“Fabrication of cellulose acetate/ lead acetate blend membrane for hydrogen separation”
Abstract: herein, we present successful fabrication of cellulose acetate (CA)/(PdOAc)2 blend membranes for gas-permeation performance of H2 separation. , CO2, and CH4 gases. Pure CA and CA/(PdOAc)2 blend membranes with different concentrations (0.5, 0.75 and 1 wt %) were prepared following a vapour induced phase separation (VIPS) method. The membranes were investigated via various techniques such as ATR-IR to study the interaction between the CA and (PdOAc)2. Followed by FESEM which exhibited the surface and cross sectional morphology in which the homogeneous blending of CA and (PdOAc)2 was established. XRD patterns revealed the crystallinity and amorphous phase of the membranes. The change in mechanical strength of the blends on addition of (PdOAc)2 into CA matrix was deliberated by tensile strength analysis. Gas transport experiments were carried out using H2, CO2, and CH4 gases at operating pressures of 1 atm. The gas permeation results showcased highest permeability of 13.7 Barrer for H2 gas with permeability followed by CO2 (6.8 Barrer) and least by CH4 (0.2 Barrer) for the best performed CA/(PdOAc)2 blend membrane.
“Biomineralization, dissolution studies of silicate bioceramic prepared from eggshell and rice husk”
Abstract: the current investigation aims to replace the synthetic starting materials with biowaste to synthesize silicate bioceramics. Pure silica from rice husk was extracted by decomposition of rice husk in muffle furnace followed by alkali treatment and acid precipitation. Raw eggshell and extracted silica were utilized for the preparation of wollastonite and forsterite by the solid-state method. The TG-DSC analysis shows that the crystallization temperature of wollastonite and forsterite was found to be 883 oC and 980 oC, respectively. The phase purity of wollastonite was attained at 1100 oC whereas forsterite was composed of secondary phases even after calcination at 1300 oC. These materials behaved differently when exposed to the physiological environment, as wollastonite exhibited remarkable apatite deposition within 3 days whereas forsterite shows the formation of apatite phase after five weeks of immersion. Dissolution studies indicated that phosphorus and calcium play a key role in apatite formation whereas Mg2+ ion has negligible involvement during biomineralization. MTT assay further confirmed the cytocompatibility of bioceramics.