JPS6253203B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to antifoaming agents for preventing aqueous foaming in the pulp and paper industry. Foaming in the pulp and paper industry is caused by the addition of sizing agents, bands, starches, resins, casein, titanium oxide, talc, clay, dyes, etc., resulting in decreased production efficiency, loss of production materials, damage to production machinery, Causes wastewater pollution. To date, mineral oil, paraffin,
Antifoaming agents such as silicone resins, higher alcohols, fatty acid esters, and nonionic activators have been used, but mineral oils, paraffin, and higher alcohols are insoluble in water, so they lack quick effectiveness, and they tend to adhere to fibers. Although silicone resin has a good antifoaming effect, it is expensive and its use is limited.
In addition, although nonionic surfactants have good dispersibility in aqueous systems, they each have drawbacks such as generally poor effectiveness. On the other hand, among fatty acid esters, glycerin monoester has a great effect when combined with mineral oil or wax, and this is also described in USP 2715614. However, monoglycerides of stearic acid and oleic acid have poor antifoaming effects, and adding mineral oil or wax to monoglycerides of stearic acid and oleic acid increases the antifoaming effect, but
If it is diluted with a large amount of water, it will form a deposit,
It has the disadvantage of causing fiber adhesion. In order to eliminate such drawbacks, as a result of various studies, 0.5 to 30 parts by weight of a monoester or diester of tall oil first distillate with an acid value of 90 to 170 and glycerin, or a mixture thereof, is added to 100 parts by weight. alkali salts of fatty acids, polyalkylene glycol esters of fatty acids with HLB 9.0 or more, polyalkylene glycol esters of resin acids with HLB 9.0 or more, and
An antifoaming agent containing one or more emulsifiers selected from the group consisting of polyhydric alcohol esters of fatty acids with an HLB of 9.0 or higher and adjusted to an HLB of 2.4 to 4.0 has the ability to break foam and suppress foam. The present invention was completed based on the discovery that it has both of the following effects, has excellent sustainability, and does not form deposits even when diluted with a large amount of water. The tall oil first distillate used in the present invention contains 50 to 80% by weight of fatty acids such as palmitic acid and oleic acid.
Contains 20-50% by weight of unsaponifiables. Unsaponifiable substances in the first distillate of tall oil do not form deposits like mineral oil or wax even when diluted with a large amount of water, increasing the antifoaming effect. The lower limit of the acid value of the first distillate of tall oil was set at 90 because, given the general capacity of the crude tall oil rectifier, it would be difficult to obtain a first distillate with an acid value lower than this in terms of operational efficiency. This is because it lacks industrial economic efficiency, and if the acid value is not 90 or higher, the glycerin ester concentration decreases and the defoaming ability decreases. The reason why the upper limit is limited to 170 is that if this value is exceeded, the HLB value of the antifoaming agent becomes high and the antifoaming effect becomes poor. Also, the reason why the HLB of the polyalkylene glycol ester of fatty acid or resin acid and the polyhydric alcohol ester of fatty acid was set to 9.0 or more is that this HLB
If it is less than 9.0, its function as an emulsifier is insufficient and it is difficult to emulsify the system. The reason why the emulsifier is limited to 0.5 to 30 parts by weight is as follows.
It is unnecessary to use more than 30 parts by weight, as it will actually reduce the foaming prevention ability of the product, and if less than 0.5 parts by weight, it will be difficult to obtain a uniform emulsified liquid. Furthermore, the reason why the HLB of the mixed system is limited to 2.4 to 4.0 is that when it is less than 2.4, the antifoaming effect is poor, and when it is more than 4.0, the antifoaming effect is poor and foaming becomes more likely. . According to the present invention, the excellent antifoaming agent is, for example, based on 100 parts by weight of tall oil initial distillate having an acid value of 90 to 170.
Add 7 to 30 parts by weight of glycerin and heat at 200 to 250℃ for 2 hours.
