Humic Acids from Raw Materials of the Czech Republic [1 ed.] 9781617610356, 9781616689650

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Copyright © 2010. Nova Science Publishers, Incorporated. All rights reserved. Humic Acids from Raw Materials of the Czech Republic, Nova Science Publishers, Incorporated, 2010. ProQuest Ebook Central,

Copyright © 2010. Nova Science Publishers, Incorporated. All rights reserved. Humic Acids from Raw Materials of the Czech Republic, Nova Science Publishers, Incorporated, 2010. ProQuest Ebook

CHEMISTRY RESEARCH AND APPLICATIONS

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HUMIC ACIDS FROM RAW MATERIALS OF THE CZECH REPUBLIC

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CHEMISTRY RESEARCH AND APPLICATIONS

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HUMIC ACIDS FROM RAW MATERIALS OF THE CZECH REPUBLIC

LIBUŠE MADRONOVÁ EDITOR

Nova Science Publishers, Inc. New York

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Copyright © 2011 by Nova Science Publishers, Inc. All rights reserved. No part of this book may be reproduced, stored in a retrieval system or transmitted in any form or by any means: electronic, electrostatic, magnetic, tape, mechanical photocopying, recording or otherwise without the written permission of the Publisher. For permission to use material from this book please contact us: Telephone 631-231-7269; Fax 631-231-8175 Web Site: http://www.novapublishers.com

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Independent verification should be sought for any data, advice or recommendations contained in this book. In addition, no responsibility is assumed by the publisher for any injury and/or damage to persons or property arising from any methods, products, instructions, ideas or otherwise contained in this publication. This publication is designed to provide accurate and authoritative information with regard to the subject matter covered herein. It is sold with the clear understanding that the Publisher is not engaged in rendering legal or any other professional services. If legal or any other expert assistance is required, the services of a competent person should be sought. FROM A DECLARATION OF PARTICIPANTS JOINTLY ADOPTED BY A COMMITTEE OF THE AMERICAN BAR ASSOCIATION AND A COMMITTEE OF PUBLISHERS. Additional color graphics may be available in the e-book version of this book.

LIBRARY OF CONGRESS CATALOGING-IN-PUBLICATION DATA Humic acids from raw materials of the Czech Republic / editor, Libuse Madronova. p. cm. Includes bibliographical references and index.

ISBN:  (eBook) 1. Humic acid. I. Madronova, Libuse. QD341.A2H85175 2010 631.4'17--dc22 2010025955

Published by Nova Science Publishers, Inc. † New York

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CONTENTS   vii 

Preface Chapter 1

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Chapter 2

Chapter 3

Chapter 4

Chapter 5

Preparation and Elemental Composition Libuše Madronová, Jaromír Novák, Josef Kozler and František Novák

1 

 

FTIR Spectra Vladimír Machovič,, František Novák, Libuše Madronová and Jaromír Novák

21 

13

33 

C NMR Spectra in the Liquid and Solid States Richard Hrabal, Jiří Brus, Libuše Madronová and František Novák Determination of OH Groups by Wet Chemical Methods Pavel Kuráň, Pavel Janoš, Libuše Madronová and František Novák Determination of Molecular Weights and Correlations with the E4/E6 Ratio Libuše Madronová, Pavel Janoš and František Novák

 

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  45 

  59 

vi Chapter 6

Chapter 7

Chapter 8

Contents Thermal Analysis, Correlation between Physical and Chemical Properties of Humic Acids Jiří Kučerík, František Novák, Libuše Madronová and Jaromír Novák Biological Activity Determination Libuše Madronová, Jaromír Novák, Jaroslav Kubíček, Barbora Antošová Josef Kozler and František Novák Oxidation of Coal-based Raw Materials by Nitric Acid Jaromír Novák,, František Novák, Libuše Madronová, Vladimír Machovič and Josef Kozler

