阅读说明：本技术 一种超声波辅助臭氧处理改善高得率竹浆纤维柔软度的方法 (Method for improving softness of high-yield bamboo pulp fibers through ultrasonic-assisted ozone treatment ) 是由 安兴业 张润青 刘洪斌 刘利琴 张伟 于 2020-07-09 设计创作，主要内容包括：本发明公开了一种超声波辅助臭氧处理改善高得率竹浆纤维柔软度的方法,属于制浆造纸领域。其特征主要包括以下步骤：(1)将纤维原料打浆至打浆度为25°SR～35°SR；(2)加水调节纤维浆料的质量浓度至0.01wt％～5wt％,将稀释后的浆料放入超声波发生器进行超声波处理,超声波频率为15kHz～35kHz,功率为50W～1200W,并用冰水浴维持温度,超声波作用10min～120min；(3)将步骤(2)获得的浆料升温至10℃～80℃,通入臭氧气体,并作用1min～10min；(4)用同样的方法来定量分析步骤(3)获得纤维的单根纤维柔软度。本发明采用超声波结合臭氧来处理纸浆纤维,通过超声波的声空化效应,打开纤维结构,促进了后续臭氧处理的效率,改善了单根纤维的柔软性能。(The invention discloses a method for improving the softness of high-yield bamboo pulp fibers by ultrasonic-assisted ozone treatment, and belongs to the field of pulping and papermaking. The method is characterized by mainly comprising the following steps: (1) pulping the fiber raw material until the beating degree is 25-35 DEG SR; (2) adding water to adjust the mass concentration of the fiber slurry to 0.01-5 wt%, putting the diluted slurry into an ultrasonic generator for ultrasonic treatment, wherein the ultrasonic frequency is 15-35 kHz, the power is 50-1200W, and maintaining the temperature by using an ice-water bath for 10-120 min; (3) heating the slurry obtained in the step (2) to 10-80 ℃, introducing ozone gas, and acting for 1-10 min; (4) the individual fiber softness of the fibers obtained in step (3) was quantitatively analyzed in the same manner. The invention adopts ultrasonic wave and ozone to treat the paper pulp fiber, and opens the fiber structure through the acoustic cavitation effect of the ultrasonic wave, thereby promoting the efficiency of subsequent ozone treatment and improving the flexibility of single fiber.)

1. A method for improving the softness of high-yield bamboo pulp fibers by ultrasonic-assisted ozone treatment is characterized by comprising the following steps:

step 1: pulping the fiber raw material until the beating degree is 25-35 DEG SR or performing latency defibering to obtain pulp fiber;

step 2: adding water to adjust the mass concentration of the fiber slurry to 0.01-5 wt%, putting the diluted slurry into an ultrasonic generator, setting the action frequency of the ultrasonic generator to be 15-35 kHz and the power to be 50-1200W, and maintaining the temperature by using an ice-water bath for 10-120 min;

and step 3: heating the material obtained in the step (2) to 10-80 ℃, adjusting the concentration of the slurry to 0.5-8 wt%, adjusting the pH value to 1-4, introducing ozone gas, and treating the ozone for 1-10 min, wherein the amount of the ozone is 0.01-2 wt% (relative to the bamboo pulp fiber);

and 4, step 4: and (4) squeezing the water out of the material obtained in the step (3), and measuring the bending degree of the fiber by using a glass-metal wire method to quantitatively analyze the softness of the single fiber.

2. The method of claim 1, wherein: the action frequency of the ultrasonic generator is 15 kHz-35 kHz; the action power of the ultrasonic generator is 50W-1200W; the action time of the ultrasonic generator is 10 min-120 min.

3. The method of claim 1, wherein: the ozone action temperature is 10-80 ℃; the mass concentration of the ozone treatment slurry is 0.5-8 wt%; the pH value is adjusted to 1-4 in the ozone treatment process, and the ozone treatment time is 1-10 min; the ozone dosage is 0.01 wt% -2 wt%.

4. The method of claim 1, wherein: the softness of the fibers was measured using the glass-wire method.

Technical Field

The invention belongs to the field of pulping and papermaking, and particularly relates to a method for improving the softness of high-yield bamboo pulp fibers through ultrasonic-assisted ozone treatment.

Background

In china, bamboo pulp is a long-standing paper making material, and bamboos produced in china account for about 25% of the world. Compared with wood pulp, bamboo pulp has many advantages, in terms of raw materials, the growth cycle of bamboo is short, the bamboo pulp fiber resource is rich, therefore, the bamboo pulp fiber has great advantages in price, and the raw material cost is obviously saved. The bamboo pulp fiber is long and thin and has excellent paper forming performance when applied to the papermaking industry, and the internal composition of the bamboo pulp fiber has high cellulose content. However, the bamboo pulp fiber has some problems which cannot be ignored in the using process. For example, the bamboo pulp fiber is very stiff due to the fact that the inner cavity of the bamboo pulp fiber is circular and small, the fiber structure is relatively compact, for the high-yield bamboo pulp fiber, due to the influence of the pulping process, the content of lignin in the fiber is high, and the high-yield bamboo pulp fiber is poor in softness due to the series of factors. The softness of high-yield bamboo pulp fiber directly affects its application in many fields, such as paper products for daily use. Therefore, it is necessary and practical to find a method for effectively improving the softness of the high-yield bamboo pulp fiber.