After reaction for ~8 hours, 0.5 to 30 parts by weight of an emulsifier is added to 100 parts by weight of the obtained reaction product, and then water is added and emulsified to easily obtain the product. Furthermore, when a polyalkylene glycol ester or polyhydric alcohol ester of a fatty acid is used as an emulsifier, the same desired product can be obtained even if it is charged and reacted simultaneously with glycerin. The present invention will be explained below with reference to Examples. Example 1 Acid value was set in a reaction vessel equipped with a stirring device and a condensing device.
100 parts by weight of tall oil first distillate of No. 165, 27 parts by weight of glycerin, polyethylene glycol (average molecular weight
Add 0.7 parts by weight of 1000), raise the temperature to 235℃ under Chituso gas, continue heating at 235℃ for 2 hours, and calculate the weight of glycerin monoester of tall oil first distillate and polyethylene glycol monoester of tall oil first distillate. 120 parts by weight of reaction product were obtained, corresponding to a ratio of 99:1. Transfer 100 parts by weight of this reaction product to an emulsification pot,
Antifoaming agent A was obtained by adding 400 parts by weight of hot water while stirring while maintaining the liquid temperature at 70°C. (HLB3.0) Example 2 Into the reaction vessel described in Example 1, 100 parts by weight of tall oil first distillate with an acid value of 90 and 11 parts by weight of glycerin were charged.
Heating was continued at 250° C. for 6 hours under Tituso gas to obtain 105 parts by weight of a reaction product corresponding to a weight ratio of 1:1 of tall oil first distillate glycerin monoester and tall oil first distillate glycerin diester. 100 parts by weight of this reaction product was transferred to an emulsification pot, and the polyethylene glycol of tall rosin (average molecular weight
460) Antifoaming agent B was obtained by adding 27 parts by weight of ester and adding 508 parts by weight of hot water while stirring while keeping the liquid temperature at 70°C. (HLB3.7) Example 3 Put 100 parts by weight of the same reaction product as in Example 2 into an emulsification pot, add 2.1 parts by weight of tall rosin polyethylene glycol (average molecular weight 460) ester with HLB 12.0, and raise the liquid temperature to 70°C. Add hot water under stirring while keeping
Antifoaming agent C was obtained by adding 408 parts by weight. (HLB2.6) Example 4 In the same reaction apparatus as in Example 1, 11.5 parts by weight of glycerin was charged to 100 parts by weight of the first distillate of tall oil with an acid value of 140, and heating was continued at 235°C for 6 hours under Chituso gas. Glycerin diester of tall oil first distillate
105 parts by weight were obtained. 100 parts by weight of this reaction product was transferred to an emulsification tank, 12.4 parts by weight of potassium oleate was added, and 450 parts by weight of hot water was added while stirring while maintaining the liquid temperature at 70°C to obtain antifoaming agent D. (HLB3.0) Comparative Example Monoglyceryl stearate was used as comparative antifoaming agent E. Example 5 Defoaming test Rosin-based sizing agent HR-50 (Harima Kasei Kogyo Co., Ltd.)
2% aluminum sulfate aqueous solution was added under stirring to adjust the pH to 9.0, 7.0, and 5.0, which was used as a foaming solution. 300 g of the foaming liquid was weighed, and a predetermined amount of an antifoaming agent diluted with water was added using a whole pipette and mixed. The foam height after 5 minutes was measured using the Ross Miles method (JIS K-3362). The results are shown in Tables 1, 2, and 3.

【table】

【table】

[Table] Example 6 Sizing test A rosin-based sizing agent HR-50 (manufactured by Harima Kasei Kogyo Co., Ltd.) was added and mixed in an amount containing 0.5% by weight as solid content into a slurry of bleached softwood pulp for paper making. ,
Immediately before paper making, antifoaming agents A to D are added to the resulting slurry in an amount of 0.05 to 0.2% by weight based on the pulp content in the slurry.
Add and mix. At this time, no foaming occurred,
There was no deposit and no decrease in size was observed.

Claims (1)

[Claims] 1. 0.5 to 30 parts by weight of a fatty acid alkali salt, a fatty acid with an HLB of 9.0 or more, or polyalkylene glycol esters of resin acids, and
For a paper pulp manufacturing process characterized by adding and mixing an emulsifier consisting of one or more selected from the group consisting of polyhydric alcohol esters of fatty acids with an HLB of 9.0 or higher to adjust the HLB to 2.4 to 4.0. Antifoaming agent.