JP-7856738-B1 - Pulp digestion accelerator and method for producing pulp using the same

Abstract

[Problem] To provide a digestion accelerator that can efficiently digest lignocellulose material when producing pulp by digesting lignocellulose material. [Solution] A digestion accelerator characterized by containing at least one of lecithin and its derivatives, and phosphatidylcholine, and preferably further containing a sulfur-containing compound. [Selection Diagram] None

Inventors

• 田中 多加志
• 山田 理生

Assignees

• 日華化学株式会社

Dates

Publication Date

20260511

Application Date

20241225

Claims (5)

1. A digestion accelerator characterized by containing at least one of lecithin and its derivatives, and phosphatidylcholine.
2. The digestion accelerator according to claim 1, further characterized by containing a sulfur-containing compound.
3. The pulping accelerator according to claim 2, characterized in that the sulfur-containing compound is at least one salt selected from the group consisting of hydrogen sulfide, sulfite, bisulfite, disulfite, thiosulfate, dithionite, dithionate, disulfate, peroxomonosulfate, peroxodisulfate, and polythionate.
4. A method for producing pulp, comprising the steps of: preparing a digestate containing a digestion accelerator according to any one of claims 1 to 3; and performing a digestion treatment using the digestate.
5. The method for producing pulp according to claim 4, characterized in that, in the step of preparing a digestate containing the digestion accelerator according to claim 2 or 3, at least one of the lecithin and its derivatives, and the phosphatidylcholine, is mixed with the sulfur-containing compound beforehand and then added to the digestate.

Description

This invention relates to a pulping accelerator and a method for producing pulp using the same, and more specifically, to a pulping accelerator for lignocellulose materials and a method for producing pulp using the same. To produce pulp from lignocellulose materials such as wood, a pulp-making process using alkalis and sulfites is generally performed. This pulp-making process dissolves or disperses unwanted lignin and natural resin components. These components are then removed by filtration and washing, resulting in the production of pulp. On the other hand, natural resources such as timber are subject to restrictions on over-logging due to environmental concerns, and timber prices are currently high. Therefore, increasing pulp production per unit of raw timber and producing high-quality pulp products has become crucial. One known method to address these challenges is the use of digestion accelerators. For example, Japanese Patent Publication No. 53-74101 (Patent Document 1) discloses a method for producing pulp, characterized in that, in a pulping process in which lignocellulose material is treated with an alkaline chemical solution or a chemical solution containing sulfites to produce pulp, hydroxyanthracene or a hydroxyanthracene derivative is added as a pulping aid to a pulp solution consisting of an alkaline chemical solution or a chemical solution containing sulfites, and the lignocellulose material is pulped by the alkaline method or the sulfite method. While adding hydroxyanthracene or a hydroxyanthracene derivative to the pulp solution accelerates the pulping process, it is not always sufficient. Furthermore, anthracenes are a cause for concern as carcinogenic substances, and since their effects on the human body cannot be completely eliminated, it is necessary to reduce their use. Therefore, there is a need for pulping aids (pulping accelerators) to replace hydroxyanthracene and hydroxyanthracene derivatives. Furthermore, Japanese Patent Publication No. 2020-2481 (Patent Document 2) discloses a pulping accelerator containing at least one of glucose and fructose. While adding at least one of glucose and fructose to the pulping solution accelerates the pulping process, it was not always sufficient. Japanese Unexamined Patent Publication No. 53-74101Japanese Patent Publication No. 2020-2481 The present invention will be described in detail below with reference to its preferred embodiments. The following description of preferred embodiments is essentially illustrative and is not intended to limit the present invention, its applications, or its uses. [Digestion accelerator] First, the digestion accelerator of the present invention will be described. The digestion accelerator of the present invention contains at least one of lecithin and its derivatives, and phosphatidylcholine. In this specification, lecithin and its derivatives, and phosphatidylcholine will be collectively referred to as the "main component of the digestion accelerator." (Lecithin and its derivatives) In the present invention, lecithin and its derivatives (hereinafter collectively referred to as "lecithins") act as digestion accelerators when digesting lignocellulose material. Lecithin is a general term for mixtures mainly composed of various phospholipids. Specifically, it is a mixture of major phospholipids represented by phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, and phosphatidic acid, and other phospholipids (lecithin in a broad sense). There are no particular restrictions on such lecithin; for example, it may be derived from plants, animals, or microorganisms. Furthermore, it may be used directly extracted from living organisms such as plants, animals, or microorganisms, or purified. Synthetic lecithin can also be used. Examples of plant-derived lecithin include those derived from soybeans, rapeseed, wheat, rice, corn, cottonseed, safflower, flaxseed, sesame, and sunflower seeds, while examples of animal-derived lecithin include those derived from egg yolk and milk. Furthermore, examples of lecithin derivatives include the hydrogenated lecithin (lecithin with hydrogenated fatty acids), enzymatic hydrolysates (lecithin obtained by enzymatic hydrolysis), and fractionated products (lecithin with altered concentrations of specific phospholipids (fractionated lecithin)). These lecithins may be used individually or in combination of two or more. Among these lecithins, plant-derived lecithins, animal-derived lecithins, and their derivatives are preferred from the viewpoint of promoting pulverization. From the viewpoint of safety and cost, plant-derived lecithins and their derivatives are more preferred, and soybean-derived lecithins and sunflower seed-derived lecithins are even more preferred. (Phosphatidylcholine) In the present invention, phosphatidylcholine acts as a digestion accelerator when digesting lignocellulose material. Phosphatidylcholine is one of the major phospholipids that make up lecithin. Whil