Ozone, as a strong oxidant, can react with lignin to remove lignin from the fibers, thereby improving the softness of the bamboo pulp fibers. Compared with the traditional method for improving the softness of the fibers, the method has a series of advantages of low cost, quick treatment process, good effect, environmental friendliness and the like. However, the ozone treatment is often performed on the surface of the fiber, and the improvement of the softness performance is limited. The acoustic cavitation effect of ultrasonic wave can destroy the fiber structure for fibre inner structure exposes, is favorable to follow-up ozone to get into the inside and fibre of bamboo pulp fibre and reacts, thereby has improved the fibrous efficiency of ozone treatment, has improved fibrous softness performance simultaneously.

Disclosure of Invention

The invention provides a method capable of obviously improving the softness of high-yield bamboo pulp fibers, which utilizes the acoustic cavitation effect of ultrasonic waves, opens the compact structure of the bamboo pulp fibers while improving the softness of the fibers, and is beneficial to ozone molecules to enter the interior of the bamboo pulp fiber structure in the subsequent ozone treatment process, thereby providing a larger effective contact area for ozone treatment.

The invention provides a method for improving the softness of high-yield bamboo pulp fibers by ultrasonic-assisted ozone treatment, which can improve the accessibility of ozone to the high-yield bamboo pulp fibers through ultrasonic pretreatment, thereby improving the efficiency of improving the softness of the fibers by ozone treatment, reducing the using amount of ozone and saving the cost.

The technical method of the invention is summarized as follows:

a method for improving the softness of high-yield bamboo pulp fibers by ultrasonic-assisted ozone treatment comprises the following steps:

step 1: pulping the high-yield bamboo pulp fiber raw material until the pulping degree is 25-35 DEG SR or performing latency defibering; obtaining fiber slurry;

step 2: adding water to adjust the mass concentration of the fiber slurry to 0.01-5 wt%, putting the diluted slurry into an ultrasonic generator, setting the action frequency of the ultrasonic generator to be 15-35 kHz and the power to be 50-1200W, maintaining the reaction temperature at room temperature by using an ice-water bath, and performing ultrasonic action for 10-120 min;

and step 3: heating the high-yield bamboo pulp fiber material obtained in the step 2 to 10-80 ℃ in a water bath, adjusting the concentration of the pulp to 0.5-8 wt%, and enabling the use amount of ozone to be 0.01-2 wt% (relative to the bamboo pulp fiber), wherein the action time of the ozone is 1-10 min;

and 4, step 4: and (3) squeezing out moisture from the fiber slurry obtained in the step (3), and measuring the softness of the single fiber by a method for quantitatively analyzing the softness of the fiber by measuring the bending degree of the fiber by a glass-metal wire method.

The invention adopts ultrasonic to process the slurry, when the fiber-water interface is affected by ultrasonic, the bubbles on the interface deform and disintegrate suddenly, micro air flow is generated on the surface of the fiber, the surface structure of the fiber is damaged, the devillicate brooming degree of the fiber is improved, the flexibility of the fiber is improved, and the contact area of the ozone processing fiber is increased. The method combining ultrasonic treatment and ozone treatment is simple and convenient to operate, green and safe, and has little environmental pollution; compared with pure ozone treatment, the method improves the efficiency of ozone treatment and has important significance for improving the softness of the bamboo pulp fiber.

Drawings

Fig. 1 is an SEM picture of raw high yield bamboo pulp fiber. FIG. 2 is SEM picture of high yield bamboo pulp fiber treated by ultrasonic wave (600W, 45 min). FIG. 3 is SEM picture of high yield bamboo pulp fiber after ultrasonic (600W, 45min) pretreatment and ozone treatment (0.1 wt% ozone amount, 5min treatment time). FIG. 4 is SEM picture of high yield bamboo pulp fiber treated with ozone without ultrasonic pretreatment (0.1 wt% ozone amount, 5min treatment time).

As can be seen from FIG. 1, the untreated high-yield bamboo pulp fiber has a smooth and complete surface, is stiff and has poor softness; FIG. 2 is an SEM picture of high-yield bamboo pulp fibers after ultrasonic treatment, and it is obvious that the ultrasonic treatment damages the compact surface structure of the fibers, so that the structure becomes loose, the devillicate brooming phenomenon appears on the surface, and the structure of the bamboo pulp fibers is opened; FIG. 3 is a picture of high-yield bamboo pulp fibers treated by ultrasonic waves and ozone, and it can be seen that the softness of the bamboo pulp fibers is further improved after the ozone treatment; FIG. 4 is a photograph showing the high yield bamboo pulp fiber treated directly with ozone without ultrasonic pretreatment, and it can be seen that the surface structure of the fiber is not greatly changed, but only a relatively small amount of fibrillation occurs, and the improvement of the softness is not large. As can be seen from the detailed comparison between fig. 3 and fig. 4, the ultrasonic pretreatment can effectively open the compact structure of the high-yield bamboo pulp fiber, provide a channel for ozone molecules to enter the fiber structure, and promote the ozone treatment efficiency, thereby further improving the softness of the high-yield bamboo pulp fiber.

Detailed Description

The invention will be more fully and more readily understood by reference to the following examples, which are given to illustrate the invention more clearly, and are not intended to limit the invention in any way.

Ozone gas of each embodiment case is generated by an ozone generator, the ozone generator is manufactured by Shenzhen Feili electrical appliance science and technology Limited, and the product model is FL-815Y; the ultrasonic generator of each embodiment was a scientific-II D-type ultrasonic generator. And are not intended to limit the invention.