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Highlights • Dehydration of harvested paddy at room temperature. • Chitosan membrane drier is an alternative method for drying paddy rice. • The chitosan membrane drier removed water vapor from moist air by a vapor permeation process. • The chitosan membrane drier could reduce the moisture content of harvested paddy rice from 23 to 16% within 1 h. Abstract A chitosan membrane was used to separate water vapor evaporated from moist paddy rice out of the apparatus, called the "membrane drier". It was aimed as an alternative method to dry harvested paddy instead of the traditional open air technique that can encounter rain or flooding problems. The prototype membrane drier was designed from a mathematical air flow pattern analysis, where it was found that a horizontal flow mode with a baffle plate and triangle air flow path (HFwBF&TFP) was the most appropriate feature. The chitosan membranes studied in this research were uncrosslinked dense (UCD), crosslinked dense (CD), uncrosslinked composite-on-spunbond (UCC) and crosslinked composite-on-spunbond (CC) membranes. The highest drying rate of the membrane drier equipped with UCD, CD, UCC and CC membranes occurred in the first hour of operation at 46.4 ± 0.4, 51.7 ± 6.7, 57.8 ± 0.9 and 71.5 ± 4.9 g-water/kg-moist-paddy/h, respectively. Compared to the drying rate by the open air technique and a hot air oven at 40 °C (52.7 ± 0.7 and 40.2 ± 0.7 g-water/kg-moist-paddy/h, respectively), the chitosan membrane drier could be used as an alternative method for drying biomass, such as paddy rice. The CC chitosan membrane drier could reduce the moisture content of harvested paddy rice from 22.8 ± 0.4 to 15.7 ± 0.9% within 1 h. [ABSTRACT FROM AUTHOR]

The question about the influence of temperature condition on uniformity of drying of components of raw cotton and on their quality in drum driers has not been studied thoroughly. In the article you can find practical recommendations on choosing the drying conditions depending on initial moisture of raw cotton, output of the dryable material, which guarantee maximal keeping of natural properties of fiber and seeds. [ABSTRACT FROM AUTHOR]

Oxovanadium(IV) 2-ethylhexanoate was established as a new primary drier for alkyd-based paints. A series of experiments has demonstrated an excellent drying activity toward solvent-borne alkyd resins of different oil length at considerably lower metal concentration than optimal for commercial cobalt(II) 2-ethylhexanoate. The behavior in real paint was simulated on formulations bearing inhibitor of autooxidation. The detailed studies of the drying process have shown that the relatively slow initial step of autooxidation reaction, when compared with cobalt compounds, is compensated for by the absence of the induction times. Furthermore, the active oxovanadium(IV) species are not consumed during the drying processes as evidenced by EPR spectroscopic measurements. [ABSTRACT FROM AUTHOR]

Oxovanadium(IV) compounds, [VO( O , O -R 1 COCHCOR 2 ) 2 ] (R 1 = R 2 = Me; R 1 = Me, R 2 = Ph; R 1 = R 2 = Ph), were established as a new class of environmentally friendly primary driers for solvent-borne alkyd binder. The performed experiments clearly show that the catalytic activity of oxovanadium compounds is, in some terms, considerably higher than observed for commercial cobalt-based drier ( Co-Nuodex ). The detailed study of the drying process reveals several differences in mechanism of autoxidation. The enhanced activity at low concentrations together with very low overall toxicity imply the oxovanadium compounds as promising catalysts of autoxidation reactions implying a great perspective in paint-producing industry. [ABSTRACT FROM AUTHOR]

Highlights: [•] Molybdenum-based catalyst was used as alkyd drier. [•] Drying activity was established. [•] Mechanism of drying process was studied by infrared spectroscopy. [ABSTRACT FROM AUTHOR]

Soybean oil was metathesized with the standard homogenous metathesis catalyst, which consisted of tungsten hexachloride (WCl6) and tetramethyl tin (Me4Sn) in chlorobenzene as solvent. The reactions were terminated at different time intervals. Soybean oil was mixed with metathesized soybean oil in the presence of cobalt-drier to evaluate drying properties. Five weight percentage (% w) of metathesized oil was found to be all that was needed to decrease the drying time of soybean oil from 312 to 182 min. Drying times for heat-polymerized soybean oil with Gardner-Holdt viscosity of Z1–Z2 and Z3–Z4 were 71 and 75 min, respectively. In both cases, 5% weight metathesized soybean oil in the blend gave the best results for reducing drying time to 67 and 69 min, respectively. [ABSTRACT FROM AUTHOR]