69 

  83 

  103 

121

Index

123

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List of Symbols

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PREFACE In the period of more than twenty years, the Research Institute of Inorganic Chemistry in the Czech Republic, together with various other universities, research institutes and commercial organizations, worked on projects concerned with humic substances. The main reason was that the Czech Republic is rich in deposits of various raw materials potentially suitable for the production of humic substances. Main goals of the investigations were the selection of raw materials, as well as the determination of their chemical and physical properties. This book presents the results of these extensive investigation. Chapter 1- The preparation of alkali humates and humic acids from raw materials of Czech Republic (coal, oxyhumolite, lignite, and peat) was aimed. Chosen preparation methods can be implemented in low tonnage technologies and in industrial production. The aim was to get substances available for application in biotechnologies and in human and veterinary medicine. Suspensions prepared by alkali extraction, executed aerobic in the suspension with use of potassium hydroxide were purified by sedimentation and centrifugation. Humic acids obtained from the refined potassium humate solutions by coagulation by sulfuric acid were after separation by filtration rinsed and dried at the room temperature. Other substances were prepared from coal and lignite after their oxidation by nitric acid. Raw materials and substances prepared from them were compared on the basis of their chemical and physical properties. Basic characteristics – the moisture, ash, organic part, fulvic acids, leachable humic substances, functional groups (total acidity and carboxyl groups) content, inorganic

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viii

Libuše Madronová

constituents in humic substances (water-free), and organic elemental analysis are presented. Chapter 2- The infrared spectra of humic acids from peat, soil, coal, oxidized coal, and oxyhumolite were obtained using the diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy. For structural evaluation, three regions of the DRIFT spectra were used: 3800–3100, 3000–2800, and 1900–1500 cm-1, which corresponds to hydroxyl, aliphatic, and aromatic/carbonyl/nitro structures, respectively. The band height ratios of the above mentioned bands seem to be suitable parameters for rapid structural characterization of humic acids and raw materials. DRIFT represents an excellent spectroscopy technique for characterizing of humic materials in neat form without alkali halide matrix, which can alter the spectra by ionic exchange reactions with the analyte. Chapter 3- Sixteen humic acids isolated from important organic deposits in the Czech Republic were characterized using both liquid and solid-state 13C NMR spectra with the aim to determine their structure and parameters of their biological activity. Despite of methodical differences among single NMR experiments, a relatively good agreement was achieved in the determination of aromaticity by both NMR methods. The highest aromaticity from liquid state NMR was found for chernozem HA. High aromaticity, above 65 %, was found for lignite humic acids. Aromaticity of oxyhumolite humic acids was also relatively high, with the values between 53.9 and 63.9 %. Mediocre aromaticity between 40.5–46.7 % was found for coal humic acid. Peat humic acids displayed the lowest aromaticity of all studied samples, 28.1–31.4 %. Their low aromaticity is caused by a high content of alkoxy carbons from polysaccharide chains. Carboxyl-C content of studied HA ranged from 4.7 to 28.2 % with the mean of 19.9 %. The lowest content of carboxyl-C was found in the coal humic acid C3A. HA from oxidized coal, oxyhumolite from the mine Jiří, and from lignite have carboxyl-C content slightly above 8 %. The highest content of carboxyl carbon was found in soil HA (19.2 %), HA Fluka (20.8 %) and HA from oxidized oxyhumolite of the mine Jiří (28.2 %). In carboxyl-C content, the LS and CP/MAS methods differed more, than in the other carbon types. In spite of this, values from both NMR methods were comparable. A significant correlation was found between carboxyl-C determined by LS NMR and the total acidity, determined by traditional Ba(OH)2 method. The correlation of biological activity and hydrophilicity/hydrophobicity ratio parameters was negative, which means, that a high hydrophilicity is an

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Preface

ix

essential but not a sufficient condition for the high biological efficiency of humic acids. Chapter 4- As a part of our research work on characterization of HS functional groups the methylation of HA with dimethylsulfate in both acetone and methanol was evaluated for the determination of the OH group’s content. Observed differences in the determination of the OH group’s content obtained by methylation with dimethylsulfate in acetone and methanol were interpreted on the basis of different polarity of the used solvents resulting in different alkalinity of reaction mixture. These results were compared and discussed with other structural information obtained by classical chemical methods and from titration curves. The contents of carboxylic, phenolic, and alcoholic groups as well as some other minor –OH groups were estimated from total OH contents obtained after methylation in both solvents in combination with the results of the conventional determinations of acidic functional groups as well as titration curves. Finally, on the basis of obtained results the brief characterization of analyzed HA samples regarding their functional OH groups was done. Chapter 5- Molecular weights Mn and Mw and E4/E6 ratios of humic acids samples prepared from coal, oxyhumolite, lignite, peat, and chernozem from different localities in the Czech Republic were measured. Some samples were prepared from raw materials after their oxidation by nitric acid. The SEC (size-exclusion chromatography) was used to determine molecular weights;, the absorbance at wavelengths 465 and 665 nm were determined by the UVVIS spectrometry. Experimental results confirmed the E4/E6 ratio decrease with growing molecular weights. Determined E4/E6 ratios and molecular weights were further compared with other basic characteristics – total acidity, carboxyl groups content, carbon and oxygen content. Chapter 6- Selected humic acids extracted from coals mined in different localities in the Czech Republic, their oxidated derivatives, one sample from Chernozem, and a commercially- available product, Fluka, were subjected to the analysis using differential scanning calorimetry and thermogravimetry. Experimental data showed significant differences in stabilities, affinities to water (moisture), ash content and combustion heats. Sample Fluka showed remarkably high content of ash and it was rejected from further considerations. Further, it was found the negative correlation between stability and N content. Combustion heat measured from degradation temperature up to 600 °C using DSC indicated relationship with the aromaticity degree of humic acids under

