Sorption potential of oil palm shell for the removal of chlorinated phenol from aqueous solution: Kinetic investigation

In this study, activated carbons (ACs) from oil palm shell (OPS) were prepared using the two-stage self-generated atmosphere method, comprising of a semi carbonization stage and a chemical activation stage, which were fixed at 300 oC and 500 oC respectively. The prepared adsorbents were tested in the removal of 2,4-dichlorophenol (2,4-DCP) from aqueous solution. The samples were impregnated by varying the zinc chloride (ZnCl2 ) to precursor (OPS) ratio, after which, the final products, ACs, underwent several aspects of chemical and physical characterizations, i.e. percentage of yield, moisture content, ash content, pH, porosity, adsorption kinetics and isotherms (2,4-DCP) and surface chemistry of the adsorbent. The results indicated that the percentage of yield, moisture content and ash content had increased in proportional to the increase in ZnCl2 ratio. It was found that AC4, with the impregnation ration of 1:4 (OPS:ZnCl2 ) had the highest adsorption capacity of 26.40 mg/g. While the maximum Brunauer, Emmett and Teller (BET) surface area of AC4 was found to be around 1020 m 2 /g. Adsorption studies indicated an increased in adsorption capacity in proportional to the increase in adsorbate initial concentration and adsorbent dosage, whereas a higher pH decreased the adsorption capacity. The adsorption isotherm of all the prepared ACs fitted well to the Langmuir model, while the sorption kinetics followed the pseudo-second order, indicating that the adsorption was a single layer chemisorption process

SORPTION POTENTIAL OF OIL PALM SHELL FOR THE REMOVAL OF CHLORINATED PHENOL FROM AQUEOUS SOLUTION:KINETIC INVESTIGATION

In this study, activated carbons (ACs) from oil palm shell (OPS) were prepared using the two-stage self-generated atmosphere method, comprising of a semicarbonization stage and a chemical activation stage, which were fixed at 300 oC and 500 oC espectively. The prepared adsorbents were tested in the removal of 2,4-dichlorophenol (2,4-DCP) from aqueous solution. The samples were impregnated by varying the zinc chloride (ZnCl2 ) to precursor (OPS) ratio, after which, the final products, ACs, underwent several aspects of chemical and physical haracterizations, i.e. percentage of yield, moisture content, ash content, pH, porosity, adsorption kinetics and isotherms (2,4-DCP) and surface chemistry of the adsorbent. The results indicated that the percentage of yield, moisture content and ash content had increased in proportional to the increase in ZnCl2 ratio. It was found that AC4, with the impregnation ration of 1:4 (OPS:ZnCl2 ) had the highest adsorption capacity of 26.40 mg/g. While the maximum Brunauer, Emmett and Teller (BET) surface area of AC4 was found to be around 1020 m2/g. Adsorption studies indicated an increased in adsorption capacity in proportional to the increase in adsorbate initial concentration and adsorbent dosage, whereas a higher pH decreased the adsorption capacity. The adsorption isotherm of all the prepared ACs fitted well to the Langmuir model, while the sorption kinetics followed the pseudo-second order, indicating that the adsorption was a single layer chemisorption process

Ultrasonic intensification as a tool for enhanced microbial biofuel yields

peer-reviewedUltrasonication has recently received attention as a novel bioprocessing tool for process intensification in many areas of downstream processing. Ultrasonic intensification (periodic ultrasonic treatment during the fermentation process) can result in a more effective homogenization of biomass and faster energy and mass transfer to biomass over short time periods which can result in enhanced microbial growth. Ultrasonic intensification can allow the rapid selective extraction of specific biomass components and can enhance product yields which can be of economic benefit. This review focuses on the role of ultrasonication in the extraction and yield enhancement of compounds from various microbial sources, specifically algal and cyanobacterial biomass with a focus on the production of biofuels. The operating principles associated with the process of ultrasonication and the influence of various operating conditions including ultrasonic frequency, power intensity, ultrasonic duration, reactor designs and kinetics applied for ultrasonic intensification are also described

Removal of chlorinated phenol from aqueous media by guava seed (Psidium guajava) tailored activated carbon

In this study, the activated carbons (ACs) were prepared from guava seeds via two stages activation. The dried guava seeds were semi-carbonized at 300 °C for 1 h, and then the carbonized samples were impregnated with zinc chloride (ZnCl2). The ZnCl2: sample impregnation ratios (w/w) were altered from 1:1 to 5:1. The ACs were characterized by the yield percentage, ash content, moisture content, pH value, adsorption quality of 2,4-dichlorophenol (2,4-DCP) and surface functional groups. The surface area of the best produced AC3 was found to be 919.40 m2 g−1. It was found that AC3 had highest 2,4-DCP adsorption capacity, which was 20.9 mg g−1. The 2,4-DCP adsorption kinetic of prepared AC3 was pseudo-second order with correlation value of 0.995. In addition, the 2,4-DCP adsorption capacity of AC3 was fitted to the Langmuir model with correlation coefficient value of 0.977, indicating that chemisorption was a major contributor to the adsorption process