Wastewater from the tofu industry contains many pollutants that are very harmful to the environment, significantly endangering aquatic life and producing a pungent odor. This study aims to prepare a polyvinylidene fluoride (PVDF) membrane with the additive polyvinylpyrrolidone (PVP), and utilize it to treat tofu wastewater in the ultrafiltration (UF) process. Flat sheet membranes were prepared using PVDF that was dissolved in N,N-dimethylacetamide (DMAc) and then combined with the additive material of PVP at the varying compositions of 14.9/0.1, 14.85/0.15, and 14.8/0.2 g of PVDF/gram of PVP. The addition of PVP was proposed to improve the properties of the membranes. Characterization by scanning electron microscope (SEM), water contact angle, and Fourier transform infrared spectroscopy (FTIR) were performed on the PVDF/PVP membrane flat sheet in order to understand and compare changes in the physical and chemical properties that occurred in the membrane. Prior to the UF process, the tofu wastewater was treated by a coagulation–flocculation process through a jar tester using poly aluminum chloride (PAC) as a coagulant. Based on the membrane characterization, the addition of PVP improved the physical and chemical properties of membranes. The pore size of the membrane becomes larger, which could increase permeability as well as the flux value. The TSS and turbidity of the water produced in the UF process decreased with an increase in feed pressure due to a greater driving force generated to facilitate the penetration of the suspended solids. The UF results showed that the effect of PVP on water flux was greatest for the 14.85/0.15 PVDF/PVP membrane for both pure and wastewater. In addition, the highest percentage of rejection for TSS and turbidity were observed in the 14.9/0.1 PVDF/PVP membrane and rejection for TDS was indicated in the 14.8/0.2 PVDF/PVP membrane. Meanwhile, the resulting pH decreased slightly across all samples as feed pressure increased.

Semen merupakan bahan dasar utama konstruksi bangunan, sehingga menjadikan semen sebagai komoditi yang strategis. Semen PCC (Portland Composite Cement) merupakan jenis semen varian baru yang mempunyai karakteristik mirip dengan semen Portland, tetapi semen jenis ini mempunyai kualitas yang lebih baik, ramah lingkungan dan mempunyai harga yang lebih ekonomis. Penambahan limestone sebagai aditif berfungsi meningkatkan kuat tekan pada semen. Tujuan penelitian ini adalah mengetahui pengaruh penambahan limestone dengan berbagai variasi terhadap kuat tekan dan menentukan massa limestone yang dapat memberikan kuat tekan maksimum pada semen Portland komposit. Pembuatan semen Portland komposit dilakukan dengan penambahan limestone sebagai aditif. Variasi limestone yang ditambakan adalah 0, 5, 10, 15, 20 dan 25%. Pengaruh penambahan limestone dapat diketahui dari hasil uji kehalusan, uji residu, uji komposisi kimia semen dan uji kuat tekan semen. Hasil penelitian menunjukan bahwa semakin besar persentase pemakaian limestone di dalam blended cement maka nilai residu dan nilai kehalusan akan semakin besar namun nilai kuat tekan akan semakin rendah. Kuat tekan semen yang tertinggi yaitu nilai kuat tekan pada umur 2 hari. Komposisi terbaik aditif limestone di dalam blended cement adalah 77% klinker, 15% lime stone, 3% gypsum dan 5% blast furnace slag

Selecting a proper material is the first key step for determining suitable membrane application. Hence, the comparison of membrane properties is urgently required to be conducted. This work aimed to compare two common materials of polymer flat sheet membranes, i.e poly(vinylidene) fluoride (PVDF) and polysulfone (PSf), from preparation to characterization. Phase inversion method was applied for both materials using different solvent. PVDF was dissolved in N, N, dimethyl acetamide (DMAc) whereas PSf was dissolved in N-methyl pyrrolidone (NMP) with the same composition ratio of polymer and solvent. The properties of membranes were investigated by FTIR, FE-SEM, water contact angle, and Universal pull machine. FE-SEM result indicates that PSf membrane has larger pores than PVDF membrane. Meanwhile, water contact angle analysis describes that PVDF membrane is more hydrophilic than PSf membrane.

Para pemuda bergerak memulai bisnis melalui program kewirausahaan yang diprakarsai oleh berbagai institusi sehingga meningkatkan kesadaran generasi milenial untuk berwirausaha bahkan sebagian telah memulai bisnis permulaan (startup business). Tantangan besar adalah bagaimana menjaga semangat bisnis di kalangan milenial tetap menyala dan menyiapkan mahasiswa pengusaha dalam menghadapi berbagai tantangan dalam menjalankan bisnis mereka agar bertahan dan sukses. Program Pengembangan Kewirausahaan (PPK) di Pusat Inkubator Bisnis dan Kewirausahaan (PIBK) Universitas Muhammadiyah Jakarta (UMJ) dapat menjawab tantangan besar tersebut. PPK PIBK UMJ mengumpulkan proposal bisnis mahasiswa, menyeleksi proposal untuk didanai (selanjutnya disebut tenant), memberikan pembekalan kepada tenant (strategi pemasaran, laporan keuangan, pola fikir wirausaha), memantau omset dan mengevaluasi produktivitas tenant setiap tiga bulan sekali, dari Februari 2017 sampai Januari 2018. Sumber pendanaan PPK PIBK UMJ adalah dari Kementerian Riset, teknologi dan Pendidikan Tinggi. Terdapat 85 proposal bisis dari mahasiswa UMJ. 20 proposal terpilih sebagai tenant di PPK PIBK UMJ. Dari 20 tenant pada akhir tahun 2018, 5 tenant memperoleh omset diatas lima juta rupiah perbulan dengan produktivitas yang berkesinambungan. Lima tenant ini disebut usaha rintisan mandiri (independent startup). Kesimpulan, PPK PIBK UMJ pada tahun 2018 telah melahirkan lima usaha rintisan mandiri. Katakunci: Kewirausahaan, usaha rintisan, Mahasiswa Pengusaha, inkubator bisnis, tenant, usaha rintisan mandiri.

Batik is a cultural heritage which was handed down to her craftsmen in Indonesia, even now it is recognized by UNESCO as one of the world heritages. However, the batik industry is also known as an industry that discharges a lot of wastewater so that the processing of batik waste becomes very important to prevent surface water pollution from batik wastewater. Therefore, this study aims to examine the performance of polypropylene (PP) fibers-based membrane module in wastewater treatment from the batik industry. The batik wastewater was prior treated through a combination of ozonation (O3) and flocculation, and then ultra-filtered by a PP membrane module at various trans membrane pressures (TMP). Conductivity, total suspended solids (TSS), chemical oxygen demand (COD) and color (Pt/Co) were the observed variables to examine the performance of the batik wastewater treatment process. The experimental results show that TSS, COD and Pt/Co can be reduced by about 99.8%, 24% and 57%, respectively. Meanwhile, the permeate fluxes from the membrane module were 141.3, 182.0, 243.9, 264.7 and 290.88 L.m−2.h−1 at TMP of 3, 5, 7, 9 and 11 bars, respectively.