Modified Sodium Lignosulfonate And Its Application In Scrub Hand Sanitizer For Industrial Oil Decontamination

Lignosulfonate（LS）is an abundant and renewable source of organic carbon found in nature,mainly produced as a byproduct of pulp manufacturing processes.It can be used as a dispersant to stably disperse solid or liquid in the system medium.However,since LS has low surface activity,it is not suitable for direct use as a dispersant.Therefore,it is advisable to incorporate hydrophilic polyethers and hydrophobic long chain alkyl groups into the molecular structure of lignosulfonate（LS）to enhance its dispersion performance and improve surface activity.This modification is crucial in expanding the scope of applications for lignin-based dispersants.In this study,graft copolymerization and electrostatic self-assembly techniques were employed to modify sodium lignosulfonate（SL）,and a new dispersant,BAC-SL-HPEG,which is anionic cationic polymer dispersant based on lignin,was synthesized.This dispersant was used in the research of scrub hand sanitizer for industrial oil decontamination.Key findings of the study are summarized below:1.Preparation of BAC-SL-HPEG:In this paper,sodium lignosulfonate graft copolymer（SL-HPEG）was synthesized by aqueous polymerization using methylallyl polyoxyethylene ether（HPEG）as monomer and potassium persulfate（K₂S₂O₈）as initiator.The Box-Behnken response surface design was used to optimize the grafting process parameters.The results showed that the optimal grafting rate was achieved with a monomer dosage of 63.965%,an initiator dosage of 4.734%,a reaction temperature of 80℃,and a reaction time of 4.0 h.The structure of SL-HPEG was analyzed using various techniques,including FT-IR,¹H NMR,contact angle measurements,and scanning electron microscopy（SEM）.The results showed that the hydrophilicity of the SL-HPEG was enhanced,and the content of phenolic hydroxyl group in the SL structure decreased after HPEG was inserted,and the surface structure changed from smooth sphere to rough sheet,that is,HPEG was successfully grafted onto the SL molecular structure.Simultaneously,BAC-SL-HPEG was synthesized by electrostatic self-assembly by incorporating dodecyl dimethyl benzyl ammonium chloride（BAC）into the side chain of the SL-HPEG molecular structure.When analyzing the Zeta potential and particle size of SL-HPEG combined with BAC in aqueous solution,it was found that an isoelectric point was reached when the mass ratio of BAC to SL-HPEG was 1.25.Consequently,various BAC-SL-HPEGs with different mass ratios of anions and cations were subsequently prepared.The structure of the electrostatic self-assembly product was characterized by FT-IR,¹H NMR and contact angle.The results showed that BAC was successfully incorporated into SL-HPEG’s molecular structure,which led to an increase in hydrophobicity and improved particle dispersion through electrostatic self-assembly.The preparation of BAC-SL-HPEG was successfully achieved.2.Application of BAC-SL-HPEG:in the research of scrub hand sanitizer for industrial oil decontamination.By exploring the influence of carbomer type,carbomer mass fraction concentration,and p H value of the solution system on the viscosity of the system,as well as the skin sensitivity questionnaire survey of products made of different carbomer types,a comprehensive analysis was carried out,selecting carbomer941 compound triethanolamine as the main system type of the product.The dosage of carbomer 941 was determined to be 0.50%,the dosage of triethanolamine to be 0.25%,and the viscosity of the product could reach 79000 m Pa.s.Alkylphenol polyoxyethylene ether（OP-10）,fatty alcohol polyoxyethylene ether（AEO-9）,isocetyl alcohol polyoxyethylene ether（1309）,white oil,glycerin were selected as the emulsifying system of the product.With decontamination capacity as the index,the additional amount of each raw material in the emulsification system was determined by orthogonal experiment:OP-10 9.00%,AEO-9 9.50%,1309 5.00%,white oil 5.00%,glycerol 2.50%.Based on the R range of each factor,it is concluded that the primary and secondary influences of the five factors on the decontamination index are:OP-10>1309>AEO-9>white oil>glycerin.As for the dispersion performance of the particles in the product,the optical microscope imaging and dispersion stability of SL,SL-HPEG and BAC-SL-HPEG dispersion systems were analyzed.The results showed that the BAC-SL-HPEG dispersant obtained by graft copolymerization and electrostatic self-assembly modification had good particle dispersion ability.BAC-SL-HPEG was used as the main dispersing agent in scrub hand sanitizer for industrial oil decontamination,and the relationship between the amount of dispersing agent and the stability of the product was explored by changing the proportion of dispersing agent in the product.The results show that when the dispersant is added above 3.00%,the product exhibits good stability at both high and low temperatures.Based on the economic value and visual sensory effect of the product,the additive amount of BAC-SL-HPEG dispersant was determined to be 3.00%.Finally,add 1-2 drops of fragrance,a small amount of pigment,and 0.07%kasone fungicide to adjust the scent,color,and corrosion of the product.Afterwards,tests were carried out to evaluate the hygiene,health and other indicators of the product,and the results showed that all the indicators of the product were in line with the"Cosmetic Safety Technical Specification（2015edition）"and GB/T 13173-2008,GB/T 34855-2017 national standards,which indicated the successful research of scrub hand sanitizer for industrial oil decontamination.In this paper,the"waste"SL from a wide range of sources and low price is modified back into the daily scrubber,realizing the successful transformation of SL in the actual product and expanding the application of SL in the daily scrubber.Due to the limited availability of resources,SL related research can bring environmental benefits,while studying the use of hand sanitizer for industrial oil decontamination can yield economic benefits on the market.