The use of vegetable tanning materials in leather processing has drawn attention as an alternative to basic chromium sulphate for its natural abundance and environmental aspects.In this work,an attempt has been made t...The use of vegetable tanning materials in leather processing has drawn attention as an alternative to basic chromium sulphate for its natural abundance and environmental aspects.In this work,an attempt has been made to extract vegetable tannins from Xylocarpus granatum bark using different solvents(e.g.,water,methanol,ethanol,and chloroform)and compare with conventional vegetable tanning agents such as mimosa and quebracho.The highest extraction efficiency was observed 31.22%by methanol.The presence of tannin content and polyphenolic compounds,e.g.(-)epicatechin(503 mg/100 g dry extract),catechin hydrate(218 mg/100 g dry extract),catechol(29 mg/100 g dry extract)were ensured by UV-Vis,FT-IR spectroscopy and HPLC.Again,condensed tannins,moisture content,and pH of the methanol extracted tannin were found 47.80%,5.82%,and 3.97 respectively.The leather tanned by Xylocarpus granatum tannin showed a shrinkage temperature of 86.34±1.52℃.Other properties such as tensile strength,tear strength,grain cracking load,and distention at grain cracking were comparable to conventional vegetable-tanned leather.The cross-sectional morphology of the tanned leathers was also characterized by scanning electron microscopy(SEM)which revealed a compact structure of the leather fibers.In light of the findings from the study,X.granatum bark tannin could be a well alternative to chromium and a new source of vegetable tannin for the leather industry.展开更多
The use of vegetable tanning materials in leather processing has drawn attention as an alternative to basic chromium sulphate for its natural abundance and environmental aspects. In this work, an attempt has been made...The use of vegetable tanning materials in leather processing has drawn attention as an alternative to basic chromium sulphate for its natural abundance and environmental aspects. In this work, an attempt has been made to extract veg-etable tannins from Xylocarpus granatum bark using different solvents (e.g., water, methanol, ethanol, and chloroform) and compare with conventional vegetable tanning agents such as mimosa and quebracho. The highest extraction efficiency was observed 31.22% by methanol. The presence of tannin content and polyphenolic compounds, e.g. (-)epicatechin (503 mg/100 g dry extract), catechin hydrate (218 mg/100 g dry extract), catechol (29 mg/100 g dry extract) were ensured by UV-Vis, FT-IR spectroscopy and HPLC. Again, condensed tannins, moisture content, and pH of the methanol extracted tannin were found 47.80%, 5.82%, and 3.97 respectively. The leather tanned by Xylocar-pus granatum tannin showed a shrinkage temperature of 86.34 ± 1.52 °C. Other properties such as tensile strength, tear strength, grain cracking load, and distention at grain cracking were comparable to conventional vegetable- tanned leather. The cross-sectional morphology of the tanned leathers was also characterized by scanning electron microscopy (SEM) which revealed a compact structure of the leather fibers. In light of the findings from the study, X. granatum bark tannin could be a well alternative to chromium and a new source of vegetable tannin for the leather industry.展开更多
传统兔皮鞣制常常采用铬鞣剂及其他有机合成鞣剂,鞣制后会产生六价铬和游离甲醛,废液也难以处理。本试验采用新型生态有机鞣剂FTA鞣制兔皮,与皮胶原交联过程中仅产生中性盐和水,几乎不含游离甲醛。试验中对生态有机鞣剂FTA的主鞣工艺和...传统兔皮鞣制常常采用铬鞣剂及其他有机合成鞣剂,鞣制后会产生六价铬和游离甲醛,废液也难以处理。本试验采用新型生态有机鞣剂FTA鞣制兔皮,与皮胶原交联过程中仅产生中性盐和水,几乎不含游离甲醛。试验中对生态有机鞣剂FTA的主鞣工艺和不浸酸鞣制进行探索,最终确定最佳鞣制工艺条件为鞣剂用量8 g/L,温度35℃,鞣制时间为4 h后提碱至p H 8.0左右。鞣后兔皮的物理机械性能较强,毛被洁白、柔顺。展开更多
基金funded by the Ministry of Science and Technology,Bangladesh by the National Science and Technology(NST)fellowship(Group:Physical Science,Reg.No:317).
文摘The use of vegetable tanning materials in leather processing has drawn attention as an alternative to basic chromium sulphate for its natural abundance and environmental aspects.In this work,an attempt has been made to extract vegetable tannins from Xylocarpus granatum bark using different solvents(e.g.,water,methanol,ethanol,and chloroform)and compare with conventional vegetable tanning agents such as mimosa and quebracho.The highest extraction efficiency was observed 31.22%by methanol.The presence of tannin content and polyphenolic compounds,e.g.(-)epicatechin(503 mg/100 g dry extract),catechin hydrate(218 mg/100 g dry extract),catechol(29 mg/100 g dry extract)were ensured by UV-Vis,FT-IR spectroscopy and HPLC.Again,condensed tannins,moisture content,and pH of the methanol extracted tannin were found 47.80%,5.82%,and 3.97 respectively.The leather tanned by Xylocarpus granatum tannin showed a shrinkage temperature of 86.34±1.52℃.Other properties such as tensile strength,tear strength,grain cracking load,and distention at grain cracking were comparable to conventional vegetable-tanned leather.The cross-sectional morphology of the tanned leathers was also characterized by scanning electron microscopy(SEM)which revealed a compact structure of the leather fibers.In light of the findings from the study,X.granatum bark tannin could be a well alternative to chromium and a new source of vegetable tannin for the leather industry.
基金the Ministry of Science and Technology,Bangladesh by the National Science and Technology(NST)fellowship(Group:Physical Science,Reg.No:317).
文摘The use of vegetable tanning materials in leather processing has drawn attention as an alternative to basic chromium sulphate for its natural abundance and environmental aspects. In this work, an attempt has been made to extract veg-etable tannins from Xylocarpus granatum bark using different solvents (e.g., water, methanol, ethanol, and chloroform) and compare with conventional vegetable tanning agents such as mimosa and quebracho. The highest extraction efficiency was observed 31.22% by methanol. The presence of tannin content and polyphenolic compounds, e.g. (-)epicatechin (503 mg/100 g dry extract), catechin hydrate (218 mg/100 g dry extract), catechol (29 mg/100 g dry extract) were ensured by UV-Vis, FT-IR spectroscopy and HPLC. Again, condensed tannins, moisture content, and pH of the methanol extracted tannin were found 47.80%, 5.82%, and 3.97 respectively. The leather tanned by Xylocar-pus granatum tannin showed a shrinkage temperature of 86.34 ± 1.52 °C. Other properties such as tensile strength, tear strength, grain cracking load, and distention at grain cracking were comparable to conventional vegetable- tanned leather. The cross-sectional morphology of the tanned leathers was also characterized by scanning electron microscopy (SEM) which revealed a compact structure of the leather fibers. In light of the findings from the study, X. granatum bark tannin could be a well alternative to chromium and a new source of vegetable tannin for the leather industry.
文摘传统兔皮鞣制常常采用铬鞣剂及其他有机合成鞣剂,鞣制后会产生六价铬和游离甲醛,废液也难以处理。本试验采用新型生态有机鞣剂FTA鞣制兔皮,与皮胶原交联过程中仅产生中性盐和水,几乎不含游离甲醛。试验中对生态有机鞣剂FTA的主鞣工艺和不浸酸鞣制进行探索,最终确定最佳鞣制工艺条件为鞣剂用量8 g/L,温度35℃,鞣制时间为4 h后提碱至p H 8.0左右。鞣后兔皮的物理机械性能较强,毛被洁白、柔顺。
