chrome, glutardialdehyde (GDA), and heavy metal-free, white of color and easy to handle. The waste streams coming from Zeology tanned leather are ready to be re-used, recycled or biodegraded in a potentially circular fashion.

Biodegradable waste streams

Zeology tanned collagen, Zeo White, may form the basis of biodegradable leather when combined with the biodegradable Wet-End & Finishing materials. Waste streams from zeolite tanned material (e.g. shavings, cuttings, clippings) and all sludge coming from the machines are relatively environmental friendly and will be biodegraded within reasonable times. Zeo White tanned materials are easily biodegradable (ISO method 20136:2017, hence similar conditions to waste water effluent treatments), up to 75% after 20 days. Chrome and glutardialdehyde (GDA) tanned materials reach ~5,0% and ~20%. After biodegrading the elements return to the environment and be used in a new cycle. Nera is currently investigating the possibilities of this feature and will share its outcome via this website and other channels.

Environmental impact

Zeology’s main benefit is for the environment: less pollution, less discharge of chemicals in waste and waste water, no use of chromium or glutardialdehyde (GDA), and improved biodegradability of the tanned material. Moreover, it offers superior leather performance to other chrome-free alternatives. Learn more at the University of Zeology.