Chemical Engineering

The metal taking capacity of several types of biomass, agro products and by-products has gained attention during recent years. In the present study, one such material i.e., coconut shell powder was chosen as the biosorbent for the removal of Cu(II) from aqueous solutions. The adsorption capacity of this sorbent was investigated by batch experiments. High adsorption (>90 %) is achieved in the present study.

The present environmental concerns over fly ash disposal have sparked interest in its conversion to value added product such as adsorbent. Fly ash derived from coal residues has a potential for conversion to adsorbent. Still more remarkable is the subsequent utilization of theses adsorbent synthesized from fly ash as adsorbent for removal of dye and heavy metals in the industry. In the present study the coal based fly ash was used to synthesis adsorbent by alkali fusion, followed by hydrothermal treatment. The synthesis is carried out by thermal method with a temperature of 5500C. Based on adsorption batch studies it can be concluded that the adsorbent developed in the present study is fairly effectieve in the removal of Methyl Red and K2Cr2O7 solution.

Microwave-assisted extraction (MAE) was employed for production of carbohydrates from corn pericarp which is a waste of corn starch production by using hot compressed water as a solvent. Carbohydrates consist of glucose, xylose, arabinose and hemicellulose, while residues were composed of cellulose. By increasing the heating temperature, the solubilization rate increases and reached the value of 75.2% at 220 °C. In order to increase the carbohydrate yield the four independent variables such as heating temperature, come-up time, heating time and solid to liquid ratio were optimized by using the response surface methodology techniques. It includes fractional factorial design, the path of steepest ascent and central composite design. Subsequently, we have applied 2-step of experimental design including fractional factorial design and central composite design for accurate prediction of the optimum condition of MAE of carbohydrates from corn pericarp. In this paper, the total recycle of the corn pericarp have been done by investigating the detailed effects of microwave irradiation on chemical components in corn pericarp. The maximum yield of carbohydrates is about 70.8 % with predominant production of xylo-oligosaccharides.