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study. On the contrary, no significant relationship was found between combustion heat and C/H ratio. Chapter 7- The biological activity of potassium humate samples were investigated on higher plants. Humate samples were prepared through alkaline extraction of coal, oxyhumolite, lignite, peat, and chernozem originated from Czech Republic. The fast method based on the roots length measurement was used. Their growth rate is influenced by the stimulative effect of an investigated substance which was put into the essentials nutrient solution. The length of germinal roots were measured after 48, 72, and 96 hours from seeds insertion in the experimental vessels. Maize (Zea mays) was chosen as the test plant The correlation of carboxyl groups and intensity of HS stimulative effect on the stretch growth of higher plants was found in the longer time intervals (r2 = 0.43). The methodology of potassium humate foliar application was verified in the case of wheat growing in hydroponics arrangement. The significant effect of humic substances application was established in the case of roots matter growth in the earliest stages. Humic substances have also the prosperous effect on zinc uptake by plants. The zinc concentration in the above-ground part of plants enhanced even by 24 % and in roots even by 128 % in consequence of enhancement of its transport into roots, always compared with individual ZnSO4.7H2O application. Chapter 8- This chapter describes the process of oxidation of coal-based raw materials in solid phase by nitric acid. The procedure was designed so that it can also be realizsed on a larger industrial scale. Two coal raw materials from deposits in the Czech Republic were chosen for this research: coal from the Družba open-cast mine in the Sokolov Coal Basin, and lignite from the mine in Mikulčice belonging to the Vienna Basin. There is a description of the technological parameters of coal-based raw material oxidation by nitric acid as well as an evaluation of the consumption of nitric acid in relation to the amount of organic matter entering the process, and the achieved content of leachable humic substances in the products prepared. Oxidized products were used for the preparation of alkali nitrohumates from which nitrohumic acids were prepared. The chapter presents the chemical and structural parameters of the starting raw materials and the prepared products. The biological activity of the produced potassium nitrohumates was also evaluated.

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Chapter 1

PREPARATION AND ELEMENTAL COMPOSITION Libuše Madronová1,*, Jaromír Novák1, Josef Kozler 1 and František Novák 2 1

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Research Institute of Inorganic Chemistry, Revoluční 84, 400 01 Ústí nad Labem, Czech Republic 2 Biology Centre of the Academy of Sciences of the Czech Republic, v. v. i., Institute of Soil Biology, Na Sádkách 7, 370 05 České Budějovice, Czech Republic

ABSTRACT The preparation of alkali humates and humic acids from raw materials of Czech Republic (coal, oxyhumolite, lignite, and peat) was aimed. Chosen preparation methods can be implemented in low tonnage technologies and in industrial production. The aim was to get substances available for application in biotechnologies and in human and veterinary medicine. Suspensions prepared by alkali extraction, executed aerobic in the suspension with use of potassium hydroxide were purified by sedimentation and centrifugation. Humic acids obtained from the refined *

E-mail address: [email protected] (L. Madronová). Tel. +420 474 521 893. (Corresponding author.)

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Libuše Madronová, Jaromír Novák, Josef Kozler et al. potassium humate solutions by coagulation by sulfuric acid were after separation by filtration rinsed and dried at the room temperature. Other substances were prepared from coal and lignite after their oxidation by nitric acid. Raw materials and substances prepared from them were compared on the basis of their chemical and physical properties. Basic characteristics – the moisture, ash, organic part, fulvic acids, leachable humic substances, functional groups (total acidity and carboxyl groups) content, inorganic constituents in humic substances (water-free), and organic elemental analysis are presented.

