Traditional chrome tanning technology is still widely used today. In this technology, chrome shaving as well as chrome contained effluent in tanning and retanning processes is a big issue in the industry. Wet white ta...Traditional chrome tanning technology is still widely used today. In this technology, chrome shaving as well as chrome contained effluent in tanning and retanning processes is a big issue in the industry. Wet white tanning technology has been gaining in importance in recent years, but in general, the comprehensive performance of chrome-free tanned leather is not comparable with that of chrome tanned leather. In the present work, chrome-free tanning and chrome tanning are combined in a reversed procedure, which produces leather with chrome tanned leather quality without chrome tanned leather waste problems. In this procedure, a special amphoteric organic compound, no pickle, no salt chrome-free tanning agent TWT was used to tan delimed hides （no pickle） making wet white with shrinking temperature at 80-85 ~C. Then, new method called reversed tanning further process the wet white into chrome-tanned crust. In this reversed method, retanning, fatliquoring and coloring processes were carried out before chrome tanning. This technology eliminates chrome waste issue in tanning, shaving, post tanning processes. The chrome contained effluent is only concentrated in the last chrome tanning process. The leather made with this technology has complete conventional chrome-tanned leather quality. In this way, chrome leather quality without chrome waste problems was achieved. So, it is a new clean tanning technology.展开更多
Green solvents,such as propylene carbonate(PC),can be used in leather processing to improve the efficiency of chrome tanning and reduce wastewater.Here we report a combined small-angle X-ray scattering(SAXS)and differ...Green solvents,such as propylene carbonate(PC),can be used in leather processing to improve the efficiency of chrome tanning and reduce wastewater.Here we report a combined small-angle X-ray scattering(SAXS)and differential scanning calorimetry(DSC)study on PC and its efficacy as a carrier medium during chrome tanning.SAXS analysis on the collagen structure of chrome tanned leather using PC,compared to conventionally tanned leather using water,showed an increase in Cr uptake in addition to the more uniform penetration of Cr through the leather cross-section.The increased binding of Cr to the collagen matrix drives the decreased hydration environment of the collagen triple helix.Furthermore,DSC studies show a uniform hydrothermal stability for the PC samples due to the more even distribution of Cr through the collagen matrix.Understanding the mechanisms by which chrome tanning occurs in non-aqueous solvents can guide us towards a more sustainable future for the leather industry.展开更多
文摘Traditional chrome tanning technology is still widely used today. In this technology, chrome shaving as well as chrome contained effluent in tanning and retanning processes is a big issue in the industry. Wet white tanning technology has been gaining in importance in recent years, but in general, the comprehensive performance of chrome-free tanned leather is not comparable with that of chrome tanned leather. In the present work, chrome-free tanning and chrome tanning are combined in a reversed procedure, which produces leather with chrome tanned leather quality without chrome tanned leather waste problems. In this procedure, a special amphoteric organic compound, no pickle, no salt chrome-free tanning agent TWT was used to tan delimed hides （no pickle） making wet white with shrinking temperature at 80-85 ~C. Then, new method called reversed tanning further process the wet white into chrome-tanned crust. In this reversed method, retanning, fatliquoring and coloring processes were carried out before chrome tanning. This technology eliminates chrome waste issue in tanning, shaving, post tanning processes. The chrome contained effluent is only concentrated in the last chrome tanning process. The leather made with this technology has complete conventional chrome-tanned leather quality. In this way, chrome leather quality without chrome waste problems was achieved. So, it is a new clean tanning technology.
基金funded by the Ministry of Business,Innovation and Employment(MBIE)through grant LSRX-1801funded by the Ministry of Science and Technology Taiwan(MOST).
文摘Green solvents,such as propylene carbonate(PC),can be used in leather processing to improve the efficiency of chrome tanning and reduce wastewater.Here we report a combined small-angle X-ray scattering(SAXS)and differential scanning calorimetry(DSC)study on PC and its efficacy as a carrier medium during chrome tanning.SAXS analysis on the collagen structure of chrome tanned leather using PC,compared to conventionally tanned leather using water,showed an increase in Cr uptake in addition to the more uniform penetration of Cr through the leather cross-section.The increased binding of Cr to the collagen matrix drives the decreased hydration environment of the collagen triple helix.Furthermore,DSC studies show a uniform hydrothermal stability for the PC samples due to the more even distribution of Cr through the collagen matrix.Understanding the mechanisms by which chrome tanning occurs in non-aqueous solvents can guide us towards a more sustainable future for the leather industry.
