大麻碱氧一浴一步法短流程脱胶漂白新工艺研究
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摘要
大麻纤维是未来最有前途的纤维素纤维，大麻纤维的形态与化学组分使大麻纤维、大麻纺织品具有良好的抗菌抑菌、吸湿透气，屏蔽辐射、润肤爽身等天然保健功能。并且大麻具有生态安全生产和最终产品可抛性，是真正的“绿色产品”，可开发多种环保型的纺织和非纺织制品。
综观目前的大麻脱胶法，主要有自然发酵法脱胶、化学脱胶和生物脱胶。自然发酵法受环境影响大，时间长，杂菌多，质量难以保证；目前国内外大麻的化学脱胶基本沿用苎麻脱胶工艺，采用煮漂二步或者两步以上的工艺流程，工艺流程长，成本高，消耗大；生物脱胶虽然能耗低，对环境的污染少，但存在脱胶不彻底的缺点，最终还要辅以化学脱胶。为此，本文对大麻进行碱氧一浴一步法短流程脱胶漂白新工艺研究，把常规的碱煮和漂白两步工序缩短为一步，既将煮漂两步工序各自的去除对象，合并在一步完成。所研究的主要内容有：
1．借鉴现有的其他麻类化学脱胶漂白工艺研究的成果，确定大麻碱氧一浴一步法短流程脱胶漂白新工艺的工艺流程。
2．对新工艺的工艺参数：碱氧一浴化学用剂NaOH、双氧水和处理时间进行初步优化实验，确定出最佳工艺参数的大体范围。
3．利用二次通用旋转组合设计研究主要工艺参数和脱胶效果及精干麻品质指标之间的关系，确定最优工艺方案。
4．对碱氧一浴中化学用剂如NaOH、H_2O_2等对大麻原麻中各主要成分如纤维素、半纤维素及木质素、果胶等的作用原理进行分析，并对碱氧一浴的应用原理在理论上进行初步探讨与分析。
通过实验分析，得到如下的主要结论：
1．大麻原麻利用碱氧一浴一步法脱胶漂白的新工艺，不但可以缩短脱胶时间和操作工序，达到了预期的“短流程”目的，而且脱胶效果也非常明显，并有提高大麻可纺性及最终产品质量的潜力。
2．双氧水用量、NaOH浓度和处理时间对大麻精干麻残胶率的大小均有明显的影响。
3．双氧水用量对大麻木质素的去除有显著影响，即对于木质素的去除效果起主要作用；而NaOH浓度、处理时间对木质素的去除的影响与双氧水的用量相比并不是非常显著，两者处于次要地位，尤其是处理时间，对木质素的去除效果最不明显。
4．双氧水用量在9.5～10g／l，NaOH浓度10～11g／l，预处理时间在120～130min时，大麻精干麻的脱胶效果相对最好。
The hemp fiber is the most prospective cellulosic fibre. It has many natural healthcare functions such as good bacterial repellency & inhibition, good absorption-air permeability, shielding radiation, it is emollient, frash and comfortable. What's more, hemp has the ecology-safe-productivity and end-product-recycling, it is the real "green product", many environmental protective textile and non-textile products can be developed from hemp fiber.
To make a comprehensive survey, there are three methods for the hemp dugumming: natural fermentation, chemical dugumming and biological degumming. The natural fermentation has many disadvantages such as long processing time, much dependence on the circumstance and having not enough quality assurance; chemical degumming often uses methods of ramie degumming, namely the processes of degumming and bleaching in two steps or more, which has the disadvantages of long process and long treatment time, high cost and consumption; though the biological degumming has little energy consumption, the degumming is incomplete, it need secondary chemical degumming. So new shorten process of one-bath alkali-H2O2 of degumming & bleaching is studied in this paper, the two steps of degumming and bleaching are shortened in one step, which has high efficiency and low consumption. The paper mainly deals with the following:
a) On the basis of studying some chemical degumming processes of other bast fibres, a new shorten process of degumming & bleaching in one step will be given.
b) A series of tentative optimized experiments are carried out to get the best range of the three parameters: the concentrations of NaOH and H2O2, the treatment time.
c) Using the universal rotatable experimental design to obtain the regression equation with high precision and the relations between the main parameters (NaOH and H2O2 concentration and treatment time and the efficiency of cooking off gum and lignin; finding the best degumming technique.
d) Analyzing the reaction principles between the reagents such as NaOH and H2O2 and the components of the bast of hemp such as cellulose, semi-cellulose, lignin and pectin, and some tentative experiments are carried out about the principle of alkali and hydrogen peroxide in one bath.