Keywords: Humic substances, coal, oxyhumolite, lignite, peat, alkali extraction, coagulation, organic elemental analysis

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1. INTRODUCTION Humic substances (HS) are constituents of the organic matter of soil, peat, surface waters, marine and lake sediments, sedimentary rocks, coals, etc. The major elements of the HS are carbon, hydrogen, oxygen and further nitrogen and sulfur. Their content differs according to the mining locality. HS are classified into three groups: humin, humic acid (HA) and fulvic acid (FA). Chemic structure of the native HS is very complicated. They are composed of many complex molecules, and they contain substituted aromatic polycarboxylitic acids with –OH groups, aliphatic acids, quinones, hetero-cykles containing O and N and various amino acids. They further contain lignin, polysaccharides, monosaccharides and proteins fragments. These components of molecules are linked together by numerous types of bonds (–O–, –NH–, – N=, >CH2, >C=O, –S– and longer carbon chains), which occur in different rate [1]. The structure of HS is various and differs according to a raw material which is isolated from. Particular HS raw materials went through geochemical changes of original organic matter and their huminification degree differs. Properties and structure of HS are also influenced by the preparation processes being used for their isolation. According to the complex structure and properties of HS, it is necessary to use a large number of analytical methods to characterize them. Basis of HS description is the quantitative composition determination of organic and inorganic part. By the HA and FA ratio, molecular weight is

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further determined. The functional group (FS) content is important for ionexchanging properties. HS molecular structure (aromatic and aliphatic carbon, reactive functional groups content) is identified by infrared (IR) spectroscopy and by the 13C nuclear magnetic resonance (NMR) [1]. For statistical analysis and correlation of laboratory data, a number of humic acids were prepared from raw materials available in Czech Republic (CR). Four raw materials types were used – brown coal, naturally oxidized brown coal (oxyhumolite), lignite and peat. Oxyhumolites were created via long-term weathering of brown coal in the upper beds of brown coal deposits in the north and northwest of the CR after Krušné mountains folding. These materials are so called secondary HS and they are equivalent to leonardite. Lignite samples are from the southeast part of the CR (Wien Basin) and peat from the deposits in the southwest part of the CR (these materials are primary HS). All raw materials of the CR are described in detail in the previous paper [2]. Our former paper [3] results were used for the choice of preparation methods, which could be able to transfer into the industrial utilization in the range of low tonnage technology with the use of usual technologic apparatus. The influence on the biology activity of products was also taken into account [4]. The determination of basic characteristics, inorganic constituents and elemental organic analysis in HS was aimed in this chapter. Elemental analysis determinates content of C, H, N, S, and O. As the empirical parameter the atomic ratio H/C, which determines the aromaticity (as lower its value the more aromatic character is). Though the elemental analysis gives no information about form of the each binding in HS molecules, the information gained by this method is valuable, especially together with measured spectral analysis. N and S content is the important parameter, these elements partakes in the formation of heterocycles and function groups and they contribute significantly to chelatic and sorb abilities of HS. Further properties and structure characteristics are presented in following chapters: FTIR spectra evaluation (Chapter 2), NMR spectra measured in the solution as well as in the solid state (Chapter 3), the functional groups determination (Chapter 4) using the methods described in papers [5, 6], the determination of molecular weights using the method [7] and their correlation with E4/E6 ratios (Chapter 5), the determination of the thermal analysis (Chapter 6), and the determination of the biological activity (Chapter 7).

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2. EXPERIMENTAL 2.1. Materials Raw materials chosen for the HA preparations were: brown coal from two localities – Sokolov basin, mine Družba - samples C1, C3, mine Jiří - sample C4, oxyhumolite from localities – Most basin, mine Václav - samples X1, X2, mine Vršany - sample X3, – Sokolov basin, mine Marie -sample X4, mine Jiří - sample X5, lignite - Wien Basin, mine Mikulčice (in CR) - sample L1, peat from two localities - Branná - sample P1, Světlík - sample P2. To compare properties of prepared HA from coal raw materials and peat, Ha from chernozem of an agriculturally-exploited field in Radovesice (north of ČR) - sample S.

