Bleaching Flax Roving With Poly(Acrylic Acid) Magnesium Salt As Oxygen Bleaching Stabilizer For Hydrogen Peroxide

Alkali-oxygen one-bath scouring and bleaching process of the flax roving was studied by using a new type of synthesized non-silicon oxygen bleaching stabilizer Poly(acrylic acid) magnesium instead of sodium silicate. Based on the analysis of the effects of single factors such as sodium hydroxide concentration, hydrogen peroxide concentration, temperature, time and the amount of the synthesized non-silicon oxygen bleaching stabilizer poly(acrylic acid) magnesium salt on the performance of the bleached flax roving, including the whiteness, the breaking tenacity, the capillary effect and the weight loss ratio. The optimal process for the application of the stabilizer was determined by orthogonal test, namely, hydrogen peroxide concentration 8.5 g/L, sodium hydroxide concentration 5 g/L, sodium bisulfite 3 g/L, sodium carbonate 3 g/L, the synthesized non-silicon oxygen bleaching stabilizer poly(acrylic acid) magnesium 5.5 g/L, scoured and bleached at 90 ℃ for 60 min, and the bath ratio was 25:1. Compared with the traditional oxygen bleaching stabilizer sodium silicate, it not only has good ability to inhibit the rapid decomposition of hydrogen peroxide, but also has the advantages of higher whiteness, higher capillary effect, good feel and breaking tenacity, and can effectively solve the "silicon scale" problem and improve the quality of flax products.

Synthesizing environmentally friendly non-silicone oxygen bleaching stabilizer for linen yarn using oligomeric acrylic acid

Using potassium peroxodisulfate as an initiator and acrylic acid as a monomer, an acrylic acid oligomer was synthesized and then compounded with magnesium salt to form a non-silicone oxygen bleaching stabilizer. By investigating the effects of reaction temperature, reaction time, initiator concentration, monomer concentration, and magnesium salt dosage on product performance, the effect of stabilizers on linen yarn bleaching was analyzed. The synthetic conditions of oxygen bleaching stabilizer were determined by orthogonal test method, namely, acrylic acid monomer concentration 25%, initiator dosage 5%, oligomeric acrylic acid and magnesium salt compound ratio 5:1, reaction temperature 65 °C, reaction time 4 h. At this time, the chelated iron value of the product was as high as 239.314 mg/g, and the chelated calcium value also reached 145.000 mg/g. The dosage of the synthesized stabilizer were determined to be 4 g/L through indicators such as the decomposition rate of hydrogen peroxide and whiteness. The results showed that the environmentally friendly non-silicone oxygen bleaching stabilizer not only had a good ability to inhibit the decomposition of hydrogen peroxide, but also provided bleached linen yarn with a superior degree of whiteness and less metal ion residue, which can effectively solve the “silicon scale” problem and improve the quality of the pre-treatmented products.

PENGARUH PEMUTIHAN OKSIGEN DUA TAHAP TERHADAP KUALITAS PULP Acacia mangium

In this study, the unbleached pulp was made in the laboratory by cooking conditions: Active Alkali (AA) 18%, Sulfidity (S) 32%, ratio 1: 4, maximum temperature 165 oC, with cooking time of 2 + 1.5 hours. Pulp with kappa number of 20.01 and 52.30% yield was produced. Oxygen bleaching process was varied into a single stage bleaching process, a two-stage bleaching process with and without washing. The results showed that the two stages oxygen bleaching processes, without washing with variation of NaOH addition 100:0 and 80:20 gave the higher reduction of kappa number and the increasing of bleaching yield compare to one stage oxygen bleaching. The higher reduction of kappa number gave the higher of reduction of viscosity, but had no effect on fiber composition. Two oxygen stage bleaching without washing is recommended.Key words : oxygen bleaching, kappa number, viscosity, yield filtered ABSTRAKPada penelitian ini pulp belum putih dibuat di laboratorium dengan kondisi pemasakan : AA 18 %, S 32 %, rasio 1 : 4, temperatur maksimum 165 OC, dan waktu 2 + 1,5 jam. Dihasilkan pulp dengan bilangan kappa 20,01 dan rendemen tersaring 52,30 %. Proses pemutihan oksigen divariasi menjadi proses pemutihan satu tahap, proses pemutihan dua tahap dengan dan tanpa pencucian. Hasil penelitian menunjukkan pemutihan oksigen dua tahap tanpa proses pencucian dengan variasi penambahan NaOH 100 : 0 dan 80 : 20 memberikan penurunan bilangan kappa yang lebih besar dan peningkatan rendemen pemutihan dibanding dengan pemutihan oksigen satu tahap. Penurunan viskositas sebanding dengan penurunan bilangan kappa, dimana semakin besar penurunan bilangan kappa juga mengakibatkan penurunan viskositas yang semakin besar tetapi tidak berpengaruh terhadap komposisi serat. Pemutihan oksigen dua tahap tanpa proses pencucian sangat disarankan. Kata kunci : pemutihan oksigen, bilangan kappa, viskositas, rendemen tersaring

Research on the Bleaching Process of the Non-Silicon Oxygen Bleaching Stabilizer

In this study, a type of non-silicon oxygen bleaching stabilizer was used to cotton fabric in the hydrogen peroxide bleaching process. This type of novel non-silicon oxygen bleaching stabilizer was prepared mainly with ethylene diamine tetraacetic acid (EDTA) and magnesium chloride. The results showed that adding the non-silicon oxygen bleaching stabilizer into the bleaching solution obviously decreased the hydrogen peroxide decomposition rate and improved the fabric whiteness. Optimal conditions was found as follow: non-silicon oxygen bleaching stabilizer 4.5 g/l; bleaching temperature 75-85 °C; pH of bleaching liquid 11; bleaching time 40-45 min. In summary, the results showed that the self-made non-silicon oxygen bleaching stabilizer could make the cotton fabrics obtained great whiteness, capillary ability and breaking strength.

Study on Xylanase-Aided Bleaching of Wheat Straw KP

Before oxygen bleaching and hydrogen peroxide bleaching, wheat straw pulp was bleached using xylanase. The effect of enzymatic stage on pulp properties and bleachability has been studied and compared with reference (control) pulps, processed without enzyme addition. Experimental results showed that, the optimal concentration of wheat straw pulp was 10%, the optimal treatment time and dose of enzyme was 60 min and 1.25AXU/g respectively. Oxygen pressure decreased from 0.6MPa to 0.5MPa when conditions of hydrogen peroxide bleachingremained unchanged and wheat straw pulp achieved the same whiteness. Hydrogen peroxide consumption decreased from 2% to 1.8% when oxygen bleaching has the same conditions and achieved the same white degree.