After the above researches and experiments, the conclusions could be obtained as follows:
1. The new process can not only shorten the degumming time and steps that has achieved the expected "shorten process", but also has an apparent influence to the degumming and can increase spinnability of hemp fiber.
2. The three parameters: NaOH and H2O2 concentration and treatment time all apparently affect the percent of gum content in degummed hemp.
3. H2O2 density has the apparent influence to the percent of residual lignin in degummed hemp, namely, it mainly affects the content of residual lignin; the influence of NaOH concentration and treatment time are not so obvious to the residual lignin comparatively, especially for the treatment time, it has little influence.
4. The best combination of those parameters for the degumming and bleaching of hemp is: H2O2 9.5-10g/1, NaOH 10-11lg/1, treatment time 120-130min.
综观目前的大麻脱胶法，主要有自然发酵法脱胶、化学脱胶和生物脱胶。自然发酵法受环境影响大，时间长，杂菌多，质量难以保证；目前国内外大麻的化学脱胶基本沿用苎麻脱胶工艺，采用煮漂二步或者两步以上的工艺流程，工艺流程长，成本高，消耗大；生物脱胶虽然能耗低，对环境的污染少，但存在脱胶不彻底的缺点，最终还要辅以化学脱胶。为此，本文对大麻进行碱氧一浴一步法短流程脱胶漂白新工艺研究，把常规的碱煮和漂白两步工序缩短为一步，既将煮漂两步工序各自的去除对象，合并在一步完成。所研究的主要内容有：
1．借鉴现有的其他麻类化学脱胶漂白工艺研究的成果，确定大麻碱氧一浴一步法短流程脱胶漂白新工艺的工艺流程。
2．对新工艺的工艺参数：碱氧一浴化学用剂NaOH、双氧水和处理时间进行初步优化实验，确定出最佳工艺参数的大体范围。
3．利用二次通用旋转组合设计研究主要工艺参数和脱胶效果及精干麻品质指标之间的关系，确定最优工艺方案。
4．对碱氧一浴中化学用剂如NaOH、H_2O_2等对大麻原麻中各主要成分如纤维素、半纤维素及木质素、果胶等的作用原理进行分析，并对碱氧一浴的应用原理在理论上进行初步探讨与分析。
通过实验分析，得到如下的主要结论：
1．大麻原麻利用碱氧一浴一步法脱胶漂白的新工艺，不但可以缩短脱胶时间和操作工序，达到了预期的“短流程”目的，而且脱胶效果也非常明显，并有提高大麻可纺性及最终产品质量的潜力。
2．双氧水用量、NaOH浓度和处理时间对大麻精干麻残胶率的大小均有明显的影响。
3．双氧水用量对大麻木质素的去除有显著影响，即对于木质素的去除效果起主要作用；而NaOH浓度、处理时间对木质素的去除的影响与双氧水的用量相比并不是非常显著，两者处于次要地位，尤其是处理时间，对木质素的去除效果最不明显。
4．双氧水用量在9.5～10g／l，NaOH浓度10～11g／l，预处理时间在120～130min时，大麻精干麻的脱胶效果相对最好。
The hemp fiber is the most prospective cellulosic fibre. It has many natural healthcare functions such as good bacterial repellency & inhibition, good absorption-air permeability, shielding radiation, it is emollient, frash and comfortable. What's more, hemp has the ecology-safe-productivity and end-product-recycling, it is the real "green product", many environmental protective textile and non-textile products can be developed from hemp fiber.
