Mercerization process

Mercerization was discovered by John Mercer in England and the process is named after him mercerizing. The process of alkaline treatment of cotton was patented in 1850. Later Horace Lowe in England found that the glazing effect became even more pronounced when cold caustic soda acted on cotton under tension. He discovered the actual mercerizing process and applied for its patent in 1890. 

The recovery of caustic from the mercerization process is a common practice in the textile industry. Mercerizer rinse water is normally recovered when its concentration is above 2-3% and below this concentration it is discharged to waste treatment. An alternative to this procedure is to use an ultrafiltration membrane to filter caustic rinse water before the solution goes to the evaporator. A flow sheet diagram of caustic recovery solution is shown in Fig. 13-12. The clarified and concentrated solution is then ready for re-use and consumption of caustic is significantly decreased [59],... 

Sound basic information can be found in books. Books do a good job of furnishing information on the principles of the spinning, weaving, or mercerizing processes, for example. While the information on methods or such factors as speeds or concentrations may not be completely up to date, the principles are usually unchanged. 

In the mercerization process cotton is treated in a caustic soda solution of I0%-25% under stress. The process increases the diameter of the fibers, shortens them, and gives them a high lustre. 

In the mercerization process, cotton fabrics are usually treated with 20% NaOH solution under tension. Its purpose is to enhance the fabric s characteristics such as dye affinity, dimensional stability, tensile strength, and lustre [8,9]. The process must be controlled to ensure fabric quality. Dye shade variation is the most common quality problem related to mercerized fabrics. The conventional method for determining the degree of mercerization, barium activity number (BAN), is laborious and requires 6 h before a result is obtained, which makes the test unsuitable for process control. Determining the BAN has been the only accepted method for measuring the degree of mercerization. The BAN of mercerized fabric is determined by boiling the samples of mercerized and unmercerized fabrics in... 

Natural cellulose is now referred to as cellulose I. Cellulose 11 is obtained from cellulose I by the mercerization process, i.e., soaking and wash out with aqueous NaOH. The crystal structure of cellulose is shown in Fig. 1.20. Later researches have proposed variant crystal structures of cellulose (cellulose I [118], cellulose II [119, 120], and indeed a cellulose III [121], and cellulose IV [122]) different from the Meyer-Misch model. 

In the textile industry, the quality of mercerization process is usually estimated by means of sorption of barium hydroxide by cellulose from saturated solution. A characteristic of the process quality is a barium index BI = 100% where A and A ... 

Uses Penetrant for caustic scouring and mercerization processes Features Stabie to extreme ieveis of aikaii Cekapene F-DP2 [Cekai Spec.)... 

---