scholarly journals Eco-friendly Chrome Tanning of Leather using Ultrasound Technique

2021 ◽  
Author(s):  
Md. Abu Sayid Mia ◽  
Shamima Yeasmin ◽  
Mohammad Nurnabi ◽  
Md. Zahangir Alam
Keyword(s):  
Cross Section ◽  
Conventional Method ◽  
Scanning Calorimetry ◽  
Ultrasound Technique ◽  
Environment Friendly ◽  
Shrinkage Temperature ◽  
Leather Processing ◽  
Chrome Tanning ◽  
Tanning Process ◽  
Sem Analyses

Abstract This article describes the development of an environment friendly chrome tanning of leather using ultrasound. Most of the leathers are tanned by the conventional method using basic chromium sulphate. It is one of the most polluting and time-consuming steps in leather processing. In this study, investigations were carried out on ultrasound assisted eco-friendly tanning process so that the chrome tanning agent could provide better quality leather without creating any environmental problem. Effects of using ultrasound in chrome tanning process were studied at different pH, tanning time, tanning agent dosage, and then compared with that of conventional method. Tanned leathers were characterized by scanning electron microscopy (SEM), photomicrographic analysis, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), energy dispersive X-ray (EDX), etc. SEM analyses of the surface and cross-section of the tanned leather showed that fibre structures were not affected by ultrasound. It was also found that the shrinkage temperature of leather tanned with ultrasound was increased by about 5–29°C. Chrome uptake and content were found to increase by 30–50% and 1–7%, respectively. Tanning time was shortened from 6 hours to 2 hours and the quantity of leachable chromium in the leather was also decreased significantly. The noteworthy enhancing effects have been attributed largely because of the increased penetration of tanning agents into pickled leather. Photomicrographic analysis of the cross-section of the tanned leather also showed a higher penetration of tanning agents in presence of ultrasound.

Eco-friendly Leather Dyeing using Ultrasound Technique

2020 ◽  
Vol 115 (6) ◽  
pp. 199-205
Author(s):  
Md. Abu Sayid Mia ◽  
Refat E Ashraf ◽  
Mohammad Nurnabi ◽  
Md. Zahnagir Alam
Keyword(s):  
Cross Section ◽  
Fiber Structure ◽  
Dye Uptake ◽  
Scanning Calorimetry ◽  
Mechanical Agitation ◽  
Ultrasound Technique ◽  
Dye Penetration ◽  
Spent Liquor ◽  
And Diffusion ◽  
Sem Analyses

In this study, leather was dyed using ultrasound and conventional methods to investigate the influence of ultrasound on leather dyeing. Ultrasound is more effective than mechanical agitation in enhancing leather dyeing. Effects of various process parameters, such as, dyeing temperature, dyeing time and doses of dye on dyeing of leather in presence of ultrasound were investigated. Dyed leathers were characterized with scanning electron microscopy (SEM), photomicrographic analysis, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), etc. It was observed that percentage exhaustion of dye, dye uptake, dye penetration and diffusion coefficient were increased significantly in presence of ultrasound compared to those of dyeing in absence of ultrasound. Moreover, physical properties of the dyed leathers were also investigated. Color rub fastness, perspiration, tensile strength, etc. of dyed leather in presence of ultrasound were higher than that of without ultrasound. SEM analyses of the surface and cross section of the dyed leather showed that fiber structure was not affected by ultrasound. Photomicrographic analysis of cross-section of the dyed leather also showed a deeper penetration of dye in presence of ultrasound. Consequently, dye content in the spent liquor was decreased resulting in a lower environmental pollution.

Role of Anionic Chromium Species in Leather Tanning

2021 ◽  
Vol 116 (10) ◽  
Author(s):  
Abhinandan Kumar ◽  
Jaya Prakash Alla ◽  
Deepika Arathanaikotti ◽  
Ashok Raj J. ◽  
Chandrababu N. K.
Keyword(s):  
Thermal Stability ◽  
Organic Acid ◽  
Organoleptic Properties ◽  
Chromium Species ◽  
Shrinkage Temperature ◽  
Leather Processing ◽  
Chrome Tanning ◽  
Anionic Species ◽  
Reactive Mechanism

