Determination of the degree of sulfonation of sodium lignosulfonate

کد مقاله : 1108-ICOC

نویسندگان

هانیه سیفی *، عباس دادخواه تهرانی دانشگاه لرستان

چکیده مقاله

One of the valuable derivatives of lignin is lignin sulfates, which today constitute 90% of the commercial lignin market. The degree of sulfonation (DS) is one of the most important structural parameters that affects physical and chemical properties, including water solubility, dispersion efficiency, and complexation ability. The present study aimed to develop and validate an experimental, low-cost, and accessible method for determining the degree of sulfonation of sodium lignosulfonate by precipitation with cetyltrimethylammonium bromide (CTAB) under optimal conditions (pH = 1.5, ambient temperature, sample volume to CTAB ratio of 1.1 ml). To validate the developed method, the degree of sulfonation (DS) of sodium lignosulfonate sample was also measured using the CHNS method. In addition, the sulfur percentage calculated from both methods was compared. To confirm the structural changes of sodium lignosulfonate using cetyltrimethylammonium bromide (CTAB), FTIR, XRD, and TGA analyses were used. The results proved that under optimal conditions, the calculated degree of sulfonation was very accurate and with the lowest error (0.368) compared to the standard CHNS method, which indicates the accuracy of the precipitation method. Furthermore, factors such as the effect of pH and temperature for this method showed that increasing acidity (decreasing pH) facilitated optimization, while temperature changes had no significant effect. Considering the simplicity, speed, low cost and no need for complex equipment, the presented method is a suitable option for determining the degree of sulfonation (DS) of sodium lignosulfonate in applied and industrial research.

کلیدواژه ها

Lignin , Sodium lignosulfonate , Cetyltrimethylammonium bromide (CTAB) , Determination of the degree of sulfonation ( DS) , Sedimentation method

وضعیت: پذیرفته شده