Dataset underlying the publication: All-lignin polyelectrolyte multilayers as renewable and biodegradable nanofiltration membranes

The data includes the following datasets:<br>dn_dc_for_Q_factor_determination: refractive indexes of lignin solutions measured at different concentrations (g/L) of lignin at different wavelengths (nm) of incoming light. The linear fit function in excel was used to determine the dn/dc from the presented data. The fit data can be found in the SI of the article.<br>Filtration: Contains experimental results of crossflow filtration measurements for pure water permeability, 90% molecular weight cut off (MWCO) data based on polyethylene glycol (PEG) retentions (100-10000 g/mol) as measured by Gell permeation chromatography (GPC), and MgSO4 retention data. Measured quantities are: active fibre length (m), average [inlet and outlet] pressure (bar), permeate mass (g) [filled beaker-empty beaker], permeation time (s), feed and permeate conductivity (microS/cm).<br>Fourier transform infrared spectroscopy data (FTIR): From the 3 different cationic lignin batches used in the article, the lignosulfonates and the unmodified Kraft lignin. batch number 1 was used for figure 2 in the article; batch number 2 was used for the salt stability, pH stability and biodegradability experiments (Figure 4, 5 and 6 of the main article and figure S4, S6, S7 and S9 of the SI); batch number 3 was used for the reflectometry and layer growth experiments at different NaCl concentrations (figure 3 in the article). the wavelength (cm-1) and signal intensity (a.u.) are presented.<br>H-NMR: 1H-NMR data of the different cationic lignin batches, lignosulfonate and unmodified Kraft lignin. The chemical shift (ppm) and signal intensity (a.u.) are presented<br>P-NMR: 31P-NMR data of the unmodified Kraft lignin and lignosulfonate. To calculate the OH content of the lignin from this data the MestreNova software was used. The chemical shift (ppm) and signal intensity (a.u.) are presented<br>SEM: FESEM images of the bare support and the support coated with 9.5 or 10.0 bilayers of lignin<br>Reflectometry: Reflectometry data for the lignins coated from 5, 50 and 500 mM NaCl solutions onto a silicon waver. The Q factors as determined from the dn/dc data and the professor Huygens software are presented together with the signal (S) base signal (So) and calculated adsorption (Ads) in mg/m2.<br>

本数据集包含以下子数据集：
dn_dc_for_Q_factor_determination：用于Q因子（Q-factor）测定的dn/dc数据集：不同入射光波长（nm）下，不同木质素浓度（g/L）的木质素溶液折射率。本研究采用Excel内置的线性拟合函数对所呈现数据进行拟合，以计算得到dn/dc值。拟合所得数据可参见本文的补充材料（Supporting Information, SI）。
Filtration：错流过滤实验数据集：包含错流过滤测量的多项实验结果，具体包括纯水渗透率、基于聚乙二醇（polyethylene glycol, PEG）截留率的90%截留分子量（molecular weight cut off, MWCO）数据（PEG分子量范围为100~10000 g/mol，通过凝胶渗透色谱（gel permeation chromatography, GPC）测定），以及硫酸镁（MgSO₄）截留率数据。本次实验测定的参数包括：有效纤维长度（m）、平均进出口压力（bar）、渗透物质量（g，计算方式为装满烧杯的质量减去空烧杯的质量）、渗透时间（s）、进料液与渗透液电导率（microS/cm）。
Fourier transform infrared spectroscopy data (FTIR)：傅里叶变换红外光谱（Fourier transform infrared spectroscopy, FTIR）数据集：涵盖本文研究所用的3批不同阳离子木质素、木质素磺酸盐以及未改性牛皮木质素的光谱数据。其中，批次1用于本文图2；批次2用于盐稳定性、pH稳定性与生物降解性实验（对应正文图4、5、6，以及补充材料图S4、S6、S7、S9）；批次3用于不同氯化钠（NaCl）浓度下的反射率测试与膜层生长实验（对应本文图3）。数据包含波长（cm⁻¹）与信号强度（a.u.，任意单位）。
H-NMR：氢核磁共振（¹H-NMR）数据集：包含不同批次阳离子木质素、木质素磺酸盐以及未改性牛皮木质素的¹H-NMR数据。数据呈现化学位移（ppm）与信号强度（a.u.，任意单位）。
P-NMR：磷核磁共振（³¹P-NMR）数据集：包含未改性牛皮木质素与木质素磺酸盐的³¹P-NMR数据。本研究采用MestreNova软件对该数据进行处理，以计算木质素的羟基含量。数据呈现化学位移（ppm）与信号强度（a.u.，任意单位）。
SEM：场发射扫描电子显微镜（field emission scanning electron microscopy, FESEM）图像数据集：包含裸支撑层以及涂覆9.5或10.0层木质素双分子层的支撑层的FESEM图像。
Reflectometry：反射率测量数据集：包含从5 mM、50 mM与500 mM氯化钠溶液中涂覆至硅片（silicon wafer）表面的木质素的反射率数据。本研究结合dn/dc测定结果与Huygens软件得到的Q因子，以及信号强度（S）、基础信号（S₀）与计算得到的吸附量（Ads，单位mg/m²）一并呈现。