Chrome tanned leathers are definitely unique in comparison with leather made from any other known tanning agents, especially in terms of thermal stability, cost and its reactive mechanism with collagen fibers. In our current studies, self basifying chrome tanning materials masked with different percentages of organic acid were prepared and applied after the de-liming stage of leather processing. This eliminated the need for pickling and basification steps. Tanned leathers resisted shrinkage up to 103 and 105±2°C while conventional chrome tanned leathers resisted up to 108±2°C. Also, interaction of anionic chrome species in tanning was studied. It was observed that the percentage of anionic species in the experimental chrome tanning material was higher than conventional chrome tanning material and the shrinkage temperature achieved by application of experimental tanning material proves that anionic species do involve in tanning. Tanned leathers were crusted and analysed for strength and organoleptic properties.

scholarly journals Pilot-Scale Study on Masking Agents for Titanium Tanning

2015 ◽  
Vol 1120-1121 ◽  
pp. 203-207
Author(s):  
Monica Puccini ◽  
Maurizia Seggiani ◽  
Christian Pomelli ◽  
Sandra Vitolo
Keyword(s):  
Pilot Scale ◽  
Titanyl Sulfate ◽  
Shrinkage Temperature ◽  
Chrome Tanning ◽  
Physical Testing ◽  
Tanning Process ◽  
Masking Agents ◽  
Temperature Scanning ◽  
The Many ◽  
Almost All

The many advantages offered by chrome tanning justify its widespread use for production of almost all types of leather. However, the traditional chromium (III) tanning process is constantly under threat from the pressure of legislation, and ever-tightening restrictions require to minimize chromium-containing effluents discharge and chromium-containing wastes production. Recently, the manufacture and use of chromium (III) free tanning agents compounds have been studied intensively. Among these, Titanium (IV)-based salts is one of the most promising substitutes.In this study, the use of titanyl sulfate as tanning agent for the production of high-quality bovine upper leather was investigated. In order to optimize the titanium tanning performances, a comparative evaluation, on pilot-scale, of citrate and lactate ions as masking agents was performed.The developed process has been validated through various analyses of the obtained crust leathers such as shrinkage temperature, scanning electron microscopy, and physical testing. The final leather obtained with the innovative method shows similar properties to those of the conventional tanned leather in terms of technical and mechanical properties.

scholarly journals Sustainable Chrome Tanning System Using Protein Based Product Developed from Leather Waste: Wealth from Waste

2021 ◽  
Author(s):  
James Kanagaraj ◽  
Rames Chandra Panda ◽  
Ramakrishnan Prasanna
Keyword(s):  
Active Sites ◽  
Control Sample ◽  
Strength Properties ◽  
Hydroxyl Groups ◽  
Experimental Sample ◽  
Shrinkage Temperature ◽  
Chrome Tanning ◽  
Tanning Process ◽  
Microscopic Studies ◽  
Enhanced Adsorption

Abstract Chrome tanning is one of the popular tanning methods followed globally that generates considerable level of chromium pollution in the resulting effluent. The existing conventional chrome tanning system has to be modified to increase the exhaustion level of chromium in the tanning process. In the present investigation, a protein based product has been developed from raw trimming wastes and applied in chrome tanning process to enhance the exhaustion level of chromium. The experiment conducted using the product at the level of 6% exhibited chromium exhaustion at the level of 93% in the process. FT-IR analysis revealed the presence of peaks for various functional groups namely carboxylic acids, aldehyde, amide and hydroxyl groups for the high exhaust chrome tanning. The shrinkage temperature of the experimental leather was found to be more than 100 o C. Results of microscopic studies from SEM-EDX revealed that enhanced adsorption of chromium up to a level of 5.24 weight % containing chromium with atomic % 1.27 in the sample of 6% co-polymer. AFM images also show increase in adsorption of chromium with increased amount of co-polymer in the solution. Increased interactions between active sites of collagen-complex and chromium resulted into improved exhaustion of chromium as revealed from higher intensities of XRD images. CD spectra revealed that the addition of protein based product increased the ellipticity of the collagen in the experimental sample as compared to control sample. The crust leather showed improved colour, organoleptic and comparable strength properties of the experimental leather.

scholarly journals Interactions between Collagen and Alternative Leather Tannages to Chromium Salts by Comparative Thermal Analysis Methods

2021 ◽  
Author(s):  
Ali Yorgancioglu ◽  
Ersin Onem ◽  
Onur Yilmaz ◽  
Huseyin Ata Karavana
Keyword(s):  
Thermal Analysis ◽  
Thermal Stabilization ◽  
Leather Industry ◽  
Scanning Calorimetry ◽  
Shrinkage Temperature ◽  
Conventional View ◽  
Analysis Methods ◽  
Tanning Process ◽  
Free Replacement ◽  
Vegetable Tanning

