The use of TAED in the last phase of CMP peroxide bleaching was written by Zeinaly, Farhad;Tabrizi, Ali Kazemi;Shakhes, Jalal;Zeinali, Nooshin. And the article was included in Nordic Pulp & Paper Research Journal in 2017.Category: amides-buliding-blocks This article mentions the following:
The alk. peroxide process is one of the bleaching processes used to bleach high-yield pulps. The two disadvantages concerning the bleaching of these pulps are pulp color reversion at the end of bleaching process, and the incomplete consumption of the peroxide. The effect of using TAED (tetra acetyl ethylene diamine), as an activator in the last phase of bleaching, on the process, as well as on the bleached pulp properties was the target of the present study. Single-stage alk. peroxide process was applied for bleaching of mixed hardwood chemi-mech. pulp (CMP, 85% yield). The treatments involved three different charges of peroxide (1.5, 2 and 3%) and of alkali (1.12, 1.5 and 2.25%, sodium hydroxide), with and without addition of TAED during the last phase of bleaching i.e. the last 10 min. The results indicated that the bleached pulp brightness and the bleaching process selectivity increased with the increase of the chems. charge, but with a descending tendency. The use of TAED, not only reduced the level of the alk. darkening, but also produced further improvement in the brightness and selectivity, and a reduction in the effluent COD load. Furthermore, the residual peroxide levels in TAED-activated treatments were low and negligible. In the experiment, the researchers used many compounds, for example, N,N-(Ethane-1,2-diyl)bis(N-acetylacetamide) (cas: 10543-57-4Category: amides-buliding-blocks).
N,N-(Ethane-1,2-diyl)bis(N-acetylacetamide) (cas: 10543-57-4) belongs to amides. The solubilities of amides and esters are roughly comparable. Typically amides are less soluble than comparable amines and carboxylic acids since these compounds can both donate and accept hydrogen bonds. Tertiary amides, with the important exception of N,N-dimethylformamide, exhibit low solubility in water. Amides are not in general accessible by the direct condensation of amines with carboxylic acids for two reasons: first, both components are readily deactivated by a transfer of a proton from the acid to the amine and second, the hydroxy unit on the carbonyl of the acid is a relatively poor leaving group. Nevertheless, the formation of five- and six-membered rings is often surprisingly simple provided that other factors can be brought into play to assist in the condensation.Category: amides-buliding-blocks
Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics