Reducing Sugar in Calcium Lignosulfonates
Calcium lignosulfonate from the sulfite pulping of wood waste, a saccharide which contains a certain amount of chemicals, mainly pentose and hexose, they are more or less affect the performance of the concrete, on to wood as raw material sulfite pulping liquor in a source of sugar, the nature of the so-called “high-sugar” and “low sugar” instructions for the user to select calcium lignosulfonate reference. Calcium lignosulfonate from the sulfite pulping of wood waste, the data indicate that the sugar is present in the form of lignin – polysaccharide complexes (lignin-carbohydrate Complex, referred to as LCC), they are coupled to a number of ways, these coupled with the lignin sugars, including: xylose, arabinose, mannose, glucose, galactose, uronic acid. The sugars collectively referred to as the five-carbon sugar and six-carbon sugar, because some of the sugar with the reduction of so referred to as “reducing sugar, lignin – glycan complex following connection mode.
Bonus hydroxy-alpha – A-ether bond binding sugar to the binding for the alpha-ether bond and methylene quinone. The anisole-acid-sensitive keys, the weak acid or dioxane – water (1:1) solution heated to 180 ° C, as shown in Figure 1, is cut off.
B alpha-ester bonded to the carboxyl group of glucuronic acid addition to a methylene quinone to form an ester bond, as shown in Fig.2, the addition reaction of calcium lignosulfonate methylene quinone group, a carboxyl group than the saccharide is easy Broadleaf there may exist such a key, this key as shown in Fig 2 to alkali sensitive, mild alkaline treatment (1N sodium hydroxide at room temperature) is also very easily hydrolyzed.
C-CO-and-CC-bond radical condensation of the-CO-and-CC-key, as shown in Fig.3, to produce such an ether bond is very easy and hydrolysis resistance than the A and B keys strong, and can not be glycosides enzymatic degradation. May be a resistance to acidic hydrolysis, alkaline decomposition and hydrolysis strong key exists in the timber.
D formed in the the phenylpropanoid side chains gamma-bit and beta-bit glycoside bond This combination has proved difficult to hydrolysis
Reduction in calcium lignosulfonate comprises two parts, namely reducing sugar + slow combination of sulfur dioxide, used to refer to the analysis of lignin sulfonate reducing sugar reducing substances. Now use lignosulfonate enterprise, analysis of “reducing sugar” There are two ways, one is reducing sugar content in test methods GB 8077-87 “uniformity of concrete admixture test methods”, the other is ZBG-52001 “the dispersant M-9 in the determination of total reducing content, the former for the construction industry, the latter for the dye industry, as far as we know, domestic production oflignin sulfonate enterprises, the majority of , the ZBG-52001 “the dispersant M-9 in total reducing content determination.