Cellulase production from spent sulfite liquor and paper-mill waste fiber

Applied Biochemistry and Biotechnology -     

Synthesis of cyanoethyl ethers of cellulose from flax fiber production waste

Conditions of preparation of cellulose cyanoethyl ethers with different degrees of substitution, based flax fiber production waste were examined. The chemical structure of the resulting cellulose ethers and variation of the structure of the cellulose materials during cyanoethylation were examined by IR-Fourier spectroscopy and X-ray diffraction analysis. The degree of substitution of cellulose ethers was examined in relation to cyanoethylation conditions and chemical composition of the initial cellulose materials.     

Catalytic two-step process for the production of propylene from bioethanol

Theoretical and Experimental Chemistry - On the basis of analysis and thermodynamic calculations of the reaction paths of the catalytic conversion of ethanol a two-step process is proposed for the...     

MnO2纳米粒子固载纤维素酶用于高效水解农业废弃物制备生物乙醇

纤维素酶是一种有效的纤维质类物质水解催化剂,工业应用时可通过固定化纤维素酶来降低其成本。本文将烟曲霉原变种JCF产生的纤维素酶固定在MnO2纳米颗粒上。 MnO2可提高纤维素酶的活性,并充当一个更好的载体。采用扫描电镜表征了所制MnO2纳米粒子及其负载纤维素酶的表面性质,以傅里叶变换红外光谱分析了固定在MnO2纳米粒子上纤维素酶的官能团性质。纤维素酶在MnO2纳米粒子上最大的固定化效率为75%。考察了固定化纤维素酶的活性、操作pH值、温度、热稳定性和重复使用性等性质。结果表明,所制固定化酶的稳定性比游离酶更高。固定于MnO2纳米粒子上的纤维素酶可用于纤维质类物质的水解反应,且能在较宽的温度和pH值范围内使用。表征结果证实了该催化剂具有非常高的催化纤维素类物质水解的活性。     

Polysaccharides prepared from sunflower production waste

The composition and content of polysaccharides recovered from various samples of sunflower husks by their sequential treatment with water, ammonium oxalate (or oxalic acid), and alkali were examined. The products were analyzed by X-ray diffraction and IR spectroscopy. Original Russian Text L.A. Zemnukhova, S.V. Tomshich, A.V. Kovekhova, L.Yu. Greben’, 2007, published in Zhurnal Prikladnoi Khimii, 2007, Vol. 80, No. 7, pp. 1200–1205.     

Improvement of saccharification process for bioethanol production from Undaria sp. by gamma irradiation

Recently, many research works have reported on improvements to the saccharification process that increase bioethanol production from cellulosic materials. Gamma irradiation has been studied as an effective method for the depolymerization of complex polysaccharides. In this study, the effect of gamma irradiation on saccharification of Undaria biomass for bioethanol production was investigated. The Undaria biomass was irradiated at doses of 0, 10, 50, 100, 200 and 500 kGy and then hydrolyzed using sulfuric acid. The effects of gamma irradiation were measured through microscopic analysis to determine morphological changes and concentration of the reducing sugar of hydrolysates. Microscopic images show that gamma irradiation causes structure breakage of the Undaria cell wall. The concentration of reducing sugar of hydrolysates significantly increased as a result of gamma irradiation, with or without acid hydrolysis. These results indicate that the combined method of gamma irradiation with acid hydrolysis can significantly improve the saccharification process for bioethanol production from marine algae materials.     

Amorphous silicon dioxide from waste of Ferroally production

The optimum conditions for the formation of amorphous silicon dioxide from wastes formed in ferroalloy production containing more than 99% of the main substance were determined and its physicochemical properties were studied.     

Extractive substances formed from buckwheat grain production waste

Properties of liquid and dry extracts produced in treatment of buckwheat fruit shells (husk) and straw with water or an acid solution were studied. The conditions of pigment concentration from aqueous extracts by ultrafiltration were determined.     

Preparation of ion-exchange fiber from polypropylene waste with grafted polyacrylic acid

A procedure was developed for preparing weakly acidic cation exchanger from polypropylene fiber wastes by grafting of acrylic acid to the preoxidized surface of the fiber in an aqueous solution.     

Improvement of the technology for reprocessing black liquors from kraft pulp production

A way to improve the kraft pulp production process via acid–base treatment of black liquor was suggested. Data on the process for kraft lignin production by the sulfuric acid procedure were substantiated.     

