Improper drying

Most of Voacanga seeds have a brown color the moisture content was below the 12%, the maximum percentage according to international standards for botanical products. Only 5 samples exceeded that amount (Table I), indicating that these seeds were improperly dried. High moisture content can decrease shelf life due to microbial growth and enzymatic reaction, leading to seed deterioration. 

Figure 2. Dried and acceptable quality Griffonia seeds (left), poorly dried seeds (upper right), typical endosperm (yellow) of good quality well-dried seed (lower right), endosperm of an improperly dried seed (lower left).

Drying of various feedstocks is needed for one or several of the following reasons need for easy-to-handle free-flowing solids, preservation and storage, reduction in cost of transportation, achieving desired quality of product, etc. In many processes, improper drying may lead to irreversible damage to product quality and hence a nonsalable product. 

It must be emphasized here that aU Friedel—Crafts catalysts are strongly hygroscopic and decompose in improperly dried solvents, although indications can be found in the Hterature that small traces of water or alcohols act as activating co-catalysts. In any case attention must be paid to the purity of the solvent selected for the post-crossHnking reaction. 

Silver streaks, splay Wet material due to improper drying, high percent regrind, over wet virgin resin Follow resin manufacturer s drying instructions and dryer manufacturer s operating and maintenance instructions Use desiccant dryer... 

Poor dryer maintenance leads to inactive desiccants, air leaks in hoses, clogged filters, defective heaters, and the inability to maintain a low dew point of the drying air. Parts made from improperly dried or wet resins should not be reground for reuse if the plastic is subject to hydrolysis. Degradation by hydrolysis destroys properties and is not reversible. 

Reducing the residence time and/or lowering the test temperature can help with this problem. Improper drying of the material can also cause this problem. 

It is necessary to take into account that the water molecules can appear not only due to improper drying of the system, but can even be products of different side reactions. For example, they are formed on modification of (warm) aUcoxide solutions with carboxylic acids (Stenou, 1998) ... 

Improper drying Loss of strength 2% 2 10% 0.90 1.8 Brittle failure Increase cross sectional area implement process controls... 

Improper drying Loss of toughness 2% 1 10% 0.90 0.9 Brittle failure Investigate further... 

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