NISCAIR Online Periodicals Repository Collection: IJCT Vol.16(6) [November 2009]

Alkoxygen and alkoxygen-AQ delignification of Ipomea carnea and Cannabis sativa

Thu, 29 Oct 2009 22:58:59 GMT

Title: Alkoxygen and alkoxygen-AQ delignification of Ipomea carnea and Cannabis sativa

Authors: Dutt, Dharm; Tyagi, C H; Agnihotri, Swarnima; Kumar, Alok; Siddhartha

Abstract: Molecular oxygen is a specific oxidizing agent for lignin but its low solubility in cooking liquor causes a serious problem of mass transfer in a heterogeneous chemical pulping process with wood. The anatomy of Ipomea carnea and Cannabis sativa permit much easier diffusion and penetration of the molecular oxygen into the reactive zones of fiber wall. The low lignin content and more open and looser fiber structure of I. carnea and C. sativa makes them suitable for alkoxygen delignification. Due to their identical cooking conditions except liquor to wood ratio mixed cooking of I. carnea and C. sativa by alkoxygen delignification process is able to produce good quality pulp because the pulp blend has unique morphological characteristics of I. carnea which resembles with softwoods with respect to cell wall thickness and lumen diameter along with long fibers of C. sativa in which I. carnea deficits. The present study aims at optimizing the various operating parameters of alkoxygen delignification process for I. carnea and C. sativa. An oxygen pressure of 10 kg/cm²at16% alkali dose, cooking temperature of 160⁰C for 120 min produces screened pulp yield 53.5% at kappa number 30 for C. sativa and 46.1% at kappa number 27 for I. carnea. The addition of 0.1% AQ at O₂ pressure of 10 kg/cm² improves pulp yield by 1.6% for C. sativa and 1.1% for I. carnea with a decrease of kappa number by 2 units in both the cases. I. carnea shows good bleaching response compared to C. sativa. Therefore, I. carnea pulp may be used as brightness improver to enhance the overall brightness of the blend.

Page(s): 523-528

Enhanced viability of Bacillus coagulans after spray drying with calcium lactate, storage and re-hydration

Thu, 29 Oct 2009 22:58:59 GMT

Title: Enhanced viability of Bacillus coagulans after spray drying with calcium lactate, storage and re-hydration

Authors: Yadav, A K; Chaudhari, A B; Kothari, R M

Abstract: The present work has provided an alternative probiotic preparation, which is easily scalable for commercial operations in eco-friendly and cost-effective manner. Spray drying being a proven technology compared to convective current, infra-red exposure and lyophilization, it will make visible impact on production, sale and use of Bacillus coagulans as an effective probiotic preparation.

Page(s): 519-522

Effects of impurities on oxygen transfer rate in the electroflotation process

Thu, 29 Oct 2009 22:58:59 GMT

Title: Effects of impurities on oxygen transfer rate in the electroflotation process

Authors: Kotti, M; Dammak, N; Ksentini, I; Mansour, L Ben

Abstract: In this work, three different types of impurities: soybean oil, surfactant and diatomaceous earth were doped to simulate the impurities in wastewaters issued from edible oil refinery plant. The effects of the impurities on the oxygen transfer rate were investigated in an electroflotation cell. The volumetric mass transfer coefficientwas studied for a batch mode involving different values of the current density for different impurities concentrations. The capacity of oxygenation and the corrective alpha factor were also studied. Models which relate the volumetric mass transfer coefficient to the current density and the concentration of the impurities were established. The results showed that the presence of impurities significantly reduce the volumetric mass transfer coefficient K_La.

Page(s): 513-518

Tailoring of Guar gum for desert sand stabilization

Thu, 29 Oct 2009 22:58:59 GMT

Title: Tailoring of Guar gum for desert sand stabilization

Authors: Gupta, Satish Chandra; Hooda, K S; Mathur, N K; Gupta, S

Abstract: A low viscosity grade guar gum has been developed by two techniques i.e. gamma irradiation and H₂O₂ treatment. The desired viscosity is achieved by controlling the quantity of hydrogen peroxide solution or the -irradiation dose. The viscosity of 1% guar gum was reduced from 3240 cps to 116 cps using10% H₂O₂ solution (50% v/v) and from 3203 cps to 222 cps using 6 kGy -irradiation dose. The reduced viscosity was stabilized by adding 0.5% solution of formaldehyde (37% v/v) or by using 0.5% cobalt naphthenate. The low viscosity grade guar gum powder and the solutions stabilized with cobalt naphthenate or formaldehyde could be stored for long periods without loss of viscosity. The reduced viscosity guar gum is used for grouting stabilization of sand for construction works across desert.

Page(s): 507-512