Availability of crop residues as sustainable feedstock for bioethanol production in North Carolina

The amount of corn stover and wheat straw that can be sustainably collected in North Carolina was estimated to be 0.64 and 0.16 million dry t/yr, respectively. More than 80% of these crop residues are located in the coastal area. The bioethanol potential from corn stover and wheat straw was estimated to be about 238 million L (63 million gal/yr) in North Carolina. The future location of ethanol plant in North Carolina was estimated based on feedstock demand and collection radius. It is possible to have four ethanol plants with feedstock demand of 400, 450, 500, and 640 dry t/d. The collection radii for these four ethanol plants are 46, 60, 42, and 67 km (28, 37, 26, and 42 miles), respectively. The best location for a bioethanol plant includes four counties (Beaufort, Hyde, Tyrrell, and Washington) with feedstock demand of 500 t/d and collection radius about 26 mile.     

Enhancing adsorption of heavy metal ions onto biobased nanofibers from waste pulp residues for application in wastewater treatment

Biobased nanofibers are increasingly considered in purification technologies due to their high mechanical properties, high specific surface area, versatile surface chemistry and natural abundance. In this work, cellulose and chitin nanofibers functionalized with carboxylate entities have been prepared from pulp residue (i.e., a waste product from the pulp and paper production) and crab shells, respectively, by chemically modifying the initial raw materials with the 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) mediated oxidation reaction followed by mechanical disintegration. A thorough investigation has first been carried out in order to evaluate the copper(II) adsorption capacity of the oxidized nanofibers. UV spectrophotometry, X-ray photoelectron spectroscopy and wavelength dispersive X-rays analysis have been employed as characterization tools for this purpose. Pristine nanofibers presented a relatively low content of negative charges on their surface thus adsorbing a low amount of copper(II). The copper adsorption capacity of the nanofibers was enhanced due to the oxidation treatment since the carboxylate groups introduced on the nanofibers surface constituted negative sites for electrostatic attraction of copper ions (Cu²⁺). The increase in copper adsorption on the nanofibers correlated both with the pH and carboxylate content and reached maximum values of 135 and 55 mg g^?1 for highly oxidized cellulose and chitin nanofibers, respectively. Furthermore, the metal ions could be easily removed from the contaminated nanofibers through a washing procedure in acidic water. Finally, the adsorption capacity of oxidized cellulose nanofibers for other metal ions, such as nickel(II), chromium(III) and zinc(II), was also demonstrated. We conclude that TEMPO oxidized biobased nanofibers from waste resources represent an inexpensive and efficient alternative to classical sorbents for heavy metal ions removal from contaminated water.     

Taguchi method optimization of wax production from pyrolysis of waste polypropylene

Present research deals with the conversion of waste commodity plastics to valuable commercial product in the form of wax by pyrolysis. Optimization of both processes yield and produced wax quality was performed by means of a statistical tool originally proposed by G. Taguchi, using temperature, catalyst, carrier gas, and dwell time as the parameters. The obtained wax was characterized by Raman spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. Yield of wax was found to be maximum when the parameters were 600 °C, Fe catalyst, nitrogen gas atmosphere, and 15 min time. However, stability of the wax was found to be optimum at 700 °C. Calorific value of the wax thus obtained was ~43 MJ kg^?1, which supports its suitability as fuels like other petroleum products.     

An eco-friendly technology for polysaccharide production from logging and sawing waste

A polysaccharide recovery technology was developed with intent to be used in integrated processing of larch biomass waste into practically significant arabinogalactan, pectin, and crystalline glucose suitable for medicinal, food-industry, and agricultural applications. Theoretical aspects were considered for arabinogalactan extraction from larch wood, in which procedure some of individual stages and the entire process cycle of arabinogalactan recovery on a pilot installation were optimized. The possibility of saccharification of larch wood-derived lignocellulosic residue into crystalline glucose was demonstrated. The results of a technological study on pectin polysaccharide isolation from larch bark were reported along with the findings concerning the membrane tropic activity of pectin and ability to form nanobiocomposites via interaction with transition and noble metal ions.     

Promising directions for utilization of glycerol-containing waste from biodiesel fuel production

The provided examples of utilization of glycerol and glycerol-containing media are far from completely reflecting the diversity of research works dedicated to this problem. Nevertheless, the presented works provide sufficiently convincing evidence on broad prospects for utilization of excess glycerol for obtainment of practically important products in the course of chemical and biotechnological processes.     

Secondary fibrous materials from cardboard and paper production and consumption waste

Some information characterizing wastepaper, including utilization rates, technical data of different fiber grades, and waste paper processing technologies, is presented in the article. Wastepaper obtained from different sources such as cardboard and paper production, production of various goods (e.g. printing companies), and cardboard and paper consumption (e.g. household waste) is also described.     

Copolymer from the waste products of styrene and maleic acid production

Influence of the process conditions on the production of “STAM” copolymer from waste products formed at join producing of styrene and propylene oxide, the acetophenone bottom residue at styrene rectification, with maleic acid. Effects of temperature, copolymerization process duration, weight ratio of acetophenone bottom residue to maleic acid and styrene content in the bottom residue are studied.