This study aims to investigate the interactions between collagen and tanning process performed by Ecoltan®, phosphonium, EasyWhite Tan®, glutaraldehyde, formaldehyde-free replacement syntan, condensed (mimosa) and hydrolyzed (tara) vegetable tanning agents as alternative tannages to conventional basic chromium sulphate widely used in leather industry. Collagen stabilization with tanning agents was determined by comparative thermal analysis methods; differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and conventional shrinkage temperature measurement. Analysis techniques and tanning agents were compared and bonding characteristics were commented by thermal stabilization they provided. Chromium tanning agent was also examined to be comparable of novel tannages for leather industry. The results were interesting as a different perspective than the conventional view to provide a better understanding of the relationship between tanning and thermal stability of leather materials.

scholarly journals Technology of Free Chrome Tanning Process: Optimal Level of Formaldehyde as Tanning Agent for Mondol Stingray (Himantura gerrardi)

2020 ◽  
Vol 20 (3) ◽  
pp. 277-286
Author(s):  
Laili Rachmawati ◽  
Emiliana Anggriyani ◽  
Nur Mutia Rosiati
Keyword(s):  
Tensile Strength ◽  
Optimal Level ◽  
Raw Material ◽  
Shrinkage Temperature ◽  
Tear Strength ◽  
Chrome Tanning ◽  
Tanning Process ◽  
High Level

Chrome (VI) has a high level of toxicity. Formaldehyde is potential to be developed as a substitute of chrome tanning agent. The aims of this study are to explain the amount of formaldehyde bound, shrinkage temperature, tensile strength, and tear strength on Mondol stingray (Himantura gerrardi) leather. Pickled mondol stingray has been used as raw material. The study was divided into 4 treatments, that is P.I (formaldehyde 2%), P.II (formaldehyde 4%), P.III (formaldehyde 6%), and P.IV (formaldehyde 8%). The method used is drum tanning. Shrinkage temperatures, tensile strength and tear strength of P.I and P.II are significantly different from P.III and P.IV, but P.I is not significantly different from P.II, whereas P.III is not significantly different from P.IV. P.III is shown to improve the quality of leather stingray more than P.I and P.II, and has fulfilled the requirements of leather stingray according to SNI. 06-6121-1999. It can be concluded that the optimal level of formaldehyde tanning agent that can be used as a chrome tanning agent substitute in tanning Mondol stingray skin is formaldehyde 8% (P.III).

scholarly journals Enzymes for Leather Processing: Effect on Pickling and Chroming

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1480
Author(s):  
Renata Biškauskaitė ◽  
Violeta Valeikienė ◽  
Virgilijus Valeika
Keyword(s):  
Mechanical Properties ◽  
Acidic Medium ◽  
Proteolytic Enzymes ◽  
Relative Elongation ◽  
The Other ◽  
Shrinkage Temperature ◽  
Processing Effect ◽  
Leather Processing ◽  
Production Processes ◽  
Pickling Process

Recently, increasing attention has been paid to the application of enzymes in a wide variety of leather production processes. The aim of the present study was to investigate the action of enzymatic pickling on derma’s collagen and the influence of this action on subsequent processes and properties of chromed and finished leather. The application of active in acidic medium proteolytic enzymes in the pickling process led to an additional impact on derma structure: collagen was more strongly affected and the porosity of the pelt dermis was reduced, but the hide became more thermally stable. The enzymatically pickled pelt bonded more chromium and reached higher shrinkage temperature while chroming; dyes penetrated deeper; such leather bonded more fatliquors. On the other hand, the action of enzymes worsened the physical–mechanical properties of the leather, as the experimental leather was weaker than the conventional one. The first was characterised by weaker grain layer and had significantly higher relative elongation. Therefore, as some properties improve and others worsen during such a process, the application of every enzyme should be carefully investigated and optimized to produce a leather with defined properties.

scholarly journals Graphene Oxide as a Nanocarrier for Controlled Loading and Targeted Delivery of Typhonium giganteum Drugs

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Xiaohua Gu ◽  
Rui Cao ◽  
Fu Li ◽  
Yan Li ◽  
Hongge Jia ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Graphene Oxide ◽  
Targeted Delivery ◽  
Drug Carrier ◽  
Dual Function ◽  
Natural Environments ◽  
Scanning Calorimetry ◽  
Environment Friendly ◽  
A549 Lung ◽  
Scanning Electron