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2.2. Preparation All preparations were done aerobically in order properties of prepared samples be influenced by oxidation processes, which could run during the isolation [8]. Raw materials were modified before the chemical treatment. Oxyhumolite and lignite samples have been crushed and ground into pieces of particles dimension 1 mm. Particles bigger than 10 mm were removed from peat. Chernozem was decalcinated before alkaline extraction by repeated stirring with sulphuric acid and decantation. According to the HS application in biotechnology, H2SO4 was used to the decalcination because the use of HCl could be the cause of HS chlorination and thereby the damage of biological efficiency. Potassium humate (HK) was obtained by alkaline extraction with KOH in the stirred reactor. Conditions of the alkali extraction were: temperature 70 °C, extraction time 2 hours and such KOH amount to guarantee pH of obtained HK solution to be in the range 9–10. The KOH amount necessary for the extraction from each raw material is influenced by the extractable HS content (HSL) and the ash content. To reach the required pH, mass ratio KOH/ HS was

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need ca 0.3 was for oxyhumolite with the higher HSL content 0.5 for oxyhumolite poorer on HSL. In the case of the brown coal with the low content HSL (C3H), the alkaline extraction was done first at the lower pH (9–9.5). This extract was eliminated, because it has high inorganic constituents content and it was difficult to further process. The second extraction was done at the higher pH ca 12, the solution with the acceptable rate of inorganic constituents and HSL was prepared, which was further refined. Sedimentation of prepared HK solutions was by a natural cooling (ca 16 hours). Then the solution was separated from the sediment and centrifuged for 15 minutes at 5000–9000 revolutions per minute (RCF=2000–7000xg) or the separation was done by the long-term sedimentation (1 month) of HK solution diluted to HS content ca 5 %. In the case of the peat processing, the reaction mixture was filtered after partial cooling (ca 40 °C) through the thin filtration cloth or across the sieve of 5mm mesh and the other day the solution was centrifuged. HS concentration in solutions after the alkaline extraction was in the range 3–10 % (the sample C3H from the coal had the concentration 0.9 %) and the extraction HK efficiency was in the range 80–90 %. Some HS were lost in the sediment at the centrifugation or sedimentation. Yields in refined solutions were in the range 30–80 % depending on the raw material type and on the requirements on the inorganic constituent content reduction in the product. The last step was the HA coagulation from the HK solution by sulphuric acid at pH 1.4–1.6, followed by filtration and rinsing by distilled water to final filtrate pH 2.5. The HS lost in the filtrate at filtration and rinsing was ca 1 %. The filtration cake of HA was in all cases dried in the open air at room temperature. Further HA were prepared from coal, oxyhumolite (X5) and lignite samples, which have low HSL content also after their oxidation by nitric acid in suspension (inspired by results of paper [9]). In terms of the optimization, the best conditions of oxidation were chosen. The 10–15% nitric acid was used in accordance with results mentioned in papers [10, 11]. The weight ratio of acid (100%) and coal was in our case in the range 0.24–0.32. Temperature of the suspension was kept 60 °C. Oxidation was ended by cooling after 2,5 hours. Final pH was 0.6–1.0. The mixture was filtrated and the filtration cake was rinsed by the distilled water. Further treatment of oxidized materials (the rinsed filtration cake) was the same as the origin raw materials were.

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2.3. Methods of Basic Analysis Raw materials and samples (HK and HA) prepared from them were analyzed. The humidity, ash content, organic part (OP), leachable HS (HSL), fulvic acids (FA), carboxylic functional groups (-COOH), total acidity content and inorganic constituents in HS were determined, as described in details elsewhere [2]. The HSL content, the criterion of the oxidation level of the origin material or of the samples oxidized by nitric acid, was not determined in products (HK and HA), because it corresponds there with OP content.

2.4. Organic Elemental Analysis

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Elemental analysis was determined for raw materials and HA prepared from them. It was determined at the CHNO analytic apparatus Flash EA 1112 (Thermo Finnigan) with temperature conductive detector (TCD). Content of S was determined by X-ray fluorescence analyse (RFA) by the PHILIPS PW 1404 spectrometer equipped with UniQuant software [2]. Content of O was calculated as the remainder to 100 %. Contents of single elements were recalculated as water and ash-free (daf).

