Current Organic Chemistry - Volume 17, Issue 15, 2013

There is a world- wide growing interest in using lignocellulosic raw material for the production of fuels and chemicals, particularly related to the pulp and paper industry, and this is no exception in Bangladesh. On the other hand, Bangladesh and other Southeast- Asian countries are densely populated, forest deficient, thus heavily dependent on agriculture residue for such a purpose. This study reviews the availability and suit Read More

Acetic acid is one of the promising bio-products following the Value Prior to Pulping (VPP) concept, which is one of the options for Integrated Forest Biorefinery. In a typical chemi-thermo-mechanical pulping (CTMP) process, the chemical pre-treatment may be retrofitted into the pre-extraction stage. The potential of pre-extraction of acetic acid under the conditions similar to a CTMP process was evaluated in this study. The pre- Read More

The effective use of prehydrolysis liquor (PHL), from the kraft-based dissolving pulp production process, may fit into the concept of integrated forest biorefinery (IFBR). The dissolved organics in the PHL include hemicelluloses, lignin, acetic acid, furfural and extractives. Adsorption of hemicelluloses and lignin onto the neutral sulphite semichemical (NSSC) pulp fibres may be a potential method of utilizing the dissolved Read More

The kraft-based dissolving pulp production process can be a model for the forest biorefinery concept. The objective of this study is to characterize the dissolved lignin present in the pre-hydrolysis liquor (PHL) to facilitate its subsequent use following the forest biorefinery concept. In this work, lignin was isolated from PHL by acidification using dilute H2SO4, followed by purification through dissolution in a dioxane solution (9:1) a Read More

Liquefaction of lignocellulosic biomass is a promising process to produce liquid biofuels and valuable chemicals. The main purpose of this work is to efficiently liquefy biomass into energy-dense bio-oils through direct liquefaction. Pinewood sawdust was liquefied in supercritical carbon dioxide (SCCO2) at various temperatures (225-375°C) and residence time (0-4 hours) with alkaline catalyst (K2CO3). The results showed that th Read More

In this study, mountain pine beetle (MPB, Dendroctonus ponderosae Hopkins) infested lodgepole pine (Pinus contorta Dougl.) barks were liquefied in phenol using sulfuric acid as the catalyst. Results showed that liquefaction conditions, such as reaction time, reaction temperature, phenol/bark ratio, and catalyst loading had significant effects on the liquefaction yield, free phenol content of the liquefied bark fraction and the prop Read More

Hydrolyzing the amorphous region of cellulose with high selectivity while protecting the crystalline region during acid hydrolysis of cellulose still remains a key technical barrier in cellulose hydrolysis and Microcrystalline Cellulose (MCC) production. This study investigated the effects of two transition metals (Fe3+ and Cu2+) on cellulose yield after acid hydrolysis, α-cellulose content and crystallinity of the Eucalyptus pulp cell Read More

This study focuses on the conversion of cellulose and hemicelluloses present in kenaf stalks into fermentable sugars using sulfuric acid pretreatment followed by enzymatic hydrolysis. The first step prior to pretreatment was to determine the compositions of hexose, pentose sugars and lignin in pulverized kenaf stalks. Pretreatment on kenaf was performed by varying three independent parameters: 1) reaction temp Read More

In this work, bio-based products from starch biopolymer and rape biomass were produced. The physicochemical properties at interface of the biodegradable composites were analyzed and the intrinsic tensile strength of the rape fibers was determined from biocomposites containing up to 40 wt% of starch substitution. Rape thermomechanical fibers showed potential to undergo efficient fiber/fiber joints, and this was eviden Read More

Rape biomass was the raw material for the preparation of thermomechanical fibers, and it was used to reinforce starch-based biopolymer. In this study, the mechanical properties of the produced biocomposites, including flexural strength, Young’ s and flexural moduli and impact strength, were characterized. Afterwards, the material properties were simulated to evaluate its suitability for substituting for oil-based raw mater Read More

Paper industry uses various wet-end chemicals mainly for process control and the production of paper products. Although this industry currently uses various oil-derived chemicals, such as cationic polyacrylamide and poly (aminoamide)-epichlorohydrin, the use of bio-based chemicals derived from lignocelluosic resources has attracted attention since they are renewable and environmentally-friendly. In this review paper, the cu Read More

The paper discusses the misuse of two familiar chemical words in the chemical literature, namely hydrolysis and catalysis. The splitting of the acetate ester linkage in acetylsalicylic acid or aspirin, which has different mechanisms according to the pH of the solution is used as an example.

Molecular imprinting is a powerful technique to form a synthetic polymer receptor with tailor-made binding sites. This article gives a short overview of the application of the principle of molecularly imprinted polymers (MIPs) in capillary electrochromatography (CEC). Some new developments of monolithic column and coating based on MIPs in CEC mode are presented. Lastly, the review also discusses their applications for separa Read More

Oxide nanocubes have received great research attention because of their unique chemical, optical, magnetic, and electrontransport properties, which are caused by the strong face-to-face interactions among the nanocubes. One of the main challenges in this field is how to realize larg-scale assembly oxide nanocubes in large scale. This review summarizes the recent progress in the organic solution- based routes for fabricati Read More

Graphene possesses outstanding electronic and structural properties and the possibility to functionalize it with different functional moieties has greatly broadened the scope of its applications. The copper (I) catalyzed azide-alkyne cycloaddition (CuAAC) reaction has been recently adopted as a universal coupling process with applications that extend far beyond organic synthesis to further challenging goals in chemistry, polyme Read More

Sodium nitrite and hydrogen peroxide are ubiquitous in bioorganic and environmental chemistry, and their role has been exceptionally important and under continuous investigation. Sodium nitrite is a potential source of cytotoxic peroxynitrite in biological systems, while in a tandem with hydrogen peroxide it may serve as a precursor of mutagenic aromatic nitro compounds in the environment. A biomimetic couple of sodi Read More