Chromium recovery from chrome shaving generated in tanning process

2006 ◽  
Vol 129 (1-3) ◽  
pp. 143-146 ◽  
Author(s):  
M ERDEM
2017 ◽  
Vol 142 ◽  
pp. 2752-2760 ◽  
Author(s):  
Hongrui Ma ◽  
Jianjun Zhou ◽  
Li Hua ◽  
Fengxia Cheng ◽  
Lixiang Zhou ◽  
...  

1995 ◽  
Vol 31 (9) ◽  
pp. 73-81 ◽  
Author(s):  
Thongchai Panswad ◽  
Orathai Chavalparit ◽  
Yaowanud Sucharittham ◽  
Sasithorn Charoenwisedsin

In order to recover chromium, wastewaters from the chrome-tanning process in two Thai tanneries were coagulated with magnesium oxide or sodium carbonate at various dosages. Different types of polymer were also tried to improve the settleability of the chromium sludge which, in turn, was redissolved by sulfuric acid. The produced chromium III sulfate (Cr2(SO4)3) solution was sufficiently concentrated for direct reuse in the tanning step. The settling pattern of the chromium sludge was also observed and optimum sedimentation periods ranging from 1 to 17 hours were suggested. Under no tanning-additive (a chemical to improve chromium sorption onto hides) circumstances, the discharged wastewater contained 5-11 g Cr2O3/l and the most promising coagulant was MgO at a dose of twice the stoichiometric value and an optimum pH of 7-8. The resulting chromium precipitate or sludge was quite dense (21% solids) and possessed a good settling velocity (234 mm/h), making the decantation process very easy, whereas the corresponding acid requirement for the dissolution process was 1.5 times the stoichiometric value. On the other hand, in the tanning-additive situation, the chromium concentration in the drain was reduced to 3-6 g Cr2O3/l. Magnesium oxide was shown to be also the best coagulant but the dose was two times higher than that of the first circumstance, ie., four times that of stoichiometric requirement.


2021 ◽  
Vol 89 ◽  
pp. 106597
Author(s):  
Éverton Hansen ◽  
Patrice Monteiro de Aquim ◽  
Mariliz Gutterres

2020 ◽  
Vol 27 (33) ◽  
pp. 41437-41445
Author(s):  
Chao Zhu ◽  
Huiqin Wang ◽  
Hongrui Ma ◽  
Yonglin Yang ◽  
Fan Li
Keyword(s):  

Author(s):  
Bindia Sahu ◽  
Jaya Prakash Alla ◽  
Gladstone Christopher Jayakumar

Leather tanning is a stabilisation process of skin fibers. This is achieved by the interaction of collagen amino acids with tanning agents to stabilise skin from putrefaction. Tanning of collagen with oil is a special class of tanning known as chamois tanning. Chemically, the oil tanning involves oxidation of unsaturation present in the oil, which is generally achieved by exposing oil treated skins to air. In this study, Benzoyl peroxide has been used as an accelerating agent for oxidation of unsaturated bonds present in the linseed oil for oil tanning process. Results shows remarkable reduction in tanning duration from fifteen days to two days. The chamois leathers prepared using oxidation accelerant (Benzoyl peroxide) have been evaluated for physical properties such as water absorption (611%), tensile strength (18 N/mm2) and percentage of elongation (66 %) which are found to be better than control leathers.


2020 ◽  
Vol 115 (11) ◽  
pp. 409-412
Author(s):  
Ricardo Tournier

For over 100 years of tanning research, it is still arguable whether tanning chemicals weaken, strengthen or have an effect on the skin's original collagen fibers. The current paper is a review of the literature regarding the impact of the tanning process on the mechanical properties of leather specifically, tensile and tear strength, that raises several questions about this topic. A call is made for the scientific and technical community to address these questions


2005 ◽  
Vol 13 (7) ◽  
pp. 699-703 ◽  
Author(s):  
V. Sivakumar ◽  
V. John Sundar ◽  
T. Rangasamy ◽  
C. Muralidharan ◽  
G. Swaminathan

2020 ◽  
Author(s):  
Mihret Hailemariam Tekalign ◽  
Tolera Seda Badessa ◽  
Shegaw Ahmed Mohammed

Abstract The use of natural materials that is eco-friendly on leather as vegetable tannins has become a matter of significant importance, as a result of increased environmental awareness to prevent some hazardous synthetic tannin. Therefore, this study investigated that the potential of the extracted tannin from Sodom apple (Solanum Incanum) fruit for its effectiveness as vegetable tanning agent on goatskins. It was extracted with distilled water, methanol, petroleum ether and ethanol by using Soxhlet extraction method. Although the amount of material extracted was significant in all extracting solvents, water was a more efficient solvent (extraction yield of 16.71%) than the others. The qualitative analysis and structural characterization of the extracts were done using thin layer chromatography (TLC), Ultraviolet (UV) spectrometer and Fourier Transformer Infrared (FT-IR) spectrometer. The analysis confirmed that the presence of condensed tannins in the extract, which usually used for the application of tanning process in leather manufacturing industry. On other hand, the Quantitative Analysis of Sodom apple fruit extract was conducted by evaluating its moisture content (7.59%), total soluble solids (21.45%), tannin content (12.13%) and non-tannin contents (9.32%). The Scanning Electron Microscope (SEM) was carried out to study the effect of the tannin system on the structural and morphological characteristics of the tanned leathers. Similarly, the organoleptic and strength properties of the tanned leathers were evaluated in comparison with the control ones. Finally, the pollution loads of tanning liquors in Sodom apple tanning significantly reduced as compared with the control (mimosa). Thus, the results in this study showed that the manufacture of leather based on Sodom apple fruit extract found to be a cleaner alterative and promising pathway for tanning goatskins.


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