3. RESULTS The overview of raw materials and prepared samples with the specification of their origin and basic analysis is presented in Table 1. To recognize the influence of each preparation step, analysis of HK which the HA were prepared from, are presented in the same Table. In the case of HK analysis of total ash content and ash without K2O content are calculated from the inorganic constituent’s composition. In the case of raw materials and HA the presented ash content were determined by annealing at 900 °C. The inorganic constituent’s composition is in Tables 2 and 3. The development of the inorganic constituent composition during preparations is evident from presented results. Ash content decreases after the alkaline extraction, subsequent sedimentation and centrifugation of HK suspension, when especially Si (from the majority elements) is removed. This shows that the silicon compounds are not bound on the humate anion. The presence of various forms of SiO2 and kaolinite Al4(OH)8Si4O10 was found in

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raw materials with higher ash content (C3, X2, X3, and L1) by X-ray fluorescence analyses. These crystalline materials can be mechanically removed from the suspension. Al is in some raw materials in other form then kaolinite, as evidenced by the fact that the significant amount of Al rests in refined HK solutions (X1H, X4H) after completed Si removing by centrifugation. Al content fall is evident further after HA coagulation and filtration in consequence of transfer of some Al compounds in the alkaline and acidic environment into. The case of Fe is similar, Fe content fall is visible only at HA. Anyway, relatively high Fe content is evident in HA presumably because of its bind on humate anion [12]. The As content fall is in all cases visible in HA samples, its removing occurs sometimes already after HK centrifugation. Divalent elements (Ca, Zn, Mn) remove after their freeing from the bonds on carboxyl groups. It can be also similar at the part of Fe. Other elements Cr, Cu, Pb are fast bonded on the humate matrix and either alkaline or acidic environment does not influence their bind. It is markedly confirmed in HA (X3 and S) for Pb, where the increase of its concentration occurred. The strength of Pb and Cu on the humate matrix was presented in paper [13]. Elements Co and Ni are bonded a little less strongly. The S content does not changed in prepared samples; it agrees with its bind in organic heterocycles and eventually in –SH groups. Virtually in all cases the increase of carboxyl group content occurs in isolated HA compared with the raw materials (Table 1), this was the aim of the chosen preparation. According to the data of R. H. Faust [14], just carboxyl groups significantly positively influence the HS biological activity. This finding is also confirmed by our results [15]. The carboxyl group content increased probably via oxidation of HS during the aerobic preparation and also by removing the less oxidized material. The carboxyl group content evidently increases in consequence of the oxidation of the coal with bounded phenolic – OH groups. The total acidity increased only in some cases (Table 1). The correlation of the total acidity with preparation methods respectively with the raw material character is not unique. The coal raw materials oxidation by nitric acid is the strong intervention into the inorganic and organic part of the treated materials. The HSL and carboxyl groups content of the raw materials increased significantly (Table 1). The total acidity changed scarcely. The inorganic part removing is more effective in consequence of the insoluble component transfer into the solution; therefore, the content of some inorganic impurities occurs already after filtration and rinsing of the oxidized suspension.

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Table 1. The basic characteristic of raw materials and prepared samples Sample

C1 C2 C2H

C2A

C3 C3H C3A C4 C5

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C5H C5A X1 H1H X1A X2 X2H X2A X3 X3H X3A X4 X4H

Type and origin coal - Družba oxid. coal Družba HK oxid.coal Družba HA oxid.coal Družba coal - Družba HK - coal Družba HA - coal Družba oxh. - Jiří oxid. oxh. Jiří HK- oxid. oxh. Jiří HA - oxid. oxh. Jiří oxh. - Václav HK - oxh. Václav HA - oxh. Václav oxh. - Václav HK - oxh. Václav HA - oxh. Václav oxh. - Vršany HK - oxh. Vršany HA - oxh. Vršany oxh. - Marie HK - oxh.

ash x

OP

HSL

FA

% on the dry basis 18.92 81.08 11.65 15.13 84.87 70.86

0.30 1.59

HSL/ OP

total COOH acidity meq/g HS 14.4 7.64 0.12 83.5 7.37 2.60

29.64/ 0.37

73.83

8.05

1.97

98.03

7.92

3.02

27.88 35.15/ 3.32 1.91

72.12 65.20

4.70 4.95

0.25

98.10

5.72

2.15

42.68 39.57

57.32 60.43

8.63 8.03

1.27 1.73

28.03/ 1.29 4.07

70.77

8.06

95.93

7.05

2.48

6.30 10.45

1.75

9.63

4.02

7.7 9.2

1.64

9.08

4.27

10.30 10.10

1.13

7.96

4.14

7.87 9.30

2.40

12.55 27.99/ 4.38 7.65 30.84 33.72/ 10.7 4.13

87.45 72.57

7.34

8.42 49.28

82.21

0.34

0.46 1.12

2.39

10.2

14.7 81.5

94.0

92.35 69.16 70.12

54.84

1.56

63.13

95.87

51.56 31.29/ 6.12 6.79

48.44 66.68 93.20

8.24 31.62/

91.80 69.42

40.39

84.16

3.44

2.05

83.4

91.7

Humic Acids from Raw Materials of the Czech Republic, Nova Science Publishers, Incorporated, 2010. ProQuest Ebook

