Effects of pyrolysis temperature on the physicochemical properties of empty fruit bunch and rice husk biochars.

Biochar has received great attention recently due to its potential to improve soil fertility and immobilize contaminants as well as serving as a way of carbon sequestration and therefore a possible carbon sink. In this work, a series of biochars were produced from empty fruit bunch (EFB) and rice husk (RH) by slow pyrolysis at different temperatures (350, 500, and 650°C) and their physicochemical properties were analysed. The results indicate that porosity, ash content, electrical conductivity (EC), and pH value of both EFB and RH biochars were increased with temperature; however, yield, cation exchange capacity (CEC), and H, C, and N content were decreased with increasing pyrolysis temperature. The Fourier transform IR spectra were similar for both RH and EFB biochars but the functional groups were more distinct in the EFB biochar spectra. There were reductions in the amount of functional groups as pyrolysis temperature increased especially for the EFB biochar. However, total acidity of the functional groups increased with pyrolysis temperature for both biochars.

Gasification of oil palm empty fruit bunches: a characterization and kinetic study.

Empty fruit bunches (EFBs), a waste material from the palm oil industry, were subjected to pyrolysis and gasification. A high content of volatiles (>82%) increased the reactivity of EFBs, and more than 90% decomposed at 700°C; however, a high content of moisture (>50%) and oxygen (>45%) resulted in a low calorific value. Thermogravimetric analysis demonstrated that the higher the heating rate and the smaller the particle size, the higher the peak and final reaction temperatures. The least squares estimation for a first-order reaction model was used to study the degradation kinetics. The values of activation energy increased from 61.14 to 73.76 and from 40.06 to 47.99kJ/mol when the EFB particle size increased from 0.3 to 1.0mm for holocellulose and lignin degradation stages, respectively. The fuel characteristics of EFB are comparable to those of other biomasses and EFB can be considered a good candidate for gasification.

In vitro antimicrobial and cytotoxic activities of leaves and flowers extracts from Lippia alba.

The research was conducted to investigate the in vitro antimicrobial and cytotoxic activities of leaves and flowers extract extracted from Lippia alba. Disc diffusion technique was used for in vitro antibacterial and antifungal screening. Zones of inhibition were observed in disc diffusion for antibacterial screening against 4 Gram-positive pathogenic and 6 Gram-negative pathogenic bacteria. Among crude extracts chloroform extract showed good activity against all test organisms. A Large zone of inhibition was observed (18 mm) against Vibrio parahaemolyticus. In antifungal screening, the compound showed mild to moderate zones of inhibition against four tested organisms. A Large zone of inhibition was observed against Aspergillus niger (13 mm). Cytotoxic activities of crude extracts were determined using Brine shrimp lethality Bioassay and LC50 values of standard Vincristin sulphate as positive control, n-hexane and crude ethanol extracts were found to be 5, 15 and 20 microg mL(-1), respectively.