To make a comprehensive survey, there are three methods for the hemp dugumming: natural fermentation, chemical dugumming and biological degumming. The natural fermentation has many disadvantages such as long processing time, much dependence on the circumstance and having not enough quality assurance; chemical degumming often uses methods of ramie degumming, namely the processes of degumming and bleaching in two steps or more, which has the disadvantages of long process and long treatment time, high cost and consumption; though the biological degumming has little energy consumption, the degumming is incomplete, it need secondary chemical degumming. So new shorten process of one-bath alkali-H2O2 of degumming & bleaching is studied in this paper, the two steps of degumming and bleaching are shortened in one step, which has high efficiency and low consumption. The paper mainly deals with the following:
a) On the basis of studying some chemical degumming processes of other bast fibres, a new shorten process of degumming & bleaching in one step will be given.
b) A series of tentative optimized experiments are carried out to get the best range of the three parameters: the concentrations of NaOH and H2O2, the treatment time.
c) Using the universal rotatable experimental design to obtain the regression equation with high precision and the relations between the main parameters (NaOH and H2O2 concentration and treatment time and the efficiency of cooking off gum and lignin; finding the best degumming technique.
d) Analyzing the reaction principles between the reagents such as NaOH and H2O2 and the components of the bast of hemp such as cellulose, semi-cellulose, lignin and pectin, and some tentative experiments are carried out about the principle of alkali and hydrogen peroxide in one bath.
After the above researches and experiments, the conclusions could be obtained as follows:
1. The new process can not only shorten the degumming time and steps that has achieved the expected "shorten process", but also has an apparent influence to the degumming and can increase spinnability of hemp fiber.
2. The three parameters: NaOH and H2O2 concentration and treatment time all apparently affect the percent of gum content in degummed hemp.
3. H2O2 density has the apparent influence to the percent of residual lignin in degummed hemp, namely, it mainly affects the content of residual lignin; the influence of NaOH concentration and treatment time are not so obvious to the residual lignin comparatively, especially for the treatment time, it has little influence.
4. The best combination of those parameters for the degumming and bleaching of hemp is: H2O2 9.5-10g/1, NaOH 10-11lg/1, treatment time 120-130min.
引文
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[4]．N．P．Ingle等．张予涛译．大麻：未来最有前途的纤维素纤维．国外纺织技术，2001，1
[5]．王德骥等．苎麻碱煮化学脱胶机理研究．麻纺织技术，1999，No．5、6，2～7
[6]．冷鹃．用EDTA、生物酶对黄麻进行处理的研究．麻纺织技术，1997，No．4，34～37
[7]．邬义明．植物纤维化学．中国轻工业出版社，2000，3
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[17]．刘正初等．苎麻生物脱胶新技术工业化生产应用研究．纺织学报，2001，No．2，27～29
[18]．王测生．苎麻生物脱胶技术的创新．四川纺织科技，2001，No．1，4～6
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[2]．周明倞．大麻及其抗菌纺织品．麻纺织技术，1998，No．3，45～48
[3]．孙小寅，管映亭，温贵清等．大麻纤维的性能及其应用研究．纺织学报，2001，8，34～36
[4]．N．P．Ingle等．张予涛译．大麻：未来最有前途的纤维素纤维．国外纺织技术，2001，1
[5]．王德骥等．苎麻碱煮化学脱胶机理研究．麻纺织技术，1999，No．5、6，2～7
[6]．冷鹃．用EDTA、生物酶对黄麻进行处理的研究．麻纺织技术，1997，No．4，34～37
[7]．邬义明．植物纤维化学．中国轻工业出版社，2000，3
[8]．王菊生，孙铠．染整工艺原理．纺织工业出版社，1984
[9]．茆诗松等．回归分析及其实验设计．华东师范大学出版社，1981
[10]．徐谷仓．染整短流程前处理工艺、助剂和设备展望．纺织导报，2001，(5)
[11]．刘晓霞．苎麻脱胶快速预氧处理工艺．麻纺织技术，1997，No．4，7～9
[12]．刘晓霞，苎麻预氯处理时精干麻脱胶效果与工艺参数的关系．麻纺织技术，1998，No．3，26～29
[13]．杨红穗，张元明．大麻快速化学脱胶工艺初探．中国纺织大学学报，1999，No．5，83～86
[14]．王德骥．尿氧浸泡苎麻的新型脱胶工艺研究．纺织学报，1997，No．3，34～37
[15]．廖锋．对麻类产品市场发展趋势的分析．麻纺织技术．1997，No．6，6～9
[16]．孙小寅，王惠民．苎麻无浸酸常压碱煮脱胶工艺．麻纺织技术，1999，No．2，18～29
[17]．刘正初等．苎麻生物脱胶新技术工业化生产应用研究．纺织学报，2001，No．2，27～29
[18]．王测生．苎麻生物脱胶技术的创新．四川纺织科技，2001，No．1，4～6
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