Preparation and Elemental Composition

X4A X5 X5H X5A X6 X6H X6A L1 L1H L1A L2 L2H

Copyright © 2010. Nova Science Publishers, Incorporated. All rights reserved.

L2A P1 P1H P1A P2 P2H P2A S SA Fluka x

Marie 2.23 HA - oxh. 3.15 Marie oxh. - Jiří 41.08 HK - oxh. Jiří 31.49/ 4.63 HA - oxh. Jiří 3.69 oxid. oxh. 37.82 Jiří HK - oxid. 28.52/ oxh. Jiří 0.57 HA - oxid. 3.84 oxh. Jiří lignite 16.04 HK - lignite 27.43/ 4.78 HA - lignite 6.37 oxid. lignite 9.94 HK - oxid. 29.05/ lignite 0.50 HA - oxid. 3.13 lignite peat - Branná 23.05 HK - peat 26.87/ Branná 6.99 HA - peat 7.12 Branná peat - Světlík 15.83 HK - peat 27.90/ Světlík 8.02 HA - peat 5.13 Světlík HK36.89/ chernozem 4.13 HA 10.80 chernozem HA - cmrc 14.57 product

96.90 58.92 66.41 96.31 62.18

26.61

0.13

45.2

56.46

1.19

90.8

9

7.52

4.13

7.95 8.22

1.15

7.63 6.69

2.74 2.00

71.89

7.25

96.16

7.43

2.42

7.04 7.56

0.16

8.90 8.77 8.20

2.64 2.67

8.15

3.20

6.18 9.52

0.87

8.10

2.73

5.56 7.54

1.04

7.44

2.49

83.96 63.12 93.63 90.06 71.64

23.30

0.77

27.8

74.03

4.96

82.2

96.87 76.95 73.13

45.19

5.23

58.72

92.88 84.17 77.13

46.86

5.78

94.87 56.69

54.96

89.20

85.86

85.43

n

55.67

4.55 a

9.25

0.89

HK samples - the first value is total ash content, the second value is ash content without K. oxh. = oxyhumolite oxid. = oxidized cmrc product = commercial product

Humic Acids from Raw Materials of the Czech Republic, Nova Science Publishers, Incorporated, 2010. ProQuest Ebook

10

Libuše Madronová, Jaromír Novák, Josef Kozler et al.

Assuming the normal distribution, it was found on the probability level 95%, that oxidized substrates contain more extractable matters (HSL). According to the higher value of variance, it was certified on the lower probability level (90 %), that the -COOH content of substrates increased owing to the oxidation. HSL content increased after the oxidation on average 3,6times; mostly in the case of coal C1 (6.1times), the least at oxyhumolite X5 (2.2times). The average –COOH group content increased by the substrate’s oxidation 3.3times, mostly at coal C1 (almost 22times); the least at oxyhumolite X5 and coal C5 (1.7times and 1.4times, respectively). Raw materials from the mine Jiří are contaminated especially by arsenic and zinc, which were brought to the deposit by underground and surface water from the ore bed in Krušné mountains. According to this contamination, products from this material would not be applicable in biotechnology. They were studied with the aim to compare the preparation and refining methods and structural parameters with other raw materials.

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Table 2. Inorganic constituents in HS - majority elements [% on dry basis] Sample Type and origin coal - Družba C1 oxid. coal C2 Družba C2H HK oxid.coal,Družba C2A HA -oxid.coal Družba coal - Družba C3 C3H HK - coal Družba C3A HA - coal Družba oxh. - Jiří C4 oxid. oxh. - Jiří C5 C5H HK- oxid. oxh. Jiří C5A HA - oxid. oxh. Jiří oxh. - Václav X1 H1H HK - oxh. Václav X1A HA - oxh. Václav

Na Mg Al Si S Cl K Ca Ti Fe 0.56 0.15 3.29 9.93 0.79