In this study, Typhonium giganteum containing dual-function nanofibers composed of poly(butylene carbonate), polylactic acid, and graphene oxide (PBC/PLA/GO) were successfully fabricated by electrospinning. The results from thermogravimetric analysis (TG), differential scanning calorimetry (DSC), and Fourier-transform infrared spectroscopy (FTIR) indicate that no interactions occurred between PBC and PLA. The nanofiber microstructure upon which graphene oxide was evenly distributed was studied by scanning electron microscopy (SEM) and showed good silk properties. The nanofibers can be used as a drug carrier since loaded Typhonium giganteum fibers possess excellent biocompatibility. Such nanofibers are effective in inhibiting the proliferation of A549 lung cancer cells, and thus they have potential for replacing chemotherapy-based treatments of lung cancer. In addition, the PBC/PLA/GO nanofibers degrade in physiological and natural environments, which is an important feature when engineering tissues and environment-friendly materials.

scholarly journals Analysis of Chemical Composition Homogeneity in the Cross-section of the Rods Produced from Alloys of 6xxx Group

2020 ◽  
Vol 66 (3) ◽  
pp. 139-148
Author(s):  
Maja Vončina ◽  
Peter Cvahte ◽  
Ana Kračun ◽  
Tilen Balaško ◽  
Jožef Medved
Keyword(s):  
Corrosion Resistance ◽  
Chemical Composition ◽  
Cross Section ◽  
Cross Sections ◽  
Intermetallic Phases ◽  
Scanning Calorimetry ◽  
Good Corrosion Resistance ◽  
Energy Dispersion Spectrometer ◽  
High Casting Speed ◽  
The Cross

AbstractThe alloys from Al–Mg–Si system provide an excellent combination of mechanical properties, heat treatment at extrusion temperature, good weldability, good corrosion resistance and formability. Owing to the high casting speed of rods or slabs, the solidification is rather non-equilibrium, resulting in defects in the material, such as crystalline segregations, the formation of low-melting eutectics, the unfavourable shape of intermetallic phases and the non-homogeneously distributed alloying elements in the cross-section of the rods or slabs and in the entire microstructure. The inhomogeneity of the chemical composition and the solid solution negatively affects the strength, the formability in the warm and the corrosion resistance, and can lead to the formation of undesired phases due to segregation in the material. In this experimental investigation, the cross-sections of the rods from two different alloys of the 6xxx group were investigated. From the cross-sections of the rods, samples for differential scanning calorimetry (DSC) at three different positions (edge, D/4 and middle) were taken to determine the influence of inhomogeneity on the course of DSC curve. Metallographic sample preparation was used for microstructure analysis, whereas the actual chemical composition was analysed using a scanning electron microscope (SEM) and an energy dispersion spectrometer (EDS).

A comparative study on the effect of higher acrylate on cross-linkable PMMA used as environment friendly latexes

2020 ◽  
Vol 32 (2) ◽  
pp. 135-141
Author(s):  
Sweta Shukla
Keyword(s):  
Thermal Analysis ◽  
Differential Scanning Calorimetry ◽  
Butyl Methacrylate ◽  
Cross Linking ◽  
Scanning Calorimetry ◽  
Environment Friendly ◽  
Glycol Diacrylate ◽  
Poly Propylene ◽  
Kinetics Of ◽  
Scanning Electron

The kinetics of emulsion polymerization of monomers methyl methacrylate (MMA)/ n-butyl methacrylate (BMA) was studied to investigate the effect of cross-linkable monomer poly(propylene glycol diacrylate) (PPGDA). The results showed that by the incorporation of PPGDA rate constant of reaction decreased. Fourier transform infrared spectroscopy and scanning electron microscope were used to characterize the synthesized polymers. The thermal analysis of samples was done by differential scanning calorimetry, and the results were compared by the previous studies with MMA/ n-butyl acrylate (BA) and MMA/2-ethylhexyl acrylate (EHA). The glass transition temperature ( T g) values show that the latexes prepared using BA and EHA as comonomer was suitable for binder purpose, but in the present study the T g is not suitable in case of BMA as higher acrylate comonomer. That may be due to more cross-linking in MMA-BMA-PPGDA. The results conclude that the BA and EHA can be used as the binder, but the use of BMA is limited for the binder in coating applications.

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