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Utilization of Black Liquor as Urease Inhibitor for Ammonia Reduction

100%

Sarwono A. , Widiantara M. D. , Zahra N. L. , Floresyona D. , Suryawan I. W. K. , Siagian F. M. H. , Septiariva I. Y.

2022

tom Vol. 23, iss. 2

213--218

Urea fertilizers in agricultural operations usually tend to produce large amounts of ammonia due to hydrolysis, therefore contribute to the air pollution. The purpose of this study was to study the potential black liquor from pulp industry as urease inhibitor. Characterization of the black liquor was carried out by Spectrophotometer Fourier Transform Infra-Red (FTIR) and Thermal Gravimetric Analyzer (TGA) instruments. Meanwhile, the determination of ammonia levels was carried out using UV-spectrophotometer. The black liquor used in this process contains OH stretching, C=O stretching, an aromatic ring vibration, ring vibration, and guaiacil ring vibration indicating the presence of lignin. TGA primary weight loss in black liquor occurs above 200 °C. The addition of urease enzymes to urea tends to increase the release of ammonia. Meanwhile, the results showed that black liquor could prevent the nitrogen loss of urea.

Effect of Black Liquor from Date Palm on the Workability and Compressive Strength of Portland Cement and Concrete

72%

Irekti A. , Oualit M. , Siahmed H. , Buncianu D. , Zibouche F.

tom Vol. 19, nr 3(61)

5--18

Lignin is the second most abundant natural polymer. Due to the high content of carbon and hydrogen (C-H, C-C, C=O), it can be used as a potential dispersant for cement matrix. The objective of this study is to extract lignin from date palm and study its effect in the form of black liquor (BL) on the rheological and physic-mechanical properties of the cements and concrete. The lignin in black liquor form represents approximately 30 wt% dry weight of date palm. It is a heteropolymer composed primarily of methoxylated phenylpropylene alcohol monomeric units interconnected by a variety of stable carbon-carbon and carbon-oxygen-carbon (ether and esters) linkages. The results found show the positive effect on the workability of cement and concrete and confirms its dispersion effect by improving compressive strength of concrete during the early and the later ages of hydration.