Modeling of lead (II) adsorption on sodium hydroxide treated rice husk: fixed-bed studies

Sodium hydroxide treated rice husk was explored as an adsorbent for the removal of lead (II) ions from aqueous solutions in a column studies. This paper evaluate the effect of flow rates of 3 mL/min and 9 mL/min; bed depth of 0.9 cm, 1.8 cm and 2.8 cm and influent lead concentration of 5 mg/L and 20 mg/L on the adsorption capacity of the sample in fixed-bed mode were investigated. The highest adsorption capacity of 78 % using 20 mg/L initial lead (II) ions solution was achieved at flow rate of 9 mL/min and bed depth of 2.8 cm. The experimental results obtained from the adsorption studies were correlated with the Thomas, Adams– Bohart and Yoon–Nelson models. The results of the adsorption parameters showed that, Adams–Bohart model fitted the adsorption studies well over all the other models

Chemical research projects office functions accomplishments programs

Basic and applied research in the fields of polymer chemistry, polymeric composites, chemical engineering, and biophysical chemistry is summarized. Emphasis is placed on fire safety and human survivability as they relate to commercial and military aircraft, high-rise buildings, mines and rapid transit transportation. Materials systems and other fire control systems developed for aerospace applications and applied to national domestic needs are described along with bench-scale and full-scale tests conducted to demonstrate the improvements in performance obtained through the utilization of these materials and fire control measures

NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 35)

Abstracts are provided for 58 patents and patent applications entered into the NASA scientific and technical information systems during the period January 1989 through June 1989. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application

An introduction to photocatalysis through methylene blue photodegradation

International audienceWe described a simple experimental setup for a lab work on the photocatalytic degradation of methylene blue by T iO 2 nanoparticles. The photocatalysis process can be used for many applications. Treatments for diluted wastewaters industries, air purifying in underground car parks, preventing fouling on glass surfaces, these are some of the things this phenomenon has the ability to do. The described experiment is easy to perform and the interpretation can be easily adapted to different level of students: from high school students demonstrating their interests on a sustainable development, to students who are getting Masters in the science department that want to propose a full explanation of all the phenomenon of the photocatalytic process. Starting by a description of the experimental setup , we analysed the photocatalyst nanoparticles and applied the Langmuir-Hinshelwood model to our experimental data. Finally we discussed shortly on the respective energetic levels of the photocatalyst semiconductor and the methylene blue

Estimating Combustion Kinetics of UAE Date Palm tree Biomass using Thermogravimetric Analysis

Palm tree consists of different parts among which are the leaflet, rachis and fibers. All these parts constitute lignocellulose biomass components capable of producing value added end products. A kinetic study of thermal decomposition of UAE date palm tree of phoenix dicteylifera species was carried out using thermal gravimetric analysis (TGA) at heating rates 10 oC/min, 15 oC/min and 20 oC/min. Most of the lignocellulose material decomposed between 300 oC and 650 oC at each heating rate. The rachis decomposed in three phases while the leaflet and fibers decomposed in two phases. The apparent activation energies increased from 54 to 476 kJ/mol, 55 to 458 kJ/mol and 84 to 329 kJ/mol for leaflet, rachis and fibers, respectively for conversion ranging from 10-% to 80-%. Results from this study are fundamental in optimizing operational conditions of a reactor for production of furfural, levulunic acid, dihydroeugenol, DHE and 2,6-dimethoxy-4-propyl phenol, DMPP as high value chemicals. Key words: UAE Palm tree biomass, Thermogravimetric analysis, Combustion kinetics, Activation energ

On the Electrostatics of Pneumatic Conveying of Granular Materials

In this work the electrostatics of the pneumatic conveying of granular materials in a non-conducting (PVC) vertical pipe is studied using Electrical Capacitance Tomography (ECT) system. The non-conducting wall in general attains static charges arising from particle-wall collisions in the initial periods of conveying process and then reaches equilibrium with the surroundings. The polarity of particles and conveying pipe inner wall agrees reasonably well with the contact potential difference measurements. The perturbations in the capacitance signal due to charge accumulation are larger with smaller air superficial velocity. The denser flow regimes give larger wall residual charge. Wall charging process shows similar trend by surface potential and ECT measurements. The addition of small amount (0.5% by weight) of anti-static agent (Larostat-519) in the powder form decreases the electrostatic charge generation by altering the patterns for particle-particle and particle-wall collisions.Singapore-MIT Alliance (SMA

NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 31)

Abstracts are provided for 85 patents and patent applications entered into the NASA scientific and technical information system during the period January 1987 through June 1987. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application

NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 18)

Abstracts are cited for 120 patents and patent applications for patents introduced into the NASA scientific system during the period of July 1980 through December 1980. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or application for patent

Klason Method: An Effective Method for Isolation of Lignin Fractions from Date Palm Biomass Waste

Klason lignin extraction method is one of the robust techniques for isolation of lignin from lignocellulosic palm biomass waste for future production of High Value Chemicals (HVCs). To elucidate the mechanism of hemicellulose and cellulose glycosidic bond distraction, lignocellulos

Experimental studies on extraction of valuable fuels from karanja and neem seed by pyrolysis

Today we see everywhere that oil has become inherent part of our daily life. Every activity is dependent on the requirement of fuels be it directly or indirectly. The demand of fuels is increasing day by day. Import dependence for oil in India which is about 70 per cent, is likely to increase further. As we all know that the petroleum resources are limited and are non-renewable in nature, we must start to think about the alternatives as we are likely to run out of the petroleum resources in few decades or so. Stress must be given to production of energy from renewable sources as they are biodegradable and non-toxic. Here an attempt has made to study the feasibility of production of valuable fuels from natural but non edible seeds such as karanja and neem seeds by the method of pyrolysis. Here the production of the fuel can serve purpose of alternative fuels as biomass pyrolysis oil has potential to be used